Concept note. A Roadmap for Future Copernicus Service Component for REDD+

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1 DG Joint Research Centre Institute for Environment and Sustainability H03 - FRC Unit Doc V4-24 March 2016 Ref: unregistered doc Concept note A Roadmap for Future Copernicus Service Component for REDD+ 1. Context The introduction of Sentinel-2 high resolution image time series (i.e. with 10 m spatial resolution) will facilitate a significant scale-step in the use of Earth Observation (EO) data in forest mapping and monitoring applications. This expectation is based on 3 major aspects of the Copernicus programme, each of which contrasts markedly with previous EO scenarios: 1. The unprecedented technical quality of the sensors, in each of the radiometric (relevant channels), spatial (resolution and swath-width) and temporal (revisit frequency) sense, 2. The Full, Free and Open data policy /licensing scheme and, 3. The global coverage of land with a guaranteed continuity (> 10 years) of observations. Tropical forest mapping and monitoring is a key application domain for EO due to the need for recurrent and frequent data to produce annual information on forest cover in humid and seasonal domains and regular information on forest disturbance processes. It benefits from long term consistent archives of Landsat imagery for forest area change, for instance in support to various mature and operational applications such as the Global Forest Watch (GFW) platform 1 of the World Resources Institute and the PRODES project 2 of the Brazilian National Space Agency. Previous attempts to integrate high resolution EO imagery into operational forest degradation mapping and monitoring have largely failed due to inadequate technical parameters, high costs and uncertain long term perspective. The EO use in this community is currently mostly limited to Landsat sensors (30 m), with global coverage products and annual frequency. The use of such imagery (~ 30 m) is currently limited to the creation of tree cover percentages or forest / non-forest binary maps, released at yearly intervals 3. Key limitations in the use of Landsat sensors are the mixed nature of the measured signal, and the difficulty in identifying forest cover disturbances. The latter aspect is especially important in areas where small scale processes are significant. The introduction of Sentinel 2 is essential for the generation of the estimation of areas under specific disturbance factors and the separation of forest specific biophysical parameters. The use of forest-specific map layers derived from S2 will become essential time series in inter-annual trend analysis in forest area change, even if it requires a number of years of consistent observations Hansen M. et al. Science 342, (2013)

2 Version 4-24 March Page 2 The Sentinel 2 sensors together with Landsat 8 - will provide a core capacity on which a viable set of globally consistent services in the forestry domain could be based, setting the stage for a number of innovative and challenging applications, and to the redesign of monitoring systems for more accurate monitoring of forest degradation. The introduction of Sentinel 2 will potentially lead to a spread of forest monitoring capacities to national and regional government levels in the next 5 to 10 years, for instance, as an extension or component of National Forest Inventory (NFI) systems. This will require significant capacity building efforts, which should be, as much as possible, directed to anchoring a robust methodological framework. As far as possible, this should lead to standardized forest area estimates and map products at national level, with agreed accuracy and quality, which can be integrated in regional and global application contexts. This approach could, in principle, be developed further to address more specific and local information needs of sub-national entities. These entities may include local government, research institutes, public forest services, NGOs (e.g. conservation organizations) and private actors (e.g. Logging companies). Although Sentinel usage in these cases may be more within the scope of downstream services, dedicated efforts to promote common methodologies and standard products could be defined as a dedicated service module. In this concept paper, we try to outline how a Copernicus service component could be structured in the coming years to accelerate service take up in the tropical forest mapping and monitoring domain. Such a service set-up should maximize the European contributions to international efforts in the UNFCCC realm, seek to capitalize on the mutual benefit arising from the release of service outputs to collaborative third parties, provide new public interest information infrastructures in Europe and complement the existing monitoring instruments related to the implementation of REDD+ activities in tropical countries. 2. Rationale of a Copernicus service component for REDD+ monitoring Based on a pantropical data set of Landsat satellite imagery, annual gross losses in tropical forest cover are estimated at 7.6 million in the 2000s 4. Deforestation results in immediate release of CO 2 emissions originating from the carbon originally stored in the vegetation. Associated carbon losses would represent circa 10% of carbon emissions from fossil fuel combustion and cement production during the last decade. In addition, degradation (i.e. the loss of carbon and ecosystem services in remaining forests, due to harvesting and small scale disturbances) remains difficult to quantify but could add further emissions of the same magnitude as deforestation for some countries. The subsequent regrowth and restoration of forests, or the lack thereof, also remains a major unknown in climate models. Yet it is expected that in the long run, the global sink (of which tropical forest growth is a major component) would compensate all residual emissions in a carbon neutral economy. It is therefore of prime importance to provide better information on forest dynamics to tropical countries (including the least developed of them) and to the international scientific community (e.g. the International Panel on Climate Change). 4 Achard F et al Global Change Biology (2014) 20,

3 Version 4-24 March Page 3 The Conferences of the Parties (COP-16 to COP-21) to the UNFCCC have shaped a framework for policy approaches and positive incentives supporting forest mitigation in developing countries (REDD+): reducing emissions from deforestation, forest degradation, conservation, sustainable management of forests and enhancement of forest carbon stocks. REDD+ has three Phases: (i) readiness; (ii) capacity building and demonstration; and (iii) performance-based payments for actions that should be Measured, Reported and Verified (MRV) at national level. In order to measure the reduction of emissions from deforestation against which performance-based payments would be provided under phase 2 and 3, REDD+ requires developing countries to design: 1) forest reference levels taking into account historical data and national circumstances; 2) robust, flexible, consistent, accurate and transparent national forest monitoring systems (NFMS to measure performance against reference levels and to assess different types of forest in the country, including "natural forest"); 3) information systems on social and environmental safeguards (SIS). Globally this represents $1.5 billion investments each year. In September 2014, at the UN Climate summit, the European Union, many governments, some of the world s biggest companies, and influential civil society and indigenous organizations have confirmed their collective commitment to mobilize "strong, large-scale economic incentives commensurate with the size of the challenge" and (inter alia): At least halve the rate of loss of natural forests globally by 2020 and strive to end natural forest loss by Support and help meet the private-sector goal of eliminating deforestation from the production of agricultural commodities and other economic sectors by Restore 150 million hectares of degraded landscapes and forestlands by 2020 Include ambitious, quantitative forest conservation and restoration targets as part of new international sustainable development goals. Agree in 2015 to reduce emissions from deforestation and forest degradation consistent with the goal of not exceeding 2 C warming. Provide support for the development and implementation of strategies to reduce forest emissions. Strengthen forest governance, transparency and the rule of law, while also empowering communities and recognizing the rights of indigenous peoples, especially those pertaining to their lands and resources. All REDD+ countries and EU Member States are also Parties to the UNCBD (Convention on biodiversity), and recently acknowledged that "existing biodiversity-related national level processes, could support the further integration of biodiversity concerns into REDD+ national strategies or action plans, [and that] remote sensing, can also provide valuable information relevant to biodiversity." The EU Action Plan for FLEGT (Forest Law Enforcement, Governance and Trade) adopted by the Commission in May 2003, sets out a process and a package of measures by which the EC proposes to address the problem of illegal logging and related trade. One of the key measures proposed is a licensing scheme for the prevention of illegal logging and related EU imports. The licensing scheme is implemented as part of the Voluntary Partnership Agreements (VPAs). In the context of each VPA, the EU and partner country agree to monitor the impact of the VPA on governance, livelihoods, trade but also, obviously, state of the forests. Forest-related information should also be made accessible, as part of the transparency measures foreseen in the annexes of the VPA.

4 Version 4-24 March Page 4 3. Technical challenges related to forest monitoring in the context of REDD+ A number of existing operational service activities will allow stimulating early integration of Sentinel data into forest mapping and monitoring applications. Operational use of EO data and services in forest monitoring is most established amongst a number of large international or governmental entities which focus on national and regional forest monitoring, for political or environmental reasons e.g. fight against climate change and forest protection. Moreover technical guidelines on methodological issues relating to the integration of remote-sensing and ground-based observations for estimation of emissions and removals of Greenhouse Gases in forests have been prepared by the global community of earth observation and carbon experts: the GOFC-GOLD REDD sourcebook 5, and the GFOI Methods and Guidance Documentation 6. However only a few countries in the tropics have developed operational forest cover monitoring systems capable to meet REDD+ reporting requirements (e.g. Brazil for the Brazilian Amazon, Mexico, Indonesia and India). In the recent past a number of initiatives (including from EC) have aimed at developing National Forest Monitoring Systems. However a large majority of these monitoring systems is not fully compatible with REDD+ requirements yet. In addition, there are specific challenges associated to these forest monitoring systems: firstly, at national levels there is often a lack of data and of staff sufficiently trained for forest-cover change analysis, and secondly, robust methods to monitor forest degradation and regrowth are still under development. As stated in the GOFC-GOLD REDD sourcebook, measuring forest degradation or forest regrowth and related forest carbon stock changes is more challenging than measuring deforestation since such forest changes are not easily detectable through remote sensing, requiring more frequent and better imagery and processing. In order to address technical challenges arising from REDD+ activities and FLEGT agreements, it is essential for tropical countries to assess and document changes in forests based on reliable and repeatable methods. It is therefore crucial to provide open and free access to satellite data and to strengthen national technical capacities in developing countries to report on REDD+, FLEGT and other forest related policies. 4. REDD+ Copernicus service components Existing or planned activities Imagery from the Sentinel-2 satellite, acquired every 10 to 5 days over the tropical belt, would be needed as soon as a possible for all countries and states/provinces of the three main tropical forest basins in order to help establish national and/or jurisdictional forest reference levels (taking into account historical data) and to develop robust, consistent, accurate and transparent national forest monitoring systems

5 Version 4-24 March Page 5 Sentinel-2 Product Level 2A is a standard level for which a processing tool will be made available through the Copernicus program (on ESA s Sentinel-2 Toolbox) 7. Level-1C products contain applied radiometric and geometric corrections (including ortho-rectification and spatial registration in fixed cartographic geometry). Level-2A products are bottom of atmosphere reflectance in cartographic geometry. The Level-2A product needs currently to be processed by the user side. A higher level of processing of the satellite imagery data (level 3) would be needed for a REDD+. This level 3 should consist into proper image mosaics (minimizing the cloud coverage) from the Sentinel-2 satellite time series, composed every 30 days or every 3 months over the tropical belt. The specifications for a standard Sentinel-2 Level 3 core product to be made systematically and freely available through a free and open distribution platform could be prepared by Copernicus programme in Forest monitoring and mapping application activities can be considered as specializations of the Copernicus Land Service. The hot-spot monitoring activity will be implemented from This activity will be aimed at land use changes affecting biodiversity over selected hot spot areas over the Globe. This activity may also facilitate initial preoperational approaches using S2 at local scale, where forest is a dominant land cover. REDD+ Copernicus service component A clear candidate for a new dedicated Copernicus service component is one that addresses high resolution forest area delineation and disturbance indicators. Such a component should be aimed at automated annual forest map at 10 m resolution with main land cover classes with at least forest / non-forest distinction with accuracy of 85%, potentially including a few forest types, i.e. supporting the assessment of a "natural forests" class, as defined and operationalized by UNFCCC Parties to comply with UNFCCCC Decision 11/CP.19. The introduction of this service component should adopt a phased approach, starting on a selection of representative countries (e.g. 10 countries in 2017) and for several consecutive years (e.g ). The products should have clearly defined minimum accuracy and quality specification. Furthermore, its set-up should accommodate for periodic upgrades in the methodologies, with a capacity to reprocess the time series preceding the methodology update and to extend the generation of consistent products from archived imagery to other areas. Benchmarked against pre-defined performance criteria, the component could then be scaled up to cover a larger selection of tropical countries. The land service should ensure an optimized and easy access (on demand) to such data for partner institutions, depending on specific conditions at national and international levels (satellite dissemination facilities or national space agencies, efficiency of internet connections, agreements with external and international space organizations). The default query should be made simple and standardized as far as possible, e.g. the country/states/provinces to be covered, and the date or period. User support should be made available for more complex queries. The available format of data should be such that it suits the needs of those users. 7

6 Version 4-24 March Page 6 Capacity building (outside Copernicus frame) A separate support to REDD+ countries should be dedicated to capacity building in Sentinel 2 use on a per country basis. This complementary component would adapt methodologies, establish best practice, standardization and quality verification as part of national forest inventory infrastructure in support of national forest assessments. Common forest area products could feed into regional assessments. Such component would include ancillary tools which would be beneficial in the framework of REDD+: Spatial analysis tools for producing a summary table of land cover changes in forest type and natural forest class between two yearly maps.

7 Version 4-24 March Page 7 Annex I: Overview of new capacities of Sentinel 2 and their relevance to tropical forest monitoring Sentinel-2A (S2A) was launched on 23 June 2015 and will provide wide area optical imagery with 10 m (visual and near-infrared), 20 m (red-edge, near and short-ware infrared) and 60 m (visual to shortwave infrared for atmospheric correction) resolutions from October 2015 onwards. The S2A has wide swath width (290 km) and a 10-day revisit frequency. S2A coverage will be global (land masses). Identical B unit of S2 is scheduled for 2017, increasing the revisit capacity to 5 days for S2. The Copernicus programme already foresees C and D versions of these Sentinels to guarantee data availability until, at least 2027 and, provisionally, next generation versions beyond that. Essentially, the ensemble of the first three Sentinel sensor platforms constitutes a unique European monitoring capacity for land (and maritime) surface characterization that can be applied globally and consistently to forestry applications. While technical superior to any other current monitoring capacity, the interoperability with the US Landsat 8 and possible other sensors that may provide high resolution imagery under free and open licenses, will further increase essential data availability. The listing of technical details above is important to appreciate the differences between the high resolution Sentinel capacities compared to any of the previous or existing space borne EO capacities in this resolution domain. This is particularly relevant for their use in tropical forest mapping and monitoring applications, as follows: Satellite imagery such as provided by the Landsat satellites (30 m and 15 m resolution), are used widely for forest mapping and monitoring in the tropics. However maps derived from 30m resolution data are affected by a certain level of uncertainty due to limited spatial resolution or to restricted availability of imagery at optimal periods. These uncertainties limit and may, in certain conditions, even prohibit the use of such data, like for assessing levels of degradation in tropical dry forests. The technical quality of the Sentinel sensors will significantly enhance the separation of land cover classes in the forest land use, both for forest land (i.e. forest types) and the complex domain of agriculture and forest mosaics (including shifting cultivation). The m spatial resolution of S2A (and S2B), combined with 10 days (5 days with both S2A and S2B) revisit frequency will resolve forest cover status and small scale disturbances delineation at plot / log level detail. Slower forest conversion changes, in particular progressive removal of fuel wood or agricultural land abandonment leading to forest regrowth, will benefit from the high spatial details and the possibility to select the most relevant seasonal acquisitions. The complementarity of VNIR and SWIR channels (from S2) is unique in this respect as well. Furthermore, the spectral compatibility of S2 with Landsat-8 and much improved atmospheric correction will greatly expand inter-sensor consistency and data fusion potential. Forest degradation occurs due to different processes, including unsustainable logging, shifting cultivation, firewood collection or burning. It leads to a reduction of biomass, opening of forest canopies and changes in the structure of forests, but also modifies species composition thus affecting ecosystem services, including future potential for carbon capture and storage. Most forest degradation could ultimately be detected by remote sensing methods, but optimal

8 Version 4-24 March Page 8 approaches and methodologies for monitoring forest degradation are likely to vary depending on the type and location of the degradation as well as on forest types concerned. The finer spatial resolution (10m) and the higher temporal frequency (5 to 10 days revisit time) of Sentinel-2 acquisition will allow to detect and to quantify forest degradation in tropical countries more accurately and regularly than possible from current medium-resolution satellite imagery. Consequently, in the near future, satellite imagery from the Sentinel-2 satellite sensor will provide potential for step change in the assessment of forest conditions. The long term sustained nature of the Copernicus programme, with currently an outlook for >10 years of continuous, global observations and a provision for, technologically improved, second generation sensors, provides a basis to initiate long term forest monitoring programmes that rely on inter-annual, inter-season and inter-regional trend analysis. The latter requires a number of years of observations to establish a stable reference trend. The full, free and open licensing scheme for Sentinel data will enable global uptake of the imagery and is essential to establish novel collaborative arrangements where knowledge inference and sharing will be the basis to ensure globally consistent forest monitoring outputs, with common quality and accuracy standards, which are fully verifiable. This has never been possible with restrictive data licensing schemes. Integration with other free and open EO sources (e.g. Landsat-8) is natural and will hopefully stimulate other initiatives that will establish free and open access to this category of imagery as the default. The combination of long term sustainability with open access to the data will stimulate anchoring applications in a wider range of user domains, both operating at national and regional scales. Given the unique nature of the conditions set out above, one could argue that a relatively long period of experimentation and testing would be needed, before operational take up should be considered. After all, none have worked with such rich data at a global scale before, there are formidable data processing ( Big Data ) challenges, etc. However forest monitoring programmes based on Landsat imagery are well established in a few countries since many years (Brazil, India, Indonesia, and Mexico) and have an active user community which is fully able to integrate technological advances in a rapid and consistent manner. In particular, regional monitoring capacities will benefit immediately from the new data availability, as open access to the data combined with open source post-processing software (e.g. the Sentinel toolboxes), greatly facilitate automated workflows for data integration. Furthermore, unnecessarily delaying operational take-up of the Sentinel data flow would pose a serious risk to the success of the Copernicus programme. Fortunately, the rate of growth of users downloading S2A imagery (95,000 image scenes downloaded between beginning of December 2015 and end of February 2016 representing approx. 95 Terabytes of data 8 ) is clear evidence of the healthy user appetite for these new data sets, across science and application domains. (End of document) 8 from a presentation by Bianca Hoersch, ESA Sentinel-2 Mission Manager, at GFOI Forum, 22 Feb 2016