User Requirements Document

Transcription

1 2.rev.2 22/02/ User Requirements Dcument Milestne User Requirements Dcument Milestne 1 Authrs Martin Herld, WUR Annemarie van Grenestijn, WUR Lammert Kistra, WUR Vasileis Kalgiru, ESA/ESRIN Olivier Arin, ESA/ESRIN Distributin ESA UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

2 2.rev.2 22/02/ Summary Within the ESA Climate Change Initiative (CCI), a glbal mnitring prgram driven by GCOS requirements is in develpment t prvide lng-term satellite-based prducts which can serve the climate mdeling and climate user cmmunity. Land Cver has been selected as ne f 11 ECVs which will be elabrated during the first phase f CCI ( ). In the first stage f the Land Cver CCI prject, a user requirements analysis has been cnducted t derive the specificatins fr a new glbal land cver prduct t address the needs f key-users frm the climate mdeling cmmunity. This user assessment is building upn the general guidance and requirements frm GCOS an its related panel activities and prvides the next step t further derive mre detailed characteristics and fundatins t bserve Land Cver as Essential Climate Variable (ECV). As part f the requirements analysis, an user cnsultatin mechanism was set-up t actively invlve different climate mdeling grups by setting ut surveys t different type f users: 1) a grup f keyusers, mst f them als participating in CMUG, 2) assciated climate users wh are invlved and leading the develpment f key climate relevant mdels and applicatin, and 3) the brad land cver data user cmmunity reflected in the scientific literature and represented by users f the ESA GlbCver prduct. The surveys fcused n three majr ways land cver bservatins are used in climate mdels: 1. As prxy fr several land surface parameters assigned based n Plant Functinal Types (PFTs); 2. As prxy fr (tracking) human activities, i.e. land use affecting land cver; 3. As datasets fr validatin f mdel utcmes (i.e. time series) r t study feedback effects. The evlutin f requirements fr these aspects frm current mdels t future new mdeling appraches was specifically taken int accunt. Next t the surveys, requirements frm the GCOS Implementatin Plan 2004 and 2010 and assciated strategic earth bservatin dcuments fr land cver (GTOS, IGOL, IGCO and CMUG) were cnsidered and integrated. Finally, a detailed literature review was carried ut with special attentin t innvative cncepts and appraches t better reflect land dynamics in the next generatin climate mdels. The utcme f the user requirements assessment shws that althugh the range f requirements cming frm the climate mdeling cmmunity is brad, there is a gd match amng the requirements cming frm different user grups and the brader requirements derived frm GCOS, CMUG and ther relevant internatinal panels. The findings highlight that: There is need fr bth stable land cver data and a dynamic cmpnent in frm f time-series and changes in land cver; Cnsistency amng the different mdel parameters is ften mre imprtant than accuracy f individual datasets, and it is imprtant t understand the relatinship between land cver classifiers with the parameters and the relative imprtance f different land cver classes; Prviding infrmatin n natural versus anthrpgenic vegetatin (disturbed fractin) and track human activities and define histry f disturbance is f increasing relevance; in particular fr land use affecting land cver with mst detail needed fr fcus areas with large anthrpgenic effects; Land cver prducts shuld prvide flexibility t serve different scales and purpses bth in terms f spatial and tempral reslutin; UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

3 2.rev.2 22/02/ The relative imprtance f different class accuracies varies significantly depending n which surface parameter is estimated and the need fr stability in accuracy shuld be reflected in implementing a multi-date accuracy assessment; Future requirements fr tempral reslutin refer t intra-annual and mnthly dynamics f land cver including als remte sensing time series signals; Mre than 90% f the general land cver users find the UN Land Cver Classificatin System a suitable apprach fr thematic characterizatin; and this apprach is als quite cmpatible with the PFT cncept f many mdels; Quality f land cver prducts need t be transparent by using quality flags and cntrls, and including infrmatin n the prbability fr the land cver class r anticipated secnd class r even the prbability distributin functin fr each class (cming frm the classificatin algrithm). As a next step within the Land Cver CCI prject, the utcme f this user requirements assessment will be used as input fr the prduct specificatin f the next generatin Glbal Land Cver dataset which will be develped within this prject. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

4 2.rev.2 22/02/ Table f recrded changes Issue Recrd Sheet ISSUE DATE REASON /11/2010 Initial versin /11/2010 Updated versin accrding t RIDs frm prgress meeting /01/2011 Updates versin accrding t RIDs (related t versin 1.0) frm ESA /02/2011 Updates versin accrding t RIDs (related t versin 2.1) frm ESA and t the cmments received at PM3 Detailed Change Recrd Sheet ISSUE RID Sectin Change 2.0 URD/1 All Several editrial changes as requested. URD/ URD/17 Sectin 4.10 Additinal sectin has been added which presents the summary f requirements fr Land Cver ECV accrding t the ESA template fr rganizing ECV user requirements. 2.0 URD/18 Appendix D The respndents t the assciated user survey have been indicated with an asterix in Appendix D. 2.0 URD/19 Sectin 4.5 The discussin n C3/C4 differentatin has been expanded: pprtunities fr EO and ther data surces have been identified and backgrund references have been added. 2.1 Frm PM2 Sectin 4.7 Accrding t feedback in RID frm ESA we have cntacted the key-users n their requirements fr metadata and quality cntrl indicatrs. The utcme has been added t sectin Frm PM2 Sectin Final feedback frm assciated users n Land Cver ECV summary dcument has been added t sectin URD/20 Sectin 4.10 Statement f Appendix has been remved. In additin, infrmatin abut metadata and prjectin has been added. 2.2 URD/21 Sectins 4.7 and 4.10 As has been discussed in sectin 4.7 users mainly articulated in meta data n the quality f the land cver dataset. Sectin 4.7 has been updated with sme mre requirements, als taking int accunt the recent CMUG reprt. Subsequently, sectin 4.10 has been updated as well in harmnizatin with sectin URD/22 Sectin 4.5 The discussins n C3/C4 has been expanded in sectin 4.5 Recent reference n use f MERIS MTCI fr identificatin f C3-C4 grasslands has been added and cnsequences fr generalizatin added. 2.2 Frm PM3 Sectin 4.5 The mentin f the imprtance f irrigated rice areas has been added in sectin 4.5. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

5 2.rev.2 22/02/ Table f cntent SUMMARY... 2 TABLE OF RECORDED CHANGES... 4 TABLE OF CONTENT... 5 LIST OF FIGURES... 7 LIST OF TABLES... 9 LIST OF ACRONYMS BACKGROUND AND SCOPE Need fr cmmunity and user interactin t specify requirements fr ECV mnitring Land cver and climate mdeling User engagement mechanism Types f users representing the climate mdel user grups METHODOLOGY Brad assessment f user requirements Key user requirements cnsultatin Next generatin mdel requirements RESULTS OF USER CONSULTATIONS Analysis f GCOS and ther earth bservatin strategic dcuments GCOS implementatin plan and accuracy needs GCOS principles GTOS requirements IGOL requirements IGCO requirements Results f brader user assessment Assessment f Climate mdelling cmmunity requirements CMUG requirements Results f key user survey Analysis f mdel parameters versus land cver Results f assciated user survey...48 UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

6 2.rev.2 22/02/ Scientific literature review SYNTHESIS AND RECOMMENDATIONS Need fr land cver in climate mdels User requirement 1: Accuracy User requirement 2: Spatial detail User requirement 3: Tempral reslutin User requirement 4: Land cver categrizatin User requirement 5: Land cver change User requirement 6: Metadata, quality cntrl, frmat and prjectin GCOS principles Brader guidance versus detailed user requirements Summary Land Cver ECV User Requirements REFERENCES APPENDIX A: BROAD USER SURVEY APPENDIX B: ASSOCIATE USER SURVEY APPENDIX C: KEY USER SURVEY APPENDIX D: OVERVIEW OF GROUPS CONTACTED AS ASSOCIATE USERS UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

7 2.rev.2 22/02/ List f figures FIGURE 1: ROLE OF LAND IN LONG-RUN (E.G., CENTENNIAL) CLIMATE MODELING (ROSE ET AL. 2008) FIGURE 2: THE MULTI-SCALE AND MULTI-PURPOSE NATURE OF CLIMATE AND CARBON MODELS, I.E. SOIL, ECOSYSTEM, DYNAMIC GLOBAL VEGETATION MODEL (DGVMS), AND GENERAL CIRCULATION MODELS (GCMS): SCALES OF PREDICTION AND PROCESS RESOLUTION. SHOWING THAT THE LEVEL OF DETAIL IN PROCESS RESOLUTION GENERALLY DIMINISHES AS THE PREDICTIVE SCALE (SPATIAL AND TEMPORAL) OF THE MODEL INCREASES (FROM OSTLE ET AL., 2009) FIGURE 3: CONCEPT OF USER REQUIREMENT ASSESSMENT AS PART OF THE OVERALL BREAKDOWN STRUCTURE OF LAND COVER CCI PROJECT FIGURE 4: OVERVIEW OF THE USER REQUIREMENT ASSESSMENT METHODOLOGY FOR CONSULTATION OF THE CLIMATE MODELING COMMUNITY FIGURE 5: GCOS PRODUCT FRAMEWORK CONSIDERING POTENTIAL SPATIAL RESOLUTIONS REQUIRED BY MODELERS AND KEY ASSOCIATED ISSUES THAT NEED TO BE CONSIDERED IN THE ECV DEVELOPMENT WITH RESPECT TO THE CLIMATE MODELING NEEDS FIGURE 6: CONCEPT OF LINKING AND CHARACTERIZING LAND COVER MAPPING CATEGORIES THROUGH COMMON CLASSIFIERS, THE DEFINITION OF GENERIC CLASSES AND THE APPLICATION OF A CARTOGRAPHIC STANDARD (ADOPTED FROM (HEROLD ET AL. 2009)) FIGURE 7: GLOBAL DISPERSION (PER CONTINENT) OF THE USERS THAT COMPLETED THE BROAD USER SURVEY FIGURE 8: TYPE OF EMPLOYING INSTITUTION OF THE RESPONDENTS FIGURE 9: PREFERENCE FOR SPATIAL RESOLUTION OF LAND COVER DATA PER APPLICATION TYPE FIGURE 10: UPDATE FREQUENCY REQUIRED FOR LAND COVER PRODUCTS PER APPLICATION TYPE FIGURE 11: IMPORTANCE OF LAND COVER CLASSES FOR THE RESPONDENTS APPLICATION FIELD FIGURE 12: LAND CHANGE DYNAMICS IN WHICH BROAD USERS ARE MOST INTERESTED FIGURE 13: TIME FRAME OF THE LAND COVER PRODUCTS THAT ARE USED OR HAVE BEEN USED BY THE KEY-USERS FIGURE 14: SPATIAL RESOLUTION CURRENTLY USED, REQUIRED TO IMPROVE CURRENT MODELS WITH, AND REQUIRED IN NEW MODELING APPROACHES FOR: (LEFT) GENERAL MODELING PRACTICES, (MIDDLE) PARAMETER ESTIMATION, (RIGHT) LAND COVER AND LAND USE CHANGE DETECTION FIGURE 15: TEMPORAL RESOLUTION CURRENTLY USED, REQUIRED TO IMPROVE CURRENT MODELS WITH, AND REQUIRED IN NEW MODELING APPROACHES FOR: (LEFT) GENERAL MODELING PRACTICES, (MIDDLE) PARAMETER ESTIMATION, (RIGHT) LAND COVER AND LAND USE CHANGE DETECTION FIGURE 16: RELATIVE IMPORTANCE ARE DISPLAYED ON WHICH PFTS ARE USED FOR LAND COVER CLASSIFICATION (ACCORDING LCCS, DI GREGORIO, 2005), AND WHICH PFT CLASSES NEED TO BE INCORPORATED AND EXTENDED IN FUTURE MODELING APPROACHES FIGURE 17: HISTOGRAM OF SIMILARITY VALUES (IN PERCENT, X-AXIS) REPRESENTING THE RELATIVE DIFFERENCE IN VALUES AMONG 2 LAND COVER CLASSES FOR FOUR LAND SURFACE PARAMETERS. NOTE: THE SCALE OF Y- SCALE VARY FOR DIFFERENT DIAGRAMS FIGURE 18: EARTH SYSTEM OR CLIMATE MODELING FOCUS OF RESPONDENTS TO ASSOCIATE USER SURVEY FIGURE 19: LAND COVER PRODUCTS USED IN ASSOCIATE CLIMATE MODELING COMMUNITY FIGURE 20: IDENTIFIED PROBLEMS WHEN USING AVAILABLE LAND COVER DATA SETS FOR CLIMATE MODELING APPLICATIONS FIGURE 21: SPATIAL RESOLUTION REQUIREMENTS FOR CURRENT CLIMATE MODEL APPLICATION AND EXPECTED IN UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

8 2.rev.2 22/02/ YEARS FIGURE 22: TEMPORAL RESOLUTION REQUIREMENTS FOR CURRENT CLIMATE MODEL APPLICATION AND EXPECTED IN 5 YEARS FIGURE 23: MOST IMPORTANT LAND COVER CLASSES FOR CURRENT CLIMATE MODEL APPLICATION AND EXPECTED IN 5 YEARS FIGURE 24: MOST RELEVANT HUMAN ACTIVITIES/DISTURBANCES OR DYNAMICS FOR CURRENT CLIMATE MODEL APPLICATION AND EXPECTED IN 5 YEARS FIGURE 25: LAND SURFACE PARAMETERS USED IN CLIMATE MODELS WHICH ARE ESTIMATED FROM THE LAND COVER DATA FIGURE 26: OUTPUT PARAMETERS OF CLIMATE MODELS WHICH ARE OR WILL BE VALIDATED USING LAND COVER DATA FIGURE 27: CONCEPT OF USER COMMUNITIES AND ACTIVITIES TO ASSESS LAND COVER REQUIREMENTS OF GENERAL LAND COVER USER COMMUNITY AND CLIMATE MODELING COMMUNITY FIGURE 28: SYNTHESIS FOR SPATIAL RESOLUTION MEDIAN REQUIREMENTS (NOTE Y-AXIS IN LOG-SCALE) FROM BROAD LAND COVER DATA USER COMMUNITY AND KEY AND ASSOCIATE USERS FROM CLIMATE MODELING COMMUNITY FIGURE 29: SYNTHESIS FOR SPATIAL RESOLUTION MINIMUM REQUIREMENTS (NOTE Y-AXIS IN LOG-SCALE) FROM BROAD LAND COVER DATA USER COMMUNITY AND KEY AND ASSOCIATE USERS FROM CLIMATE MODELING COMMUNITY FIGURE 30: SYNTHESIS FOR TEMPORAL RESOLUTION MEDIAN REQUIREMENTS FROM BROAD LAND COVER DATA USER COMMUNITY AND KEY AND ASSOCIATE USERS FROM CLIMATE MODELING COMMUNITY FIGURE 31: SYNTHESIS FOR TEMPORAL RESOLUTION MINIMUM REQUIREMENTS FROM BROAD LAND COVER DATA USER COMMUNITY AND KEY AND ASSOCIATE USERS FROM CLIMATE MODELING COMMUNITY FIGURE 32: THEMATIC REQUIREMENTS: CLASSES OF INTEREST FOR KEY USERS (UPPER FIGURE), ASSOCIATE USERS (MIDDLE FIGURE) AND BROAD USERS (LOWER FIGURE) FIGURE 33: THEMATIC REQUIREMENTS: CLASSES OF INTEREST FOR LAND DYNAMIC MONITORING FOR KEY USERS (UPPER FIGURE), ASSOCIATE USERS (MIDDLE FIGURE) AND BROAD USERS (LOWER FIGURE, GREY STRIPED CLASSES WERE NOT ASKED) FIGURE 34: MOST CONVENIENT DATA FORMATS FOR DATA DELIVERY FIGURE 35: MOST CONVENIENT DATA DELIVERY MODE UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

9 2.rev.2 22/02/ List f tables TABLE 1: KEY TASKS FOR LAND COVER THEME DEFINED IN THE GCOS IMPLEMENTATION PLAN (2004 AND 2010), PROGRESS REPORTED IN 2009 (FOR COP 15 IN COPENHAGEN), AND HOW THESE TASKS ARE TAKEN UP BY LAND COVER CCI PROJECT TABLE 2: GCOS REQUIREMENTS FOR LAND COVER ASSESSMENT WITH REGARD TO CURRENT PERFORMANCE CAPABILITY (SOURCE: ESA 2009) AND PRECURSOR PRODUCTS (BASED ON MERIS, MODIS AND SPOT-VGT TIME SERIES) EXPERIENCE TABLE 3: CHARACTERISTICS OF LAND COVER MAPPING AND MONITORING PRODUCTS USEFUL FOR OBSERVING LAND COVER AS AN ECV (ADOPTED FROM HEROLD ET AL., 2009) TABLE 4: REQUIREMENTS FOR SATELLITE LAND COVER PARAMETERS DERIVED FROM CMUG USER ASSESSMENT REPORT (CMUG 2010) TABLE 5: COMPARISON OF GCOS (GCOS-107, WMO DATABASE), CMUG (CMUG 2010), AND CCI REQUIREMENTS (SOURCE: CCI PROJECT MEETINGS) TABLE 6: MODEL PARAMETERS TO BE VALIDATED USING LAND COVER PRODUCTS AND RELATED OBSERVATION DATA. IN BOLD THE PARAMETERS ARE GIVEN THAT ARE MENTIONED MOST TABLE 7: THE LEVEL OF DETAIL REQUIRED TO VALIDATE MODEL PARAMETERS BY MEANS OF LAND COVER PRODUCTS TABLE 8: MATRIX OF THE SIMILARITY BETWEEN THE 12 GENERALIZED LAND COVER CLASSES AS AVERAGE FOR 9 LAND SURFACE MODEL PARAMETERS TABLE 9: NEAR-TERM AND LONG TERM REQUIREMENTS TO IMPROVE EARTH SYSTEM MODELING (HIBBARD ET AL. 2010) TABLE 10: GLOBAL CLIMATE MODELING GROUPS (RESPONDING USERS INDICATED WITH *) TABLE 11: REGIONAL CLIMATE MODELING GROUPS (RESPONDING USERS INDICATED WITH *) TABLE 12: LAND CARBON MODELING GROUPS (RESPONDING USERS INDICATED WITH *) TABLE 13: HYDROLOGY CARBON MODEL GROUPS (RESPONDING USERS INDICATED WITH *) TABLE 14: NUMERICAL WEATHER PREDICTION GROUPS (RESPONDING USERS INDICATED WITH *) UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

10 2.rev.2 22/02/ List f acrnyms CCI: CEOS WGCV: CMUG: DGVM: ECV: EO: ESM: FCDR: GCM: GCOS: GEO: GOFC-GOLD: GTOS: IAM: IGCO: IGOL: IPCC: LCCS: LCML: LSCE: MPI-M: MOHC: NWP: PFT: RCM: UNFCCC: Climate Change Initiative Cmmittee n Earth Observatin Satellites Wrking Grup n Calibratin and Validatin Climate Mdelling User Grup Dynamic glbal vegetatin mdel Essential Climate Variable Earth Observatin Earth System Mdeling Fundamental Climate Data Recrd General Circulatin Mdels Glbal Climate Observing System Grup n Earth Observatin Glbal Observatins f Frest and Land Cver Dynamics Glbal Terrestrial Observing System Integrated Assessment Mdeling Integrated Glbal Carbn Observatin Integrated Glbal Observatins fr Land Intergvernmental Panel n Climate Change Land Cver Classificatin System Land Cver Macr Language Labratire des Sciences du Climat et de l Envirnment Max Planck Institute fr Meterlgy Meterlgical Office Hadley Center Numerical weather predictin Plant Functinal Type Reginal Climate Mdeling United Natins Framewrk Cnventin n Climate Change UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

11 2.rev.2 22/02/ Backgrund and scpe This dcument describes the activities and results fr the user requirement analysis (WP1100) fr the prduct specificatin as part f the Land Cver CCI prject within ESA s Climate Change Initiative Prgram. The verall bjective fr the Land Cver CCI prject is t critically revisit all algrithms required fr the generatin f a glbal land prduct in the light f the GCOS requirements, and t design and demnstrate a prttype system delivering in a cnsistent way ver years and frm varius EO instruments glbal land cver infrmatin matching the needs f key users belnging t the climate change cmmunity. In the first stage f the prject, the detailed specificatins f a glbal land cver prduct will be defined which matches the requirements frm GCOS (bth fr itself and as a surrgate fr ther imprtant climate variables) and key climate users, and which is achievable n a regular basis using the current EO systems and building n the UN Land Cver Classificatin System (LCCS) fr cnsistency and interperability with ther land cver prducts. T d s, key climate and carbn mdeling users will be cnsulted t ensure the develped Land Cver prducts meet the requirements fr a range f mdel cmmunities and fr applicatin f existing and future mdeling appraches (WP1100). The verall bjective f WP1100 is: 1. t establish an user dialg and interactin with climate mdel users; 2. t identify user needs fr prduct specificatins. The tasks carried ut fr WP1100 are: 1. Prvide a brad review f climate mdeling user requirements frm the scientific literature including existing uses f land cver data fr climate mdeling and thrugh assessing GCOS and GTOS requirements including the updated versin f the GCOS implementatin plan available frm August 2010; 2. Implement a survey f the prject assciated users and their requirements and related synthesis t derive prduct specificatins; 3. Participatin in the CMUG prcess and attending key upcming meetings and cnference fr active engagement in scientific dialgs amng climate change mdeling cmmunity, i.e., n harmnizatin effrts fr land cver amng different cmmunities; 4. Prvide cntributins and lead f discussins fr a user interactin and prduct specificatin activities within the prject. This technical reprt gives an verview f the cncepts and backgrund f the user requirements assessment as described in chapter 1 f this dcument. In chapter 2 f this dcument, the methdlgy and user engagement mechanism are described. Chapter 3 prvides the utcme f the user requirement assessment: here current and future requirements fr specificatins f a glbal land cver prduct which can prvide the climate variables imprtant fr land cver mnitring are given. These utcmes are presented accrdingly: the defined requirements frm GCOS and ther strategic earth bservatin dcuments are presented in sectin 3.1, fllwed by the utcmes f the user survey fr the brad land cver data use cmmunity (sectin 3.2). In sectin 3.3, the assessment f the climate mdeling cmmunity requirements is presented bth fr the key and assciated user grup and finalizing with the review n (future) requirements frm climate mdeling literature. In chapter 4, a UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

12 2.rev.2 22/02/ discussin n the results is presented including a synthesized advice fr land cver prduct specificatins and next generatin mdels Need fr cmmunity and user interactin t specify requirements fr ECV mnitring Issues f glbal, reginal and natinal frest and land cver bservatins have recently received significant attentin in a number f internatinal prcesses n the plitical level, ffering pprtunities t imprving relevance, acceptance, and appraches t peratinalize glbal and reginal land cver assessments. Since technlgical prgress and methdlgical sphisticatin alne is nt sufficient t implement glbal land assessments effectively, particular emphasize n fstering mre saliency and legitimacy f land cver bservatins is needed in additin t technical credibility. The effrts f Land Cver CCI prjects als address the issue t build a bridge between plicy requirements, and scientific prgress and cnsensus. It invlves engagement with prminent plitical prcesses, the gathering f bservatin requirements, prviding technical plicy advice, the definitin f bservatin strategies and pririties, evlving internatinal technical cnsensus n critical issues, the specificatin f implementatin guidelines, and implementatin f dedicated case studies fstering technical prgress, peratins and applicatins. These activities are prgressing in fur majr thematic areas: (a) standards fr land cver characterizatin, (b) standard methds fr land cver accuracy assessment, (c) glbal land cver bservatins and applicatins and (d) land cver change mnitring. As a prminent example, the current evlving activities t supprt the UNFCCC effrts fr research and systematic bservatins f Essential Climate Variables (ECV s) is taken shape int specific implementatin activities such as attempted in Land Cver CCI prject. While there is n detailed guidance n what it means t bserve land cver as ECV, there is guidance prvided frm the plitical level and its subsidiary technical bdies. The UNFCCC requiring glbal land cver bservatin prgress relates t research and systematic bservatins ((GCOS 2004, 2010b)). The scpe is t cntinuusly mnitr ECVs t reduce uncertainties in understanding the glbal climate system, which includes land cver as ne such variable. The related GCOS implementatin plan (GCOS tasks defined in 2004 have been redefined in 2010) specifies a number f specific tasks t imprve the glbal bservatin f land cver as an essential climate variable including (1) the establishment f internatinal standards, (2) cnsensus methds fr map accuracy assessment, (3) the cntinuity fr fine-scale satellite bservatins, (4) the develpment f an in situ reference netwrk and the implementatin f an peratinal validatin framewrk, (5) the generatin f annual glbal land-cver prducts, and (6) the develpment f a high-reslutin glbal land cver change dataset. As requested by the UNFCCC Subsidiary Bdy f Science and Technical Advise (SBSTA), reprting guidelines and standards are being develped fr each ECV including land cver. Prgress n this issue is dcumented at Fr bserving land cver as an ECV, several areas require attentin: The need t address the requirements f the UNFCCC; Prduct specificatins shuld be driven by the cre climate user cmmunities; The implementatin shuld fcus n a truly glbal system and prcess including: crdinated bservatins; integrated and standardized mapping; independent quality assessment. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

13 2.rev.2 22/02/ Any ECV mnitring effrt has t ensure saliency and legitimacy in additin t technical credibility. An internatinal crdinatin mechanism amng key actrs wrldwide (users, prducers, science, reginal/natinal experts) is essential t ensure that land cver prducts are accepted internatinally and by the UNFCCC. Such mechanisms are intrinsic t the land cver CCI prject and will be described in mre detail in chapter Land cver and climate mdeling Land cver and land cver change are becming mre and mre related t the climate mdeling effrt. Land cver change as a pressing envirnmental issue, is acting as bth a cause and a cnsequence f climate change (Figure 1). Reliable bservatins are crucial t mnitr and understand the nging prcesses f defrestatin, desertificatin, urbanizatin, land degradatin, lss f bidiversity, ecsystem functins, water and energy management, and the influence f land cver changes n the physical climate system itself. A number f disciplines (gegraphy, eclgy, gelgy, frestry, land plicy and planning, etc.) use and refer t land cver and land cver change as ne f the mst bvius and detectable indicatrs f land surface characteristics and assciated human induced and natural prcesses. Current IPCC Assessment Reprts are based upn an uncertain understanding f the land surface dynamics and related prcesses. Applicatins f land cver and land dynamics in climate change-related General Circulatin Mdels, Earth System Mdels and Impact Assessment Mdels need t be better linked and crdinated. The imprtance f these issues requires cntinuus mnitring systems and data. Climate/Oceans Emissins/sequestratin/albed (anthrpgenic & natural; GHG, trace gases, aersls) Climate/atmspheric cnditin (e.g., temperature, precipitatin, cluds, zne, CO 2, nutrients) Land-use/general ecnmic activity & mitigatin Land-use, land-use change, & water use Land-use & water endwment & ptential Terrestrial ecsystems Figure 1: Rle f land in lng-run (e.g., centennial) climate mdeling (Rse et al. 2008) All mdels are driven by data, whether that data is derived frm bundary cnditins r thrugh parameter estimatin, empirical relatinships r direct bservatins. In the end, mdel estimates, and, therefre, mdel errr, reflects the infrmatin, r analyses that is used t establish initial cnditins, parameter estimatin r internal algrithms. Fr instance, land-use change emissins are highly uncertain t within a factr f 4, i.e. 500 t 2700 TgC/y (Denman et al. 2007). This restricts ur ability t estimate the strength f glbal carbn sinks; althugh fssil fuel emissins and atmspheric CO 2 cncentratins are well-cnstrained, the large uncertainty in land-use change emissins means that the airbrne fractin f ttal emissins (and hence the fractin f ttal emissins taken up by land ecsystems and ceans) cannt be cnstrained s well. Similarly, glbal land cver as prvided by the UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

14 2.rev.2 22/02/ United Natins Fd and Agriculture Organizatin (FAO) is ften incnsistent with land-cver data and actual practices (e.g., the extent f glbal plantatin frests is uncertain). Fr adequate mdeling f prcesses at the land surface bundary t the atmsphere, an accurate representatin f the land surface is necessary. A climate mdel used t simulate these prcesses requires a prper determinatin f the land surface characteristics that are used in its parameterizatins as bundary cnditins. These parameters include, e.g., backgrund surface albed, surface rughness length due t vegetatin, fractinal vegetatin cver and Leaf Area Index (LAI), frest rati, plantavailable sil water hlding capacity, and vlumetric wilting pint. Three majr cmmunities, the General Circulatin Mdels (GCM), Earth System Mdeling (ESM), and the Integrated Assessment Mdeling (IAM) cmmunity play an imprtant rle in understanding and quantifying Earth and climate system analysis and specifically, understanding the rle f land use and land cver change. These different mdel cmmunities cmmnly have a glbal scpe f sme kind but fcus n different set f bjectives (Figure 2). A variety f appraches t addressing land use and land cver change have been cnsidered by these mdeling cmmunities. General circulatin mdels (GCMs) include a rather carse level f eclgical and bigechemical prcess representatin and use land cver as generic and fixed bundary cnditin. Earth system mdel (ESM) mdelers have taken an apprach that stems frm a cmbinatin f basic ecsystem (e.g., carbn cycle) and dynamic glbal vegetatin mdels (DGVMs), and that incrprates different plant functinal types (PFTs) int their mdel structures. These aspects f ESMs are increasingly being used fr impacts assessments, bth fr ecsystems themselves and the impacts n hydrlgy which are mdified by ecsystem respnses. The ESM apprach is derived frm a traditin f using cmplex mdels t analyze the different cmpnents and interactins f the physical system. The fcus has mainly been n the climate system, with an initial descriptin f cupled cean-atmsphere systems, and mre recently the carbn cycle and dynamic vegetatin. By extending its fcus, the ESM apprach is mreand-mre implementing cupled climate with hydrlgy, agriculture and urban systems as integral cmpnents f the Earth system. Figure 2: The multi-scale and multi-purpse nature f climate and carbn mdels, i.e. sil, ecsystem, dynamic glbal vegetatin mdel (DGVMs), and general circulatin mdels (GCMs): scales f predictin and prcess reslutin. Shwing that the level f detail in prcess reslutin generally diminishes as the predictive scale (spatial and tempral) f the mdel increases (frm Ostle et al., 2009) UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

15 2.rev.2 22/02/ A number f ESM appraches have been develped ranging frm GCMs that perate at the 2nd glbal grid cell scale t sil carbn prcess mdels that can be parameterized at the plt scale (Figure 2). DGVMs are the main linking cmpnent t extraplate the highly detailed prcess representatin t the glbal level by including the state-f-the-art knwledge abut the impacts f change n plant-sil interactins and their feedbacks n the climate system. A brad range f DGVMs f varying degrees f cmplexity is currently being adpted within ESM: CLM-CN, CLIMBER, JSBACH, IGSM, LPJ, BIOME-BGC, CENTURY, DNDC, HYBRID, SDGVM, TRIFFID, ORCHIDEE (Ostle et al. 2009). Mst DGVMs utilize the cncept f plant functinal types (PFTs: numbering between 3 and 20) t characterize glbal (vegetatin) land cver diversity. Each PFT represents a brad class f vegetatin type such as deciduus frest r grassland and is parameterized fr a cre set f physilgical prcesses and eclgical phenmena. The IAM apprach cmes largely frm a traditin f mdeling human behavir explicitly and the interactin f human activities, decisin making and the envirnment, including ecnmic prductin and cnsumptin, energy systems, greenhuse gas emissins and land-use. This cmmunity has als recgnized the imprtance f land use as a critical factr in sci-ecnmic decisin making, fr example fr fd and timber prductin, the state f ecsystems and their services, and increasingly, as a respnse t demand fr bifuels fr the electricity and transprtatin sectrs. While many IAMs have fcused strngly n energy-ecnmy systems and nly included land use emissins as exgenus factrs, this is nw changing with the develpment and implementatin f increasingly cupled sciecnmic and climate mdeling strategies User engagement mechanism Several actrs and types f users will be invlved in representing the mdeling cmmunities cncerned with climate and climate change issues. The structure t ensure a cntinuus dialgue with the climate cmmunity in different phases f executin fr the Land Cver CCI prject includes three main phases: 1. Identificatin f specific user needs fr prduct specificatins (WP 1100): a. Brad review f user requirements frm the scientific literature including existing uses f land cver data fr climate mdeling but als n innvative cncepts and appraches t better reflect land dynamics in the next generatin f mdels. This includes a detailed survey f the prject key and assciated users and their requirements and related synthesis t derive prduct specificatins; b. Participatin in the CMUG prcess and attending key upcming meetings and cnference; c. Active engagement in scientific dialgs amng climate change mdeling cmmunity, i.e. n harmnizatin effrts fr land cver amng the ESM and IAM cmmunities. 2. Critical user review f the land cver CCI prductin prcess and implicatins fr specificatins (WP 3500): a. Selected users will be invited t participate the prduct develpment, implementatin and validatin and asked t prvide input and feedback at different pints during the prcess. 3. User applicatin and feedback mechanism frm the users n the use f the prducts and related ptentials and limitatins (WP ): UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

16 2.rev.2 22/02/ a. Key users will be asked t use the prducts generated in their applicatins t prvide first indicatins n the ptentials and limitatins; b. Final discussins with the users will yield feedback n the prducts and results in a set f recmmendatins t further imprve ECV land cver mnitring beynd this prject. The purpse f this reprt is t present the experiences and results f the first step nted abve and mre detailed in Figures 3 and 4. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

17 2.rev.2 22/02/ Figure 3: Cncept f user requirement assessment as part f the verall breakdwn structure f Land Cver CCI prject UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

18 2.rev.2 22/02/ Types f users representing the climate mdel user grups Several actrs and types f users can be identified as representatives f the mdeling cmmunities cncerned with climate and climate change issues. Ptential users that define mdel requirements riginate frm grups specialized in different fields f science: e.g., wrking in weather predictin, Glbal Circulatin Mdeling (GCM), Reginal Climate Mdeling (RCM), Glbal and Reginal Earth System mdeling, Carbn Cycle Mdeling, Dynamic Vegetatin and Hydrlgy mdeling and thers. Ptential users f the new land cver prducts are als mdel develpment applicatin grups wrking in numerical weather predictin (NWP), GCMs and RCMs, glbal and reginal Earth System mdels, carbn cycle mdels and dynamic vegetatin and hydrlgy mdels. With regard t climate and ESM, this cmprises (1) grups participating in the glbal and reginal (CORDEX) IPCC activities fr the frthcming 5 th assessment reprt and (2) grups participating in the EU prjects ENSEMBLES ( and PRUDENCE With regard t hydrlgy mdels, ptential users are grups participating in the EU prject WATCH ( and the assciated WaterMIP (Water Mdel Intercmparisn Prject). NWP grups invlve natinal weather services as well as the Eurpean Centre fr Medium-Range Weather Frecast (ECMWF). The list f such ptential users is prvided in Appendix D. Frm this large array f different users, mdel usage can be cnceptualized at a different levels f mdel engagement: 1. Key users: they are central t all phases f the user interactin within the prject and are integral part as partners in the prject. They are the Max Planck Institute fr Meterlgy (MPI-M), the Labratire des Sciences du Climat et de l Envirnnment (LSCE) and the Meterlgical Office Hadley Center (MOHC). Key users are directly invlved in the prduct specificatins, prduct assessment and the final user assessment f the prduct. Mst f these users are als member f the CMUG. 2. Assciated users: These users maybe participating in meetings and in the user survey and their input wuld feed int the prduct specificatins. These users are nt partners in the prject directly but culd be engaged, in particular if invlved in the user assessment f the prducts. This grup is described in the list f Appendix D. 3. Brad user cmmunity: will be cnsidered thrugh infrmatin f the prject thrugh the Wrld Wide Web and thrugh reviewing scientific literature, participatin in meetings t synthesize requirements fr the prduct specificatins and thrugh receiving feedback frm general glbal land cver data users. This grup f users wuld als include knwn user requirements cming nt directly frm climate mdelers but the climate cncerned users such as thse making use f land cver infrmatin fr ther scietal benefits r natinal reprting and accunting. The user cnsultatin will address a brad range f issues due t the nature f the interactins f land cver and climate. Cnsequently, land cver user requirements fr climate mdeling and climate research are expected t be diverse and this cmplexity is reflected in the user cnsultatin plan as presented in Figure 3 and detailed ut in the next sectins. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

19 2.rev.2 22/02/ Methdlgy The Land Cver CCI prject is based n the prgress that has been made in terms f land cver characterizatin and validatin prcedures and addresses critical tasks which have nt achieved sufficient prgress up t date. The plan fr a thrugh and cmplete user requirements analysis fr develping the final prduct specificatins uses a range f surces and mechanisms. There are als different levels f hw users representing the climate research cmmunity will be invlved in this prcess (Figure 4). Figure 4: Overview f the user requirement assessment methdlgy fr cnsultatin f the climate mdeling cmmunity UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

20 2.rev.2 22/02/ Brad assessment f user requirements As indicated in the previus sectin, several actrs and types f users are invlved in representing the mdeling cmmunities cncerned with climate and climate change issues. The user cnsultatin dialgue (Figure 4) fr Land Cver CCI was crdinated by WUR in clse cperatin with the Hadley Center (UK) that is represented in CMUG. The brad assessment f existing mdels and user requirements aims at lking, int the range f appraches, hw land cver data have been used in climate mdels. This assessment includes different mdeling appraches and cmmunities, i.e. Glbal Circulatin Mdels, Earth System Science mdels, Climate predictin and frecasting mdels, and integrated Impact Assessment Mdels. The fllwing activities have been carried ut fr the brad user assessment: 1. The analysis f strategic earth bservatin dcuments f relevance: a. GCOS requirements as presented in the GCOS Implementatin Plan 2004 (GCOS 2004), and GCOS Implementatin Plan 2010 (GCOS 2010b); b. GCOS Principles and Needs derived frm Guideline fr the Generatin f Datasets and Prducts Meeting GCOS Requirements (GCOS 2010a); c. GTOS requirements, (Herld et al. 2009), GTOS d. CMUG requirements (CMUG 2010); e. IGOS-P themes n land (Twnshend 2008), IGOS-P_IGOL f. IGOS carbn theme, (Ciais and Mre 2004) 2. Detailed literature review f land cver representatin in climate mdeling, land cver parameterizatin appraches and studies that lked int the impact f land cver data n climate mdeling results. 3. Brad land cver prduct user survey: user survey n requirements fr next generatin land cver prducts with special attentin fr climate and earth system mdeling issues under the user cmmunity fr the ESA GlbCver prduct. The set-up and questins fr this survey are presented in Appendix A. This brad assessment f user requirements ensures that the full range f needs are cnsidered and understd fr deriving the detailed prduct specificatins Key user requirements cnsultatin The secnd step in the user cnsultatin prcess fr the prduct specificatins included the partners and prcesses directly invlved r assciated with the ESA CCI prgram and Land Cver CCI prject. The aim was t prvide a detailed user needs assessment and identify specific requirements cming frm the key users f land cver prducts f the prject. Three main mechanisms have been carried ut fr user cnsultatin f the key and assciated users (sectin 1.4) f the climate mdeling cmmunity: 1. Participate in the CMUG prcess by active cntributin t the ESA c-lcatin meeting; UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

21 2.rev.2 22/02/ An user interactin and prduct specificatin meeting was executed ut as part f the prject with representatin f key users t discuss the Land Cver CCI prduct characteristics as dialg amng users and prducers; 3. A detailed user survey was cnducted n the specific requirements fr land cver data characteristics t be used (e.g., spatial, tempral, thematic detail, accuracy requirements). The detailed survey fr the key-users (Appendix C was cnducted thrugh while fr the assciated users a mre cncise survey was prepared (Appendix B) which was made available t the cmmunity (Appendix D) as an nline survey. The cmpsitin f the tw user grups has been described in sectin 1.4. This part f the user cnsultatin has prvided the requirements based n existing mdel applicatins requiring land cver data and future needs as identified by this cmmunity. These users will als frm the primary partners in the user validatin and assessment phase t evaluate the Land Cver CCI prducts in dedicated mdel applicatins during next phases f the prject Next generatin mdel requirements In the final step, the user cnsultatin targeted at the set f requirements fr the next generatin mdels. This is driven by the ntin that the CCI prducts will need t cnsider nt nly tday s but future user requirements. New mdeling cncepts have triggered discussin t imprve the existing land cver characterizatin and parameterizatin cncepts. Imprved bservatins addressing a range f requirements can play an imprtant rle in that prcess and, therefre, the utcmes presented will als cnsider user requirements f the next generatin mdeling appraches. This has been implemented thrugh an active engagement in scientific dialgs amng the climate mdeling cmmunity, i.e., n harmnizatin effrts fr land cver amng the ESM and IAM cmmunities and n imprved cncepts f land cver parameterizatin (Hibbart et al., 2010). Furthermre, the user requirements f the next generatin mdeling appraches have been distilled frm a brad array f (scientific) literature. And finally, sme specific questins in the key and assciated user surveys were referring t land cver requirements fr future climate mdeling cncepts. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

22 2.rev.2 22/02/ Results f user cnsultatins The verall bjective f the brad user requirement assessment is t identify hw land cver data is currently used by the climate mdeling cmmunity and what the future requirements fr land cver data are fr climate and earth system mdeling. In this chapter, first (sectin 3.1) sme cre chapters n land cver mnitring frm leading strategic earth bservatin dcuments are presented. The GCOS requirements n land cver data are prvided frm the GCOS implementatin plan 2004 and frm the updated versin f Fr cmpleteness, the GCOS needs and principles n land cver data are als presented. Furthermre, the GTOS requirements n ECV land cver data standardizatin framewrks are given, fllwed by the CMUG, IGOS-P requirements fr the Land and Carbn theme and the Integrated Glbal Carbn Observatin (IGCO). In sectin 3.2 the results f the brad user survey are summarized an visualized. This brad assessment f user requirements ensures that the full range f needs are cnsidered and understd fr deriving the detailed prduct specificatin. The results are displayed belw accrdingly. Sectin 3.3 prvides the results f the assessment f the climate mdeling cmmunity requirements. This includes the results f the key and assciate user cnsultatin (3.3.1 and 3.3.3). Sectin prvides the summary f the cmparisn f mdel parameters versus land cver. Furthermre, sectin includes a literature review including issues n land cver representatin in climate mdeling, land cver parameterizatin appraches and studies that lked int the impact f land cver data n mdeling results Analysis f GCOS and ther earth bservatin strategic dcuments GCOS implementatin plan and accuracy needs The Glbal Climate Observing System (GCOS) is a jint undertaking f the Wrld Meterlgical Organizatin (WMO), the Intergvernmental Oceangraphic Cmmissin (IOC) f the United Natins Educatinal Scientific and Cultural Organizatin (UNESCO), the United Natins Envirnment Prgramme (UNEP) and the Internatinal Cuncil fr Science (ICSU). In cnsultatin with its partners, GCOS has prepared tw implementatin plans (GCOS_IP 2004, GCOS_IP 2010) that addresses the requirements identified in the Secnd Reprt n the Adequacy f Glbal Observing Systems fr Climate in Supprt f the United Natins Framewrk Cnventin n Climate Change (UNFCCC). This Plan, if fully implemented by the Parties bth individually and cllectively, will prvide the glbal bservatins f the Essential Climate Variables and their assciated prducts, t assist the parties in meeting their respnsibilities (under Articles 4 and 5) f the UNFCCC. In additin, it will prvide many f the essential bservatins required by the Wrld Climate Research Prgramme (WCRP) and Intergvernmental Panel n Climate Change (IPCC). UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

23 2.rev.2 22/02/ Table 1: Key tasks fr land cver theme defined in the GCOS Implementatin Plan (2004 and 2010), prgress reprted in 2009 (fr COP 15 in Cpenhagen), and hw these tasks are taken up by Land Cver CCI prject GCOS Implementatin Plan task (2004) Actin T22 Internatinal standards fr land cver maps In IP 2010, T22 was remved Actin T23 Methds fr land cver map accuracy assessment In IP 2010, defined as T26 Actin T25 Develpment f in situ reference netwrk fr land cver In IP 2010, T22 is reflected in ecsystem bserving netwrk Actin T26 Annual land cver prducts In IP 2010, defined as T27 Actin T27 Regular finereslutin land cver maps and change In IP 2010, defined as T28 Status reprted in recent prgress reprt (2009) The UN LCCS (under ISO) prvides the required standards and specificatins (gd prgress). Standard validatin prtcls, methds and best practices have been develped by the CEOS Wrking Grup n Calibratin and Validatin (WGCV), wrking with GOFC- GOLD (gd prgress). As a start, GOFC-GOLD and CEOS WGCV have develped the framewrk fr an in situ reference netwrk fr peratinal glbal land cver validatin. (lw prgress) There are several glbal land cver prducts at the requested reslutin including GlbCver and MODIS (mderate prgress) N cncerted actin twards a glbal prduct at the required fine reslutin (10-30 m) has been achieved (lw prgress) Issues addressed by Land Cver CCI LCCS classifiers, generic classes and related legends targeted at user requirements will be used t develp the prduct The prject is using a cmprehensive validatin apprach that is independent, internatinally agreed and repeatable. Fr the prduct validatin, a cmprehensive apprach making best use f existing resurces and aiming at develping an peratinal reference netwrk is applied The activities are building upn the GlbCver heritage, cperating with the MODIS team, and aiming at annual glbal prducts. The issue f fine-scale land cver/land cver change is nt specifically addressed here while sme methdlgical steps culd be extended t higher reslutin data set. As a starting pint fr the Land Cver CCI prject, activities have been clsely aligned with specific land cver tasks listed in the GCOS Implementatin Plan f 2004 (GCOS 2004) (Table 1). In this plan, tasks were already listed which were an answer t up till then defined mdel requirements: the need t harmnize land cver mnitring (GCOS task 22), validatin f mdels (GCOS task 23), mdel quality assessment (GCOS task 25), and the need fr an annual land cver prduct (GCOS task 26). This user requirement assessment will build upn this heritage, in rder t fully capture the requirements needed t mdel the imprtant climate variables fr land cver mnitring. The implementatin needs t be building upn prgress made t define standards fr characterizing land cver and fr validatin prcedures (GCOS Implementatin Plan, tasks 22 and 23). The prject further addresses critical tasks that have nt achieved sufficient prgress t date, i.e., n the implementatin f an peratinal reference netwrk and validatin, and t create annual maps f glbal land cver. These critical tasks are taken up in the GCOS Implementatin Plan 2010 (GCOS 2010b). The fllwing paragraphs explain the different GCOS tasks in mre detail. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

24 2.rev.2 22/02/ Harmnized land cver mnitring (T22, IP 2004 ) There is need fr bth maps (static and updated) and dynamic mnitring prducts. The develpment and derivatin f the mapping prducts need cnsistency in land cver characterizatin t be interperable as part f an integrated glbal bserving system. The brad areas and tpics requiring internatinal cnsensus are utlined in the GTOS dcument n standards fr bserving land cver as ECV with fcus n the thematic prduct ((Herld et al. 2009), GTOShttp:// T09.html). This dcument emphasizes that land cver is defined as the bserved (bi)-physical cver n the Earth s surface, see als the sectin n the GTOS requirements. It includes vegetatin and manmade features as well as expsed rck, bare sil and inland water surfaces. The primary units fr characterizing land cver are categries (such as frest r pen water) r cntinuus variables classifiers (e.g. fractin f tree canpy cver). The UN LCCS classifiers ( prvide a cmprehensive and flexible framewrk fr thematic land cver characterizatin. LCCS classifiers enable better cmpatibility t be achieved between existing datasets and fr future glbal mnitring systems. This issue will be particularly imprtant fr the legend develpment f the ECV Land Cver prduct. The definitin f the target legend is cnstrained by three issues. It is dependent n the purpse f applicatin f the land cver map, in this case land cver parameterizatin fr the targeted user cmmunities and their mdel requirements. Different user grups may have different requirements that will be assessed as part f the prject. Secndly, the LCCS classifier cncept is t be used as suggested by GTOS (Herld et al. 2009). Thirdly the infrmatin fr all desired classes must be available and separable frm the input bservatin data sets t derive a prduct f sufficient quality. There is als a need t ensure synergy with ther ECV bservatin prducts (i.e. Fire, Biphysical Parameters, Snw Cver) that are directly related t land cver characteristics. Validatin (T23, IP 2004/ T26, IP 2010) The thematic validatin f the prducts is required t be n independent nature, fllws internatinal standards where existing and uses existing references datasets and related experiences as much as pssible. Hwever, the independent accuracy assessment fr mnitring land cver as ECV pses additinal requirements and challenges. The validatin exercise needs t explre the ptins t perfrm validatins fr multiple dates in time. Fr histrical perids the availability f reference data sets (i.e. fr the 1990 s) is rather limited. Fr the future there is need t develp the fundatins and start implementing n peratinal mnitring that ensures that prgressing annual glbal land cver datasets can assessed cnsecutively. Fr the validatin f land cver change, different prtcls and appraches will need t be used. Independent quality assessment (T25, IP 2004) There is need fr an independent quality assessment t ensure that the required standards are met, and that uncertainties are quantified and reduced as far as practicable. While diversity and redundancy is useful fr building a sustained glbal land cver mnitring system and t ensure flexibility in incrprating evlving technlgies, there als needs t be an independent assessment mechanism led by the internatinal cmmunity. This mechanism shuld prvide a cmparative assessment and validatin f individual prducts and wrk twards synergy t ensure that a cmmn framewrk is used fr glbal assessments, and that the best glbal estimates are made available based n the current stage f knwledge, data and infrmatin. The basis fr such effrts cnsists f sustained glbal netwrk f calibratin and validatin sites, internatinal agreement and standards and appraches fr land cver characterizatin and validatin, and an internal crdinatin mechanism, currently lead by GOFC-GOLD and the Land Validatin sub-grup f the CEOS WGCV. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

25 2.rev.2 22/02/ Table 2: GCOS Requirements fr land cver assessment with regard t current perfrmance capability (surce: ESA 2009) and precursr prducts (based n MERIS, MODIS and SPOT-VGT time series) experience GCOS requirements Current status VEGETATION MERIS MODIS Class accuracy (max. errr fr individual classes) Spatial reslutin 15% missin / cmmissin per class 250m-1km GLC % weighted acrss all classes GlbCver 74 % weighted acrss all classes MODIS v5 75% verall accuracy 1 km 300m 500m Gemetric accuracy Better than 1/3 IFOV 300m 70m m Tempral reslutin 1 year bserving cycle Yearly 2000 Yearly Yearly 2002 t 2009 Stability As class accuracy Nt specified N inter-cmparisn pssible Annual land cver prducts (T26, IP 2004/ T27 IP 2010) Several glbal land cver prducts are currently available at the requested reslutin including GLC2000, GlbCver and MODIS land cver prducts. Existing glbal land cver prducts partially meet the GCOS requirements in terms f perfrmance, as illustrated in Table 2. It indicates that nne f the available land cver prducts meet the requirements expressed by GCOS in terms f class accuracy and stability. The Land Cver CCI activities are building upn the GlbCver heritage, cperating with the MODIS team, and aiming at cnsistent annual glbal prducts. Particular attentin will be paid t these tw issues, by making the best use f spectral and tempral infrmatin cntent in existing EO time series (thrugh suitable pre-prcessing and classificatin prcesses) and by specifically addressing the issue f inter-annual stability. Yet, it has t be stated that nt all land cver classes have the same imprtance frm a climate mdeling perspective. T this end, the prject will als require the definitin f a legend. Accrding t GCOS, a cmmn language fr class definitin shuld be used, and thematic detail shuld be reginally adapted in rder t satisfy requirements f internatinal cnventins, and as far as pssible be harmnized with reginal classificatin schemes presently in use (See the Annex J n Land Cver f the CCI statement f wrk (EOP-SE 2009b, a). Furthermre it is expected that the prduct stability ver time will be strngly affected by the intrinsic quality f the EO time series available fr a given perid. With respect t the ptential spatial reslutins required by mdelers and with respect t the key assciated issues that need t be cnsidered in the ECV develpment in respect f the mdel needs, the fllwing GCOS prduct framewrk is prvided (see Figure 5) (EOP-SE 2009a). Hereby, the key principle f cnsistency acrss spatial scale, time and between ECVs shall be paramunt. The land cver prduct definitins must accrdingly cncentrate principally n the determinatin f land cver using MERIS FR and RR and VEGETATION data and in merging these data. Hereby, VEGETATION data shall be used frm 1998 t UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

26 2.rev.2 22/02/ A merged VGT and MERIS RR prduct shall be develped frm 2002 nward. Frm 2005 nward MERIS FR shall be used in pririty in rder t get the high reslutin benefits (accuracy target) in cncmitance with spectral infrmatin cming frm VEGETATION and mre data cming frm MERIS RR. Figure 5: GCOS prduct framewrk cnsidering ptential spatial reslutins required by mdelers and key assciated issues that need t be cnsidered in the ECV develpment with respect t the climate mdeling needs GCOS principles General guidance fr the generatin f Fundamental Climate Data Recrds (FCDRs) and derived ECV prducts based n surface-based, airbrne and satellite-based bserving systems, and subsequent quality assessment by prviders as well as users, is given by the GCOS requirements explained in the previus sectin as recmmended in the GCOS_IP 2004 (GCOS 2004) and its 2010 update GCOS_IP 2010 (GCOS 2010b) and the Satellite Supplement (see fr an verview f all dcumentatin related t GCOS needs verview GCOS climate bservatin needs). These requirements are based n a brad cnsensus by the internatinal climate cmmunity; and are reviewed n a regular basis. As part f this, t ensure full dcumentatin, transparency and scientific stewardship in the generatin (and update) f FCDRs and ECV prducts, the GCOS Steering Cmmittee recmmends that data prducers pay particular attentin t the 12 needs enumerated belw and prvided in the Guideline fr the Generatin f Datasets and Prducts Meeting GCOS Requirements (GCOS 2010a). GCOS Principles and Needs 1. Full descriptin f all steps taken in the generatin f Fundamental Climate Data Recrds FCDRs and ECV prducts, including algrithms used, specific FCDRs used, and characteristics and utcmes f validatin activities; 2. Applicatin f apprpriate calibratin/validatin activities; UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

27 2.rev.2 22/02/ Statement f expected accuracy, stability and reslutin (time, space) f the prduct, including, where pssible, a cmparisn with the GCOS requirements; 4. Assessment f lng-term stability and hmgeneity f the prduct; 5. Infrmatin n the scientific review prcess related t FCDR/prduct cnstructin (including algrithm selectin), FCDR/prduct quality and applicatins; 6. Glbal cverage f FCDRs and prducts where pssible; 7. Versin management f FCDRs and prducts, particularly in cnnectin with imprved algrithms and reprcessing; 8. Arrangements fr access t the FCDRs, prducts and all dcumentatin; 9. Timeliness f data release t the user cmmunity t enable mnitring activities; 10. Facility fr user feedback; 11. Applicatin f a quantitative maturity index if pssible; 12. Publicatin f a summary (a webpage r a peer-reviewed article) dcumenting pint-by-pint the extent t which this guideline has been fllwed GTOS requirements The Glbal terrestrial Observing System (GTOS) is a prgramme fr bservatins, mdeling, and analysis f terrestrial ecsystems t supprt sustainable develpment. GTOS facilitates access t infrmatin n terrestrial ecsystems s that researchers and plicy makers can detect and manage glbal and reginal envirnmental change. GTOS and FAO define land cver as the bserved (bi)- physical cver n the Earth s surface. It includes vegetatin and man-made features as well as expsed rck, bare sil and inland water surfaces. The primary units fr characterizing land cver are categries (such as frest r pen water) r cntinuus variables classifiers (e.g., fractin f tree canpy cver). Secndary utputs f land cver characterizatin include surface area f land cver types (hectares), land cver change (area and change trajectries), and bservatin by-prducts such as field survey data r prcessed satellite imagery. With respect t land cver mnitring, the recent GTOS reprt (Herld et al. 2009) presenting suggestins fr mre systematic and standardized acquisitin f ECV s prvides the current summary fr the level f standardizatin and desired bservatins as a general assessment f the UNFCCC requirements and needs (see als Figure 5). GTOS emphasizes the need fr crdinated bservatins. An peratinal glbal land cver mnitring integrates infrmatin frm different bservatin scales, i.e. integrating carse and fine scale satellite data and in situ data. ECV mnitring assumes the use f all useful data surces - frm histrical archives, present assets and future mnitring prgrammes in a seamless and cnsistent manner. Acquisitins and the derivatin f standard prducts shuld be crdinated amng space agencies (e.g., with supprt f GEO, CEOS). UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

28 2.rev.2 22/02/ Table 3: Characteristics f land cver mapping and mnitring prducts useful fr bserving land cver as an ECV (adpted frm Herld et al., 2009) Integrated and standardized mapping and mnitring refers t the need n static and updated maps and dynamic mnitring prducts at different spatial and tempral scales. These utputs require different sets f bservatins and mnitring appraches. The develpment and derivatin f the mapping prducts need cnsistency in land cver characterizatin t be interperable as part f an integrated glbal bserving system. The brad areas and tpics requiring internatinal cnsensus are utlined in the GTOS dcument n land cver (Herld et al. 2009). There is als a need t ensure synergy with ther ECV bservatin prducts (i.e. Fire, biphysical parameters, Snw Cver) that are directly related t land cver characteristics. The issue f independent quality assessment fllws the need t ensure that the required standards are met, and that uncertainties are quantified and reduced as far as practicable. Cnsidering the suite f imprtant land cver infrmatin (Figure 5), there is expected t be a diversity f prducts cntributing t ECV mnitring. While diversity and redundancy is useful fr building a sustained glbal land cver mnitring system and t ensure flexibility in incrprating evlving technlgies, there als needs t be an independent assessment mechanism led by the internatinal cmmunity. This mechanism shuld prvide a cmparative assessment and validatin f individual prducts and wrk twards synergy t ensure that a cmmn framewrk is used fr glbal assessments, and that the best glbal estimates are made available based n the current stage f knwledge, data and infrmatin. The basis fr such effrts cnsists f sustained glbal netwrk f calibratin and validatin sites, internatinal agreement and standards and appraches fr land cver characterizatin and validatin, and an internal crdinatin mechanism. One imprtant requirement in the GTOS and FAO related requirement is the fact that land cver infrmatin has t be cmpatible and cmparable fr multi-tempral analysis and map updates, within and amng cuntries, within and between applicatins, disciplines and agencies, and acrss lcal t glbal scales (vertical and hrizntal harmnizatin). In general, harmnizatin is a bttm-up UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

29 2.rev.2 22/02/ prcess f emphasizing similarities and reducing incnsistencies between existing definitins f land cver t allw fr better cmparisns and cmpatibility between varius land cver datasets (Herld 2006). Harmnizatin effrts shuld first address the terminlgy, r classifiers, used fr the descriptin f land cver and, nce applied t systems and legends, the individual criteria used fr creating land cver categries shuld be harmnized and applied in peratinal bserving prgrammes. The Land Cver Classificatin System (LCCS, (Di Gregri 2005)) and the related ntlgy specified in Land Cver Macr Language (LCML) is currently the mst cmprehensive, internatinally applied and flexible framewrk fr land cver characterizatin. It defines a system f diagnstic criteria (land cver classifiers) that prvides standardizatin f terminlgy and nt categries. At this level, existing land cver data can be much better cmpared. The Land Cver Data Macr Language is underging apprval t becme a standard f the Internatinal Standards Organizatin (ISO). A translatin f existing land cver legends and data int the LCCS language usually prvides the first step in develping understanding needed t apply the classifier cncept, and many existing glbal, reginal and natinal land cver legends have been develped r translated using LCCS (see An agreement n a set f recmmended classifiers prvides the cmmn grund fr cmpatibility f land cver data. Current internatinal cnsensus n classifiers that meet glbal mapping land cver requirements include: Vegetatin life frm: trees, shrubs, herbaceus vegetatin (may be separated int grasslands and agricultural crps), lichen and msses, nn-vegetated; Leaf type (needle-leaf, brad-leaf) and leaf lngevity (deciduus, evergreen) fr the different vegetatin life frms; Nn-vegetated cver types (bare sil r bare rck, built up areas, snw, ice, pen water); Density f life frm and leaf characteristics in percent cver; Terrestrial areas versus aquatic/regularly flded; Artificiality f cver and land use. The agreement and applicatin f these classifiers have resulted in a number f generic land cver categries that shuld be cnsidered in future mapping effrts: Trees (further separated by leaf type and leaf lngevity); Shrubs (further separated by leaf type and leaf lngevity); Herbaceus vegetatin (further separated int grasslands and agricultural crps); Bare areas; Built up areas; Snw and/r Ice; Open water. These categries are defined independently f the mapping scale, and any applicatin f a minimum mapping unit will eventually result in mixed unit categries f these generic classes, i.e. thrugh specifying cver percentages fr the mapping units. Figure 6 illustrates the cncept f mving frm a terminlgy standard, t a thematic standard, and a cartgraphic standard, thus defining mapping categries frm a cmmn basis and cmmn understanding. The figure als prvides the basic cncept fr the develpment f a legend that allws mapping t be cnsistently categrized UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

30 2.rev.2 22/02/ internatinally, while leaving the pprtunity fr prvisin f additinal categrical detail, e.g., accmmdating reginal specific characteristics r natinal mnitring requirements. This general apprach is suggested fr all peratinal land cver bservatin activities. Instead f mapping categries, the data analysis may be perfrmed at the level f individual classifiers (i.e. tree cver, shrub cver, herbaceus cver, etc.) and can entail specific density threshlds (e.g., tree cver percent) r n a cntinuus range. Figure 6: Cncept f linking and characterizing land cver mapping categries thrugh cmmn classifiers, the definitin f generic classes and the applicatin f a cartgraphic standard (adpted frm (Herld et al. 2009)) In creating requirements fr next generatin earth system and climate mdels, the fllwing key science bdies must be cnsulted accrding t ESA s climate change initiative statement f wrk fr Land Cver CCI (EOP-SE 2009a) : Internatinal Gesphere Bisphere Prgramme (IGBP) is the internatinal research prgram studying glbal change acrss the Earth System. Key prjects with reference t land cver include the Analysis Integratin and Mdeling f the Earth System (AIMES) and the Glbal Land Prject (GLP). Glbal Observatins f Frest and Land Cver Dynamics (GOFC-GOLD) is a prject f the Glbal Terrestrial Observing System (GTOS) prgram. The main gal f GOFC/GOLD is t prvide a frum fr internatinal infrmatin exchange, bservatin and data crdinatin, and a framewrk fr establishing the necessary lng-term mnitring systems (fllw this link fr dcumentatin f the GOFC-GOLD land cver implementatin team) IGOL requirements The Integrated Glbal Observing Strategy (IGOS) is a strategic planning prcess initiated by a partnership f internatinal rganizatins that are cncerned with the bservatinal cmpnent f glbal envirnmental change issues. It links research, lng-term mnitring and peratinal prgrammes, bringing tgether the prducers f glbal bservatins and the users that require them t identify prducts needed, gaps in bservatins, and mechanisms t respnd t the needs f the science and plicy cmmunities. Its principal bjectives are t address hw well user requirements are being satisfied by the existing bservatin systems, and hw they culd be met mre effectively in the future thrugh better integratin and ptimizatin f satellite, airbrne and in situ bservatin systems. The IGOS Land Theme was initially prpsed in Nvember 2003 n the recgnitin that IGOS-P had nt yet cnsidered many bservatinal needs relating t many aspects f the land, such as sustainable ecnmic develpment, natural resurces management, cnservatin and bidiversity. The IGOS UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

31 2.rev.2 22/02/ reprt n land (Twnshend 2008) utlines the bservatinal requirements fr a large range f uses including agriculture, frestry, land degradatin, ecsystem gds and services, bidiversity and cnservatin, human health, water resurce management, disasters, energy, urbanizatin and sustainable human settlements. T satisfy these needs there is cnsiderable verlap in the types f bservatins needed by different users and hence assessment f the needs fr enhanced bservatins is discussed under types f bservatins. Land cver prducts are recgnized by IGOS as having a central rle fr all applicatins. Several bservatin needs and technical requirements are identified in the IGOS reprt. A critical requirement is identified t mve frm research t peratinal mnitring capabilities fr land cver, with peratinal data and prduct suites that are better defined, flexible and penly available. Related implementatin requirements include (Twnshend and Brady 2006): crdinated and cnsistent land cver data acquisitin, bth frm satellite and in situ bservatins; crdinatin f varius internatinal satellite assets fr land cver mnitring at bth mid (similar t Landsat) and mderate reslutin (similar t MODIS); standardized mapping and derivatin land mapping prducts; harmnizatin and synergy f existing land cver maps; rigrus validatin f map prducts using internatinally agreed prcedures; imprved match between data, data prducts and user needs, i.e. ensure adequacy and advcacy t serve internatinal cnventins. Recmmendatins made by IGOS cncerning land cver mnitring are: Develp acquisitin strategies fr land cver data that ptimize cverage in time and space; Minimize interruptin f mid (30-m)-reslutin data; Ensure future cntinuity f Landsat-SPOT-type data deply a remte sensing system designed fr land cver mapping at 1: scale that includes a multispectral scanner with m grund reslutin and SAR with L-band frequency (10 50 m grund reslutin); Crdinate radar and ptical data acquisitin s that radar data can be used fr regular, glbal mnitring f land cver; Agree upn an internatinally accepted land cver classificatin system; Crdinate internatinal cllectin f in situ data fr calibratin and validatin effrts IGCO requirements The verall gal f the Integrated Glbal Carbn Observatin (IGCO) theme is similar t the verall gal f the ECV Land Cver prject: t develp a flexible yet rbust strategy fr deplying glbal systematic bservatins f the carbn cycle ver the next decade. Indeed, the mst successful advances in understanding springs frm the cmbinatin f data and mdels fr the different dmains, wherein results frm ne dmain place valuable cnstraints n the wrkings f the ther dmains. The strategy fr a crdinated system f integrated glbal carbn cycle bservatins (Ciais 2010) is first f all carbn crsscut f GCOS, GTOS, and GOOS (GOOS) and secndly an identificatin f new cmpnents nt previusly identified. The crdinated system f glbal carbn bservatins will be built arund cmplementary cre grups f bservatins t address three themes: fluxes, pls, and prcesses. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

32 2.rev.2 22/02/ Fluxes The first set f bservatins enables quantificatin f the distributin and variability f CO 2 fluxes between the Earth's surface and the atmsphere. As part f this, land cver prducts are needed t create a cmbinatin f satellite bservatins, backed up by a lng-term cntinuity f measurements, delivering glbal bservatins f parameters that are required t estimate surface-atmsphere CO 2 fluxes where direct in situ measurements are scarce. The crucial satellite bservatins that are required fr this are amng thers: land cver status, disturbance extent and intensity, parameters related t vegetatin activity, cean clr. Pls The secnd set f bservatins fcuses upn changes in the key carbn pls, ne f them being frest bimass. Frest bimass inventries are imprtant fr mnitring changes in the abve-grund terrestrial carbn pl size. At present, hwever, these inventries are primarily designed t quantify the vlume f merchantable wd in a given regin with high accuracy (standard errr f 1% at the natinal level). This quantity relates in a predictable manner t carbn stred in tree bimass. Allmetric equatins relating bimass t diameter, height and tree age factrs are needed t cnvert these vlume estimates int whle tree carbn cntent. Using cnstant cnversin/expansin factrs, as is usually dne, results in large errrs, since bth wd density and expansin factrs vary cnsiderably with age and between species. Further, cnversin f vlume increment btained frm repeated inventries int carbn sequestratin needs an extra set f expansin factrs that take int accunt differences in turnver rates f different plant rgans. Much wrk has yet t be dne t create cntinuus, standardized, ge-referenced frest bimass and sil carbn inventries. It is critical t harmnize the widely varying methdlgies fr inventry and analysis, in rder t synthesize carbn estimates based n natinal frest inventries. In additin, a majr bservatinal challenge is t establish allmetric functins cnverting abve-grund bimass t ttal bimass. Further wrk is als needed t expand the cverage ver nn-cmmercial frests and wdlands, ver trpical frests, and t develp satellite technlgy (LIDAR r Radar) fr remte sensing f bimass. SAR data are expected t cntribute t estimating bimass. Hwever, high reslutin bservatin f frest by SAR has been fragmented in terms f tempral and spatial sense, and cnditins f bservatin (incident angle, etc.) are different frm ne satellite t anther. There is a need t build systematic, repetitive, spatially hmgeneus and well crdinated glbal bservatin strategies fr frest mapping by high reslutin SAR. Prcesses The third set f bservatins in the system is measurements related t imprtant carbn cycle prcesses. Mst f these will remain in the research dmain, t be crdinated within the framewrk f the Glbal Carbn Prject. Tw prcess-related bservatins, hwever, are mre apprpriate fr the peratinal dmain and will becme part f the cre set f the system. These can be mnitred by using land cver prducts. Fire distributin (ht spts) and burned area extent, t estimate the fluxes f carbn that are emitted during fires. Fire ht spts will be measured n (sub) daily time steps, with fire extent at mnthly intervals. Land-cver change, t estimate the fluxes f carbn assciated with frest clearing and reversin f agricultural lands t natural ecsystems. The sampling interval will be 5 years with a spatial reslutin f 1 km. The challenge here is t emply in an peratinal mde satellite systems t mnitr land cver changes (5-year time interval, 1 km spatial reslutin), fire ht spts (daily reslutin) and burned UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

33 2.rev.2 22/02/ areas (mnthly reslutin) The land-cver change bservatins shuld als emphasize frest/nnfrest transitins at higher spatial reslutin (25 m). The ultimate gal f the crdinated system f glbal carbn bservatins is t generate data prducts that are f value fr the user cmmunities. Raw bservatins are rarely adequate n their wn. T create usable prducts, in situ measurements frm a variety f surces need t be integrated with remte-sensing bservatins within a mdeling framewrk. T achieve this, a majr challenge is t cllect, prcess and harmnize in situ data frm diverse surces. At present prblems with in situ data include, amng thers, incnsistent parameter definitins, incmplete data, differing spatial and tempral scales and sampling bias in measurements Results f brader user assessment The brad user survey aimed at btaining user requirements cming nt directly frm climate mdelers but the climate cncerned users such as thse making use f land cver infrmatin fr ther scietal benefits r natinal reprting and accunting. This grup represents the brad land cver data user cmmunity. The brad user survey cnsisted f 12 clsed questins and was nline fr a perid f 21 days (24 th Sept t 15 th Oct. 2010). The survey can be fund in Appendix A. The user survey was send t the list f registered GlbCver users with mre than 8000 addresses. This grup is perhaps currently the mst active glbal land cver user cmmunity and quite suitable fr brder user requirements since the Land Cver CCI activities are building upn the GlbCver heritage. The ttal number f answered surveys was 372, frm which 79 were nly partially answered. These partially cmpleted surveys are nly included in the results fr the cmpleted answers. In Figure 7, the gegraphic distributin f the respndents t the survey is presented. The majrity (48%) f the respndents is wrking in a University/ Research institute, and 21% is wrking in the cmmercial sectr (Figure 8) Respndents (%) Eurpe Nrth America Asia Suth America Africa Australia 0 Figure 7: Glbal dispersin (per cntinent) f the users that cmpleted the brad user survey UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

34 2.rev.2 22/02/ % 14% 21% 48% University / Research institute Nn-Gvernental rganizatin Cmmercial sectr Gvernmental /Internatinal rganizatin Figure 8: Type f emplying institutin f the respndents The applicatins where the respndents use the GlbCver prduct fr are mstly in the field f natural resurces (28%) and Infrmatin technlgy/gis (27%) fllwed by Remte Sensing (19%), Climate/ Meterlgy/ Hydrlgy (16%), and Cartgraphy (10%). In general, the majrity f the respndents (70 %) indicate that the required spatial reslutin f the land cver prducts shuld be smaller than 300 m (Figure 9). Fr 20% f the respndents the current glbal standard spatial reslutin ( m) wuld be sufficient. When lking at the applicatin type, climate users tend t prefer a carser spatial reslutin while users wrking in the field f natural resurces prefer a mre detailed reslutin. 100% 80% 60% 40% 20% > 1 km m < 300 m 0% Cart. Climate GIS Nat.Res. Rem.Sens. Figure 9: Preference fr spatial reslutin f land cver data per applicatin type UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

35 2.rev.2 22/02/ % 80% 60% 40% Every 10 years Every 5 years Yearly 20% 0% Cart. Climate GIS Nat.Res. Rem.Sens. Figure 10: Update frequency required fr land cver prducts per applicatin type On the questin in what frequency updated versins f land cver prducts shuld be available, 70% f the respndents replied that a yearly update wuld be sufficient, while 27% f the respndents replied that a prduct every 5 years wuld be sufficient and nly 8% f the respndents requires an update every 10 years (Figure 10). Users frm the natural resurces field prefer a less regular update frequency cmpared t the ther applicatins fields. With regard t defining classificatin requirements, the questin was asked which land cver classes are mst imprtant fr the applicatin case f the respndent. Frm the results (Figure 11) it can be seen that mst respndents are interested in all classes with n particular emphasis, while the tree classes are mst imprtant as an individual land cver class fllwed by agriculture, urban and wetlands. % times mentined All n particular interest Tree classes Shrub classes Herbaceus classes Barren land classes Agricultural classes Urban classes Wetland classes Other specific classes Figure 11: Imprtance f land cver classes fr the respndents applicatin field UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

36 2.rev.2 22/02/ % 23% 9% 52% Frest changes Urban sprawl Agriculture intensificatin Desertificatin Figure 12: Land change dynamics in which brad users are mst interested In the field f land dynamics mnitring, the respndents are mst interested in frest change mnitring (52% f the respndents), fllwed by urbanizatin and urban sprawl(23%). Accrding t 91% f the respndents, the Land Cver Classificatin System (LCCS) is suitable t use fr land cver classificatin. Of thse respndents wh disagreed with the use f LCCS as classificatin system, sme f them suggested t use a classificatin based n the Crine Land Cver prduct. Cmments n the use f LCCS were mainly n the (fuzzy) way in which the classes are defined, and a need fr greater sensitivity t different vegetatin classes in the LCCS. Cncerning the questin n the preferred technique fr dwnlading and the preferred file frmats in which the land cver prducts shuld be available in the (near) future, the use f FTP servers in cmbinatin with GEOTIFF file frmats r HTTP servers in cmbinatin with GEOTIFF frmats was given as the preferred data access and delivery methd (mre than 90% f replies). Trrent servers and HDF-EOS, and NetCDF file frmats are significantly less ppular t use fr data access and delivery Assessment f Climate mdelling cmmunity requirements The key user cnsultatin fr the prduct specificatins includes the partners and prcesses directly invlved r assciated with ESA thrugh CMUG and being partner in the Land Cver CCI prject. They are the Max Planck Institute fr Meterlgy (MPI-M), the Labratire des Sciences du Climat et de l Envirnnment (LSCE) and the Meterlgical Office Hadley Center (MOHC). The bjective f this key user cnsultatin was t prvide detailed requirements n land cver data characterizatin as defined by the key users f the prject. This is dne by (1) actively engaging in the CMUG prcess (2) rganizing and implementing a key user interactin and prduct specificatin meeting t finalize the Land Cver CCI prduct characteristics as dialg amng users (implemented primarily thrugh meetings) and prducers and (3) cnducting a detailed user survey n the specific requirements fr land cver data characteristics t be used in the key and assciate user mdels (spatial, tempral, thematic detail, accuracy requirements) CMUG requirements ESA has established the "Climate Mdeling User Grup" (CMUG), t place a climate system perspective at the centre f the CCI prgram, and t prvide a dedicated frum thrugh which the EO Data Cmmunity and Climate Mdeling Cmmunity can wrk clsely tgether (see als CMUG 2010). CMUG cnsists f the different grups, being MOHC, MPI-M, ECMWF, MétéFrance. In a recent climate requirement baseline dcument (CMUG 2010), CMUG states that glbal land cver and land cver dynamics is an imprtant variable fr glbal and reginal climate mdeling ver many time scales. Land cver infrmatin is used in climate mdels fr the initializatin as well as a bundary cnditin. The land cver infrmatin is hereby translated int surface parameters (e.g., UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

37 2.rev.2 22/02/ albed, LAI, fractinal vegetatin cver) which prvide the lwer bundary cnditin fr the atmspheric mdels. Besides this, detailed reginal land cver infrmatin prvides very valuable infrmatin fr prcess studies like e.g. the assessment f the impact f fires. Fr land cver mnitring, CMUG defined several requirements fr future land cver prducts. CMUG recmmends that despite the fact that land cver data prvides essential spatial patterns f different land cver types, land cver classes have t be translated int mdel relevant surface parameters that can be used in the mdel equatins. Cncerning the translatin f land cver data int mdel parameters, it is recmmends t make use f literature data (Hagemann 2002) r remte sensing based climatlgies like ECOCLIMAP (Champeaux et al. 2005). These methds and cnceptual framewrks are accrding t research dne by CMUG (CMUG 2010) used by mst climate and earth system mdelers. Furthermre, GMUG expresses the need t have a land cver prduct that is cnsistent with surface parameters datasets and needs t match albed, fapar, etc. and vice-versa. A variety f different glbal land cver prducts already exist (e.g. GLOBCOVER, MODIS) fr limited time perids, but these prducts lack cnsistency in time. Table 4: Requirements fr satellite land cver parameters derived frm CMUG user assessment reprt (CMUG 2010) CMUG als recmmends cmbining land cver infrmatin with bserved variability f land surface characteristics which wuld be essential t imprve the descriptin f land surface dynamics in climate mdels. While methds have been develped t retrieve cnsistent land surface parameters frm satellite data these have nt yet been cmbined with high reslutin land cver infrmatin t generate a cnsistent, remte sensing based, land surface parameter data set which can be used as a bundary cnditin in climate mdels. The CMUG requirements fr satellite based land cver mnitring are given in Table 4 (CMUG 2010). Cmpared t GCOS requirements, the CMUG figures are very similar in all respects (Table 5). The Land cver CCI shuld aim at delivering a prduct meeting these requirements with a pssible extensin f the apprach t lnger timescales and an apprpriate errr characterizatin. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

38 2.rev.2 22/02/ Table 5: Cmparisn f GCOS (GCOS-107, WMO database), CMUG (CMUG 2010), and CCI requirements (Surce: CCI prject meetings) Results f key user survey The key user survey was perfrmed during September and Octber 2010, and cnsisted f 27 questins (mstly pen questins). Six key-users frm three rganizatins representing 4 climate mdels were cnsulated fr this survey. All three rganizatins (Max Planck Institute fr Meterlgy (MPI-M), the Labratire des Sciences du Climat et de l Envirnnment (LSCE) and the Meterlgical Office Hadley Center (MOHC)) are als participating in the Climate Mdelling User Grup (CMUG) f ESA CCI. The answers t the questins were divided in answers n land cver prduct requirements fr three different time-frames: (a) current status/used in current mdels, (b) requirements as needed t imprve current mdeling practices, and (c) requirements needed in 5 years time, als cnsidering new mdeling appraches. Accrding t agreements made during land the Cver CCI kick-ff meeting and t reflect the CMUG need that land cver data have different types f uses fr climate mdeling, the survey was divided in 4 different themes: (1) General land cver requirements fr climate mdeling, (2) Land cver as prxy fr land surface parameters (3) Land cver as prxy fr human activities, and (4) Land cver fr validatin f mdel utcmes. Specific questins were frmulated t assess the requirements fr all these elements. The cmplete key user survey is presented in Appendix C. Frm the survey results it can be cncluded that the key users that were cnsulted have a brad interest in earth system/ climate mdeling and thereby represent t a brad extend the climate / earth system mdeling cmmunity. Their main interest is in carbn (stck) mdeling, vegetatin mdeling, plantsil-carbn mdeling, nutrient-cycling mdeling and cupled earth system mdeling (e.g. atmspherecean-bisphere mdeling). The mst ppular land cver prducts and data that are currently used r have been used by the key users are develped in the time-frame (Figure.13) but als lder prducts are still cmmnly applied. The mst frequently used dataset is the IGBP Discver and GLCC as prvided by USGS. Hwever, fr mst mdel applicatin a cmbinatin f land cver datasets is adpted. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

39 2.rev.2 22/02/ # times dataset was mentined by key users < varius timeframe Figure 13: Time frame f the land cver prducts that are used r have been used by the key-users UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

40 2.rev.2 22/02/ ,000 10,000 g ) (l ] 1,000 [m 38,250 10,000 19, , ,000 10,000 1,000 24,000 12,000 1,000 1,000 1, ,000 10,000 1,000 68,750 1,000 10, , reslutin used in current mdels reslutin required t imprve current mdels with reslutin required in new mdeling appraches 10 reslutin used in current mdels reslutin required t imprve current mdels with reslutin required in new mdeling appraches 10 reslutin used in current mdels reslutin required t imprve current mdels with reslutin required in new mdeling appraches Figure 14: Spatial reslutin currently used, required t imprve current mdels with, and required in new mdeling appraches fr: (left) general mdeling practices, (middle) parameter estimatin, (right) land cver and land use change detectin UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

41 2.rev.2 22/02/ Years reslutin used in current mdels reslutin required reslutin required t imprve current in new mdeling mdels with appraches reslutin used in current mdels reslutin required t imprve current mdels with 0.1 reslutin required in new mdeling appraches reslutin used in current mdels reslutin required reslutin required t imprve current in new mdeling mdels with appraches Figure 15: Tempral reslutin currently used, required t imprve current mdels with, and required in new mdeling appraches fr: (left) general mdeling practices, (middle) parameter estimatin, (right) land cver and land use change detectin UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

42 2.rev.2 22/02/ The cnsistency f the current land cver data with the key-users mdel requirements received a varying rating ranging frm sufficient t rather insufficient. Fr example, the matching-up f datasets created in different perids accrding t different classificatins is described as a prblem cncerning the cnsistency f current land cver data with the key-users mdel requirements. Linked t these difficulties cncerning land cver prduct classificatins, the main reasn f interperability prblems is identified in different definitins being used fr key-attributes in datasets and mdels. Als differences in spatial and tempral reslutin are regarded as reasns fr interperability prblems. Furthermre, the allcatin f mdel parameters and the transfrmatin f land cver data t ther infrmatin, due t interplatin issues, remains a surce f inaccuracy. Regarding classificatin, a majr issue is that the assignment f a given bime t a certain Plant Functinal Type (PFT) is nt at all straightfrward. Even if fr example the Olsn classificatin (1994a, 1994b) is used this remains an issue since cmmn PFT types are nt directly represented in land cver prducts, especially with regard t crps (C3, C4), grasses (C3,C4) and wetlands. Due t these classificatin and reslutin (tempral and spatial) prblems, difficulties and inaccuracies arise in attempts t create cmbined datasets fr running climate mdels if datasets fr the histric perid and present day situatin are cmbined used as mdel input fr studies n future scenari s. The accuracy f the land cver prduct fr cntinental/ reginal scale mdeling is regarded as pr, fr the glbal scale mdeling it is regarded as mderately sufficient. Fr ne user where mdels are applied t different spatial extends, the accuracy f the land cver prducts is rated very gd t mderate. Ging frm current t future mdel requirements, a trend twards an increase in required spatial reslutin f land cver datasets can be identified (Figure 14). Hwever, the magnitude f the spatial reslutin required differs fr mdels at different scales. Fr example fr glbal applicatins, future requirements fr spatial reslutins f 1 km were mainly mentined in agreement with currently available glbal datasets. Hwever, fr specific lcal t reginal applicatins, spatial reslutins up t 30 m were mentined. Higher demands are als put n the tempral requirements f land cver prducts ver the cming 5 years (Figure 15). Fr current mdels including imprvements there is a general agreement n a yearly update with a detailing in seasnality. Hwever, the intrductin f new mdeling appraches will require tempral frequencies fr sme classes up t a mnthly reslutin. Furthermre, in rder t imprve current mdels and feed imprved mdel appraches within 5 years, higher demands are put n the tempral ranges available f input data. Fr sme glbal mdels, tempral ranges up t years will be required. T prduce accurate mdel utput with relatively shrt simulatin steps, histrical data f high quality (spatial and tempral reslutin) is required. This sets the requirement fr land cver data t year histrical data fr glbal mdeling purpses and yearly t half yearly data fr mdeling where crp rtatins are taken int accunt. The key users each have their wn apprach in translating land cver classes t plant functinal types (PFTs) and vise versa. In sme mdels, the Olsn majr ecsystem types (1994a, 1994b) are indirectly being used fr defining PFTs as the land surface parameters are based n their distributin frm the assciated USGB dataset. In Figure 16, relative imprtance n which PFTs are used fr land cver classificatin is displayed, and which PFT classes need t be incrprated and extended in future mdeling appraches. Sme key users pinted ut that within 5 years time classificatin schemes must be created that can deal with wetlands and especially with permafrst classificatin. Besides the use f land cver prducts t estimate the ttal area under a certain PFT, land cver prduct can als be used t determine land surface parameters. Examples f these land surface parameters mentined by the key-users are: Albed (surface, vegetatin, snw), Vegetatin rughness, vegetatin fractins, Leaf Area Index, ttal sil water hlding capacity, canpy height. In case the key-users use and/ r require multi-tempral land cver data fr parameter estimatins, the preferred frequency f land cver prduct updates wuld be mnthly t seasnally. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

43 2.rev.2 22/02/ plant functinal types currently used fr land cver classificatin plant functinal types required fr land cver classificatin within 5 years (further develpment) Relative imprtance C3/ C4 Management C3/C4 Crp Types Leaf type Lngevity Leaf type Lngevity Grassland Agricultural crps varius permafrst varius irrigated Trees Shrubs Herbaceus vegetatin Built up areas Snw and/ r ice Open water Bare areas Wetlands Land management practices Figure 16: Relative imprtance are displayed n which PFTs are used fr land cver classificatin (accrding LCCS, Di Gregri, 2005), and which PFT classes need t be incrprated and extended in future mdeling appraches UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

44 2.rev.2 22/02/ With regard t the mnitring f land dynamics triggered by human activities, the main interest lies in the tpic f cnversins between different land cver types resulting in e.g. urbanizatin, defrestatin. Furthermre the interest f the key-users in human induced land dynamics lies in the field f specific agricultural land management practices and crp rtatins, anthrpgenic fire activities and land management practices as irrigatin. A trend twards an increased frequency f available land cver prducts required fr tracking human activities and land use change bservatins cnsidering the frequency currently available, expected t be required t imprve current mdeling practices and the reslutin needed in 5 years when new mdeling practice are cnsidered can be seen in fig. 15 (right). The thematic infrmatin that is f mst imprtance fr describing human activities and disturbances are currently classes describing different land use types fcusing n crp types (C3, C4) and grassland. Fr future mdeling practices n defining human activities and land cver dynamics, the fllwing land cver classes will becme imprtant : crp and pasture/ grassland varieties (C3, C4), irrigated areas, frest, urban areas, specific agricultural land management practices and fire activity. In Table 6 the mdel parameters are represented that are (expected t be) validated using land cver prducts and related bservatinal data. Fr each f the abve mentined parameters that wuld be validated using land cver data (Table 6) mre specific infrmatin is prvided n the level f detail required f the land cver prduct (Table 7). Table 6: Mdel parameters t be validated using land cver prducts and related bservatin data. In bld the parameters are given that are mentined mst Mdel scale Validated using current mdels Glbal Surface albed, Rughness length, Vegetatin rati, Leaf area index, Frest rati, wetland and lake fractin, FAPAR, NPP Validated using imprved versins f current mdels within 1 year Expected t be validated after 5 years after applying new mdeling appraches Reginal Radiatin balance, Energy balance Glbal, Reginal, Cuntry, Lcal Surface albed LAI, FAPAR Bimass abvegrund Surface albed LAI, FAPAR Bimass Burned area Canpy structure (height, density) Biphysical leaf prperties Glbal, Reginal, Cuntry, Lcal Majr land cver types (PFTs represented by mdel) Albed, Leaf area index, canpy height Majr land cver types (PFTs represented by mdel) Albed, Leaf area index, canpy height Perhaps Leaf area index, NPP, canpy height, albed, rughness length, age classes UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

45 2.rev.2 22/02/ Table 7: The level f detail required t validate mdel parameters by means f land cver prducts Mdel scale Parameter Infrmatin need frm land cver bservatins Glbal Surface albed, Rughness length, Vegetatin rati, Leaf area index, Wetland and lake fractin Definitins shuld match thse used in the mdel. Spatial extend (i.e. lcal, natinal, glbal) Spatial reslutin (30 m, 1 km, 1 deg.) Tempral reslutin (hurly, daily, mnthly, yearly) Glbal 0.1 deg. Mnthly Glbal, Reginal, Cuntry, Lcal Frest rati, Sil water hlding capacity Definitins shuld match thse used in the mdel. Glbal 0.1 deg. Annual Albed glbal 1km daily LAI/fAPAR glbal 1km 10 days bimass glbal 1km yearly Burned area Glbal 1km weakly Glbal, Reginal, Cuntry, Lcal PFT cverage LAI NPP Canpy height PFT cverage fr each cell Mdel dependent glbal and reginal. Mdel dependent frm 1-2 degrees (glbal) t 1km (land surface mdel) Yearly mnthly t Besides land cver datasets, ther datasets can be f great imprtance fr mdeling practices. These datasets shuld be cnsistent with land cver datasets. The mst imprtant datasets fr mdeling practices except frm land cver prducts were: Digital elevatin mdel; Water use; Sil data; Grundwater heights; Snw cver; Glacier and ice caps (extent); Fractin f absrbed phtsynthetically active radiatin (FaPaR); Bimass; Leaf area index (LAI); Fire disturbance and Sil misture data. Als, mre infrmatin n the character f the urban landscape is required. Cncerning data access and data delivery, all respnding key users agreed n the latitude/ lngitude system as preferred cartgraphic reference system f land cver prducts. Als the data frmat that is mst cnvenient fr land cver prducts was suggested unifrmly as NetCDF. Fr land cver data delivery, the mst ppular delivery methd is identified as the FTP server r a cmbinatin f web services and a FTP server. The current data retrieval prcess f input data is regarded as easy t mderately easy, hwever, it is als nted that this is very data dependent. The current mst imprtant UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

46 2.rev.2 22/02/ limitatin in the retrieval prcess is defined as the lack f transparency regarding the creatin f the land cver prduct, the degree f quality and reliability f the land cver prduct and the ease with which histrical data can be accessed Analysis f mdel parameters versus land cver The relatinship between land cver types and mdel parameters is ne f the mst imprtant issues determining the accuracy and relevancy f land cver data fr parameterizatin, calibratin and validatin f climate-related mdels. As described in the previus sectins, land cver data are cmmnly used t cnsistently estimate quantitative land surface parameters. The CMUG user requirements dcument (CMUG 2010) addresses this issue and mentins the wrk f Hagemann (2002) as ne basis t prvide a better quantitative understanding why and n what level f detail and accuracy climate users require thematic land cver infrmatin. In Hagemann (2002) a series f nine land surface parameters are derived frm the Olssn land and ecsystem map (1994a, 1994b) using literature data and expert analysis. The fllwing parameters are specified fr 75 different land surface classes: backgrund surface albed surface rughness length due t vegetatin (m) fractinal vegetatin cver (grwing seasn) fractinal vegetatin cver (drmancy seasn) leaf area index (grwing seasn) leaf area index (drmancy seasn) frest rati plant-available water hlding capacity (mm) ttal sil water hlding capacity (vlumetric wilting pint) We used these data t analyze the relative imprtance f different land cver classes fr estimating mdel parameters. The imprtance f each differentiating tw land cver classes is reflected in the relative similarity fr each actual land surface parameter value. Thus, fr each pair f classes (x, y) the similarity ( Sim xy ) can be calculated by relating the specific parameter values fr each class ( Par x, Pary ) t the verall range f parameter values acrss all classes ( Par max Par min ): Parx Pary Simxy = Par max Par min The similarity value is reprted in percent with 100% representing the same parameter value fr this pair f classes. The result is a symmetric matrix f 75x75 classes fr each f the nine surface parameters. These large matrices cntain imprtant infrmatin but will be presented here as selected and aggregate results. Figure 17 shws the histgrams f the distributin f the similarities amng all class pairs fr fur parameters. Fr different land surface parameters the pattern f class similarity is rather different. Fr Albed, there are a few classes that bviusly have a very different value (Snw, ice, water) than many f the ther classes that are relatively similar. Fr the frest rati, there is mre f an equal distributin amng the range f similarity values. An even different distributin is indicted fr UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

47 2.rev.2 22/02/ vegetatin surface rughness and the LAI. This highlights that the relative imprtance and thus accuracy f land cver categries fr mdel parameterizatin varies depending n what mdel parameter is estimated frm the data. A single verall accuracy fr a land cver map value will nt be able t prvide the infrmatin n hw accurate a specific map is fr parameter estimatin. Figure 17: Histgram f similarity values (in percent, x-axis) representing the relative difference in values amng 2 land cver classes fr fur land surface parameters. Nte: the scale f y-scale vary fr different diagrams Figure 18 further shws that specific classes have different relative imprtance as fr the case f Albed. The Olssn map prvides a series f categries with mre r less cnsistent thematic definitin drawing frm land cver and vegetatin types, climatic cnditins, different levels f mixed classes and thers. T prvide sme infrmatin we have gruped the classes int majr land cver categries used fr previus glbal land cver cmparisn studies and smewhat reflecting the GTOS requirements fr land cver (Herld 2008). Table 8 shws the average similarity frm 9 parameter values fr 12 land cver classes aggregated frm 75 Olssn map classes. The areas with pink table cells have the highest average similarities amng all land surface parameters. There is a tendency that they are lcated near the diagnal f the matrix reflecting smewhat the ranking f classes 1-12 frm Frests t barren and water areas. Mst dissimilar are the nn-vegetated and vegetatin classes. A misclassificatin and cnfusin between tw classes with large similarity will cause a much lwer errr in the quantitative parameter estimatin than uncertainties amng very dissimilar classes. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

48 2.rev.2 22/02/ Table 8: Matrix f the similarity between the 12 generalized land cver classes as average fr 9 land surface mdel parameters Generalized Land Cver Legend Evergreen Needleleaf Trees Evergreen Bradleaf Trees Deciduus Needleleaf Trees Deciduus Bradleaf Trees Mixed/Other Trees Shrubs Herbaceus Vegetatin Cultivated and Managed Veg. Urban/Built-up Snw and Ice Barren Open Water 1 Evergreen Needleleaf Trees 2 Evergreen Bradleaf Trees Deciduus Needleleaf Trees Deciduus Bradleaf Trees Mixed/Other Trees Shrubs Herbaceus Vegetatin Cultivated and Managed Veg Urban/Built-up Snw and Ice Barren Open Water Results f assciated user survey A grup f 85 users frm the climate mdeling cmmunity was apprached t fill in an nline survey n their user requirements fr current and future land use data requirements. The survey was perfrmed in Octber 2010, and cnsisted f 16 questins (Appendix B). Fr a selectin f the questins, land cver prduct requirements fr tw time perids needed t be selected: (1) current status/used in current mdels, and (2) requirements needed in 5 years time, als cnsidering new mdeling appraches. In additin, land cver requirements were assessed fr fur different climate mdel aspects as presented in sectin fr the key user assessment: (1) land cver requirements, (2) land cver as prxy fr land surface parameters (3) land cver as prxy fr human activities, and (4) land cver fr validatin f mdel utcmes. Selectin f the grup f s-called assciated users was based their rle as being main develpers fr a certain type f climate r earth system mdel (Appendix D). Frm the ppulatin f 85 users, 15 filled in the questinnaire resulting in a respnse rate t the assciate survey f 18% frm a brad range f cuntries all ver the glbe. The results f the assciate user survey shw that land cver data are applied fr a brad range f climate mdeling applicatins (Figure 18). Respndents were mstly applying their mdels at glbal scale (53%) r natinal scale (27%). A brad set f different available land cver datasets are used where the mst frequently mentined are the IGBP Discver and GLCC datasets as prvided by USGS and FAO statistics (Figure 19). UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

49 2.rev.2 22/02/ Cunt (%) Glbal circulatin mdeling Dynamic vegetatin mdeling Carbn (stck) mdeling Land use/cver (change) mdeling Ecsystem mdeling Land surface mdeling Plant-sil-carbn mdeling Nutrient-cycling mdeling Cupled earth system mdeling Impact assessment mdeling Figure 18: Earth system r climate mdeling fcus f respndents t assciate user survey Cunt (%) IGBP and GLCC MODIS land cver GLC2000 MODIS VCF CORINE NLCD TERRASTAT SYNMAP GLOBCOVER ecsystems Olsn HYDE Ramankutty and Fley Natinal database FAO statistics In situ Other Figure 19: Land cver prducts used in assciate climate mdeling cmmunity The results als shw that in many cases land cver datasets fr different cverage perids are cmbined t derive a time-series f land cver develpment. In general, the accuracy f the land cver prduct fr climate mdel applicatin is judged as mderate till gd. The main prblems which are mentined are the Access and knwledge t updated land cver datasets (40%), difficulties with data UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

50 2.rev.2 22/02/ aggregatin, cnsistency fr the allcatin f mdel parameters, lw tempral reslutin and tempral range f input data and lw spatial reslutin and spatial extend f input data (all 27%) (Figure 20). Cunt(%) Transfrmatin LC t surface infrmatin Cnsistency allcatin f mdel parameters Difficulties with data aggregatin Difficulties with data interplatin Lw tempral reslutin/range PFTS nt sufficiently represented Lw spatial reslutin/extent Different definitins key-attributes Thematic accuracy f LC datasets Access/ntificatin updated LC datasets Other prblems in use Figure 20: Identified prblems when using available land cver data sets fr climate mdeling applicatins The user requirements fr the spatial reslutin reflect mre r less the mdel applicatin at glbal and natinal scale with preferred grid size f 100m and 0.5 degrees respectively (Figure 21). Lking at requirements fr climate mdeling applicatin in 5 years, the results shw that a mre detailed spatial reslutin is required but still the glbal mdel applicatins will use reslutins between 0.25 and 0.5 degrees. Tempral reslutin requirements fr current mdel applicatin are mainly n a yearly basis with sme preference fr high-frequency data up till daily but and fr glbal applicatins with an update frequency frm 5 till 10 years (Figure 22). Hwever, there is a clear future need fr mre seasnal prducts with a quarterly till half year tempral reslutin which wuld be able t track the seasnality f agricultural crps and frest ecsystems. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

51 2.rev.2 22/02/ current mdel in 5 years cunt (%) m, m m m 500m-1km, 1-5km, >5 km < 0.25 degrees degrees spatial reslutin degrees 1-5 degrees 5-10 degrees 10 degrees natinal aggregates Figure 21: Spatial reslutin requirements fr current climate mdel applicatin and expected in 5 years current mdel in 5 years cunt (%) Daily r finer Mnthly - Quarterly Quarterly - 6 mnths 6 mnths- 1 year, 2 years 5 years 10 years 50 years Mre than 50 years tempral reslutin Figure 22: Tempral reslutin requirements fr current climate mdel applicatin and expected in 5 years User requirements fr the thematic aspect f land cver datasets indicate that agricultural classes are very imprtant while als fr current mdeling applicatins natural vegetatin classes (frest and herbaceus) are seen as imprtant (Figure 23). Hwever, fr future mdeling applicatin it is anticipated that a prper representatin f urban and wetland classes will becme mre relevant. This agrees with the results f the key-user survey. When lking mre specific at infrmatin requirements n human activities/disturbances r dynamics (Figure 24), the utcme f the survey shws that currently frest lss, agricultural expansin and vegetatin phenlgy are imprtant prcesses which are taking int accunt in the initializatin r evaluatin step f the climate mdels. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

52 2.rev.2 22/02/ Fr the next generatin mdels, aspects wetland dynamics, urban expansin and lng-term vegetatin develpment will becme imprtant prcesses t take int accunt. Cunt(%) Tree cver/frest current mdel in 5 years Shrub classes Herbaceus classes Mixed vegetatin Barren land classes Agricultural classes Urban classes Wetland classes Figure 23: Mst imprtant land cver classes fr current climate mdel applicatin and expected in 5 years Cunt(%) current mdel in 5 years Nne Frest lss Urban expansin Agricultural expansin Vegetatin phenlgy Snw phenlgy Fire/burned area Wetland dynamics Land degradatin Lng-term vegetatin Other Figure 24: Mst relevant human activities/disturbances r dynamics fr current climate mdel applicatin and expected in 5 years Within the mdeling prcess, land cver prducts are als adpted t determine land surface parameters which are then use t initialize the climate mdels. Figure 25 gives an verview f land surface mdels which are derived frm land cver data. Fr example, Leaf Area Index (LAI) is ne parameter that is regularly derived frm land cver datasets. Althugh several ther parameters are already derived frm land use data, it is anticipated that especially future climate mdeling appraches will increasingly apply this mechanism fr parameters like vegetatin albed, vegetatin rughness and plant water hlding capacity. Finally, the applicatin f land cver data t validate climate mdel utput was assessed (Figure 26). Currently this is mainly applied fr the vegetatin distributin and UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

53 2.rev.2 22/02/ dynamics and the radiatin and energy balance. Fr future mdeling applicatins, land cver data will increasingly be adpted t validate net primary prductin (NPP), albed and LAI. Cunt(%) current mdel in 5 years 10 0 Nne Backgrund albed Sil albed Vegetatin albed Vegetatin rughness Vegetatin rati Leaf area index Frest rati Sil WHC Plant WHC Vlumetric wilting pint Sil type/texture Other Figure 25: Land surface parameters used in climate mdels which are estimated frm the land cver data 70 Cunt(%) current mdel in 5 years 10 0 Nne Radiatin balance Energy Balance NPP LAI Albed Vegetatin distributin Vegetatin dynamics Area f ice sheets Area under permafrst Other Figure 26: Output parameters f climate mdels which are r will be validated using land cver data Cncerning data access and delivery, 50% f the users prefer latitude/lngitude as cartgraphic reference system while in additin a brad range f ther systems were mentined: UTM (Albers), equidistant (Lambert Azimuthal), Transverse Mercatr. As mst cnvenient data frmats fr delivery were mentined NetCDF (50% f users) and GeTIFF (45% f users). Fr data delivery, FTP (50%) and the cmbinatin f web services and FTP (e.g., request via web service and de-livery thrugh FTP) (42%) were mentined as mst frequent ptins. UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

54 2.rev.2 22/02/ Scientific literature review The brad assessment f existing (climate) mdels and accmpanying user requirements aims at examining hw land cver data have been used in climate mdels and which future needs can be identified fr mdeling practices. Belw, the results frm a standard literature review f key scientific papers published primarily since 2005 is presented. The perfrmed review fcused n current use f land cver data fr climate mdeling and n the identificatin f future needs, mdel requirements and -prerequisites. Special attentin is paid t highlight innvative cncepts and appraches t better reflect land dynamics in the next generatin mdels. This review includes different mdeling appraches and cmmunities, i.e. Earth System mdeling cmmunity, Integrated Assessment mdeling cmmunity and the Impact, Adaptatin and Vulnerability cmmunity (Hibbard et al. 2010).The identified mdel requirements are presented in shrt term (current) and lng term cnsideratins and visins (future). These specific time-frames were selected t make a divisin between urgent needs and requirements which shuld be put n the shrt term agenda and requirements that are still urgent but less pressing. The results are presented belw and are, where applicable, linked t GCOS tasks fr land cver as defined in the GCOS implementatin plan. Shrt term requirements Standardizatin f land cver prducts with regard t the definitins f classes and their threshlds is an imprtant issue (Jung et al. 2007). This issue is als addressed in the in 2004 defined GCOS Implementatin Plan (IP) task 22, which prmtes the harmnizatin f land cver mnitring by creating internatinal standards fr land cver maps. It is widely acknwledged that land data prducts shuld ideally be prduced by using a hierarchical, standardized land cver classificatin system which shuld be applied t validated land cver data and t time-series f data integrated at an apprpriate scale (Lepers et al. 2005, Hibbard et al. 2010). Land cver prducts ften lack class specific accuracies and categries have large interclass variances (especially fr mixed vegetatin classes) (Jung et al. 2006, Jung et al. 2007). Plant functinal types are ften used as a basis fr class definitin (Olsn 1994a, b), hwever mre research is needed n the effects f wrng categrizatin f plant functinal types n C:N ratis (Ostle et al. 2009). In a mre general sense it is stated that parameters must be used that are bth mechanistically imprtant and measurable (Ostle et al. 2009). This need t validate parameters requires (new) methds fr land cver map accuracy assessments (Williams et al. 2009). Fr example, knwledge abut class specific accuracies f the prduct can, in cnjunctin with calculated fuzzy agreements be used t generate a map f cnfidence f the final prduct (Jung et al. 2007). Despite f such methds, validatin f land cver maps remains an issue as was already addressed in GCOS task 23 (IP 2004). Even if pre-defined land cver classes are used, as in e.g. land cver prducts prvided by the FAO (Di Gregri and Jansen 2000), glbal land cver is ften incnsistent with land cver data and actual practices. Accuracy assessment and errr reductin shuld be imprved (Williams et al. 2009) by btaining land cver reference data since n rigrus validatin is yet pssible. This pint was als raised as part f the 2004 GCOS task 25 develpment f an in situ reference netwrk fr land cver. Mdels need t be mre bviusly cmparable t the real wrld (Friedlingstein et al. 2006) and therefre further mdel evaluatin against site-level measurements are needed. This may increase the reliability f fr example the mdel estimated Eurpean carbn balance in the future (Vetter et al. 2008). Per definitin, it is nt pssible t crrectly interpret carbn cycle simulatins if the verall-, user-, and prducer accuracy is nt knwn (Jung et al. 2007). Special attentin has t be paid t data n land cver change since large uncertainties in tw datasets used fr change detectin can result in extreme values n land dynamics (Jain and Yang 2005). Summarizing, t be able t reduce large uncertainties in carbn and climate mdeling, it is critically imprtant that these mdels are mre cmpletely cnstraint by bservatin data UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

55 2.rev.2 22/02/ (Friedlingstein et al. 2006). Therefre, there is an urgent need fr a netwrk f grund and satellite based lng term land cver mnitring (Jain and Yang 2005). Thereby, the benchmarking f glbal mdels is a key-prcedure and an expanded set f data fr evaluatin f shrt timescale dynamics fr benchmarking is required (Sitch et al. 2005). These datasets can partly be generated by linking ptical remte sensing prducts which prvide critical infrmatin n e.g. canpy structure and crp phenlgy (Williams et al. 2009). Furthermre, the scientific cmmunity suggested t further expand the FLUXNET twer netwrk t btain critical data n carbn exchange (Williams et al. 2009), expansin f the netwrk shuld be initiated n the shrt term and implemented within the cming 5 years. Special attentin shuld be paid n the parameterizatin f albed and the representatin f crp phenlgy and the representatin f evaptranspiratin fr different land cver types (Pitman et al. 2009). Therefre, the in 2004 defined GCOS task 26 which fcuses n the creatin f annual land cver prducts and GCOS task 27 which fcuses n the creatin f a regular fine reslutin land cver (change) map, are still relevant and urgent tasks that shuld be dealt with n the shrt term. Summarizing, n the shrt term different issues shuld be addressed t deal with prblems regarding the definitin f land cver classes; classificatin f land cver data sets; variatin in spatial reslutin f the data surces and variatin in tempral and spatial cverage f data sets. Furthermre, earth system mdel and climate mdel utcmes shuld be validated against reference data, preferably using fine reslutin land cver datasets that can be prvided n a regular basis Lnger term requirements In the previus paragraph, the shrt term requirements fr earth system mdeling and climate mdeling as fund in key-articles are presented. In this paragraph, requirements fr a mre lng term (1-5 year) scpe are discussed. Mre research n mdel- and data fusin is needed: multiple and different types f data, including assciated uncertainties need t be integrated tgether with prir knwledge n mdel parameters and/r initial state variables (Ostle et al. 2009, Williams et al. 2009). Mre effrt shuld be put in generating new infrmatin by cmbining existing data, fr example by linking Eddy Crrelatin twers effectively with atmspheric clumn CO 2 measurements generated by satellites like OCO and GOSAT (Williams et al. 2009). Besides mdel- and data fusin, there is als a need fr an integral visin n the actual (ec)systems that are mdeled. Fr example fr cean carbn cycle mdeling there is a need fr mre cmplete treatments f cean ecsystems, micrnutrient limitatin, and ceanic acidificatin impacts n calcium carbnate cycling (Friedlingstein et al. 2006). T advance scientific understanding and enhance data- and mdel integratin, the earth system mdeling and integrated assessment mdeling cmmunities have t cllabrate clsely with the remte sensing cmmunity (Hibbard et al. 2010).T be able t address questins n hw we have t adapt t, and minimize risks f, climate changes mdelers have t rely heavily n behaviral mdeling f ecnmic and energy systems, which is the fcus f Integrated Assessment Mdels. Regarding the use f land cver prducts as mdel input, sme specific requirements fr land cver change mnitring are addressed in literature. Fr the lcatin f land cver change detectin, land cver shuld be extended t regins that are nt knwn as htspts but where rapid changes may still take place and catch the scientific cmmunity by surprise (Lepers et al. 2005). Furthermre, the imprtance f including land-cver change in frcing scenaris fr future climate change studies shuld be nted. By accunting fr a number f additinal anthrpgenic climate impacts, land cver frcing can be included which will imprve the quality f reginal climate assessments as e.g. IPCC SRES scenaris (Feddema et al. 2005). In additin, it is stated that withut accunting fr histrical land cver changes, bserved atmsphere CO 2 grwth cannt be explained (Brvkin et al. 2004). This implies the need t incrprate histrical land cver change int carbn exchange/ stck mdels. Mre research is required n the effects f land cver change n changes in land-atmsphere exchange in greenhuse gases, reactive trace gases and aersls (Pitman et al. 2009). UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

56 2.rev.2 22/02/ Linked t the requirement fr earth system mdeling t incrprate land cver change, the decline in land suitability due t sil ersin, acidificatin and salinizatin als need t be taken int accunt (Ramankutty et al. 2002). Besides a better understanding f the required mdel inputs, a mre prcess based understanding f earth system and climate mdels is needed. There is a need t critically evaluate the representatin f plant-sil prcesses in glbal mdels (Ostle et al. 2009). Als applied cncepts f carbn-water cycle interactins regarding the representatin f canpy cnductance and sil prcesses need t be revisited (Jung et al. 2007). In general, a greater prcess-based understanding f large-scale plant-drught respnses and interactin with wildfire and land use is needed and shuld be filtered in the next generatin Dynamic Glbal Vegetatin Mdels (Sitch et al. 2005). As a part f btaining mre knwledge n the mdels prcess understanding, mre research shuld be dne n mdel equifinality: where different mdel representatins, thrugh parameters r mdel structures, yield similar effects n mdel utputs, and s can be difficult t distinguish (Williams et al. 2009). Linked t this, mre insight has t be gained n hw the results f Earth System Mdels may impact underlying drivers (e.g., land use change) f Integrated Assessment Mdeling mdels n glbal feedbacks and carbn cycle dynamics (Hibbard et al. 2010).T be able t generate the required insights and infrmatin described abve, data infrastructures and facilities need t be imprved. Fr the shrt term, the implementatin f several GCOS tasks (task 27 and 28 f the in 2010 defined GCOS tasks) will meet this demand. Fr the lnger term, the scientific cmmunity addresses the need t set up strage and cmputing facilities t facilitate the cllectin f all data and prvide a webbased interface fr data exchange (Jung et al. 2006). As cmputatinal pwer, needed fr e.g. millennium scale carbn cycling becmes available sme studies can be repeated at different scales and acrss e.g. a range f different glbal carbn mdels (Pngratz et al. 2010). With regard t the FLUXNET netwrk (used as validatin fr mdeling practices where land cver data is used), it is suggested t imprve data cllecting facilities by nesting Eddy Crrelatin twers within the reginal ftprint f tall twers that sample the CO 2 cncentratin f the planetary bundary layer (Williams et al. 2009). Table 9: Near-term and lng term requirements t imprve earth system mdeling (Hibbard et al. 2010) Fr the lng term (> 5 years), defined requirements are strngly prcess based. Fr example, the rle f nitrgen in earth system mdeling shuld be clarified (Jung et al. 2007). Nitrgen supply frm sil rganic matter is nt knwn accurately and intrduces uncertainty (Ostle et al. 2009). UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

57 2.rev.2 22/02/ Furthermre, ptential (in)direct effects f climate change n land use change and land cver change must be made quantitative. Due t an increase in greenhuse gases the area f land that is cultivable might increase, but yields might decrease. This has t be taken int accunt in the future fr example in a crp prductivity parameter. Als the effects f climate change n sil prperties need t be accunted fr (Ramankutty et al. 2002). Up till nw, the effects f land-cver change n climate has been difficult because different bi- gephysical effects ffset each ther in terms f climate impacts, and, n glbal and annual scales, reginal impacts are ften f ppsite sign and are therefre nt well represented in annual glbal average statistics (Feddema et al. 2005). UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).

58 2.rev.2 22/02/ Synthesis and recmmendatins In this assessment we have implemented a detailed requirements analysis fr a glbal land cver prduct that shuld meet the requirements f GCOS and ther internatinal panels, and the climate user cmmunity. The study interacted with different types f users thrugh different interactin mechanisms (Figure 27). Overall, three user surveys were cmpleted fr the brad, assciated and key users respectively. While the frequency f respnses vary, the amunt and quality f feedback is suitable t derive a gd synthesis n what climate mdeling users need and expect frm a new land cver prduct. In general, there is quite a gd match amng the requirements cming frm different surces and the brader requirements derived frm GCOS, CMUG and ther relevant internatinal panels (sectin 4.1). Figure 27: Cncept f user cmmunities and activities t assess land cver requirements f general land cver user cmmunity and climate mdeling cmmunity 4.1. Need fr land cver in climate mdels In general, land cver has been and remains a fundamental dataset as cnsistent input t climate mdels and fr the integratin f ther data surces. While it is assumed that any new land cver datasets shuld be better than previus nes and imprve climate mdel and assessment perfrmance, there are several ways land cver feed int different climate applicatins. It has been emphasized that there is a need fr bth stable land cver data and a dynamic cmpnent (time-series and changes). Fr the purpse f this survey we cnsidered three main ways land cver bservatins and data are used: 1. As prxy fr a suite f land surface parameters that are assigned based n PFTs UCL-Gematics 2011 This dcument is the prperty f the LAND_COVER_CCI partnership, n part f it shall be reprduced r transmitted withut the express prir written authrisatin f UCL-Gematics (Belgium).