Earth System Modelling in support of NERC s Science for a Sustainable Future

Transcription

1 Earth System Modelling in support of NERC s Science for a Sustainable Future JULIA SLINGO NCAS Centre for Global Atmospheric Modelling The University of Reading

2 NERC s Science for a Sustainable Future Earth s Life-Support Systems: Water, biogeochemical cycles and biodiversity Climate Change: Predicting and mitigating the impacts Sustainable Economies: Identifying and providing sustainable solutions ALL REQUIRE EARTH SYSTEM MODELLING

3 Climate Change is happening..

4 6 And it is taking us into uncharted territory.. 5 IPCC Projections 2100 AD 3 N.H. Temperature ( C) Global Temperature ( C) 4

5 Climate change is not unprecedented. The earth system has been capable of rapid transitions in the past. But the present trends in CO2 and methane are outside those experienced on earth for the last 400,000 years..

6 Furthermore we are changing the chemical composition of the atmosphere in unprecedented ways.

7 ..so we need Earth System Models Models are our laboratory. We use them to explore forcing and feedbacks in the earth system, to test hypotheses, to understand past changes and to predict the future. Image: BMRC

8 A well-found Earth System Laboratory must use (i) Whole System Approach

9 NERC s Earth System Modelling Hierarchy Complexity/scale interactions RGCMs EX P TR AC EA BI LI LO TY HiGEM/HadCM3/HADGEM1 RI N & G TU & NI IN NG FAMOUS/FORTE FO RM IN G GENIE/C-Goldstein Box/EBM Ensembles/Exploring parameter space/multi-millennia

10 Year IS92e to 2100 then linear decline IS92a to 2100 then linear decline 1990 levels to 2100 then linear decline Year Land Ocean Year Temperature Change (K) CO2 Exchange (GtC yr-1) CO2 Emissions (GtC yr-1) Atmospheric CO2 (ppmv) Burning 4000 GtC Fossil Fuel Reserve Year Lenton (2000)

11 NERC s e-science GENIE Project: Flexible framework for modelling the Earth System Focus on long-term and paleo climate change issues EU-PRISM: FP5 Infrastructure Programme European Climate Modelling System based around a coupler Portable, efficient and user-friendly + diagnostics and visualisation

12 . (ii) Probabilistic Approach Because we must address: Initial condition uncertainty (includes natural variability) Model uncertainty Scenario uncertainty Initial condition information is ignored in current climate forecasts Source: Anne Pardaens, Hadley Centre

13 Model uncertainty in projections of changes in the Atlantic THC THC variability is focus of NERC s Rapid Climate Change Thematic Programme

14 . (iii) Regional Approach because global/nh means mask large regional differences

15 Regional patterns of climate change are complex Multi model ensemble annual mean temperature change for relative to under SRES A2 scenario But model uncertainty in land/sea warming ratio (representation of land surface & hydrological cycle key factors) Source: IPCC/Jonathan Gregory

16 Potential change in surface ozone by 2100 John Pyle, NCAS/ACMSU

17 ..and (iv) Weather Approach Climate is the statistics of the weather Tracks of individual cyclones which make up the storm tracks Interactions between space and time scales are important and extremes matter! Courtesy: Kevin Hodges ESSC

18 Hadley Centre model running on the Earth Simulator: ~10 resolution

19 NERC Consortium UK-HIGEM A national programme in Grand Challenge high resolution modelling of the global environment between NERC and the Hadley Centre NCAS/CGAM, NCAS/ACMSU, BADC, BAS, CEH, ESSC, SOC, U. Cambridge, UEA and the Hadley Centre

20 Why a move to higher resolution is necessary I: Complexity in the atmosphere Water vapour and window channel radiances from Meteosat-7 Same fields from HadAM3 at climate resolution

21 Better weather systems in a high resolution model Precipitation in HadAM3 with 150km (left) and 300km (right) atmosphere High pass (<10 days) 500hPa geopotential height variance ERA Climate resolution 2x climate res.

22 Why a move to higher resolution is necessary II: Complexity in the ocean. and as simulated by OCCAM 10 1/40 SSTs in the Gulf stream from infrared measurements aboard MODIS 1/120

23 Why a move to higher resolution is necessary III: Complexity in the land surface Heterogeneity of the land surface, vegetation and soil hydrology are key factors in determining local climate

24 Why a move to higher resolution is necessary IV: Complexity in the cryosphere AVHRR image of the southern Weddell Sea showing coastal polynyas (typically 100km x 20km). Polynyas are sites of intense air-sea interaction and play a major role in production of Antarctic bottom water

25 Earth System Models and Earth Observation Exploiting the unprecedented view of the Earth System from space provided by EOS and Envisat New windows on the world

26 The richness and complexity of the earth s ecosystems: The Global Carbon Cycle observed by SeaWiFS

27 But human activity cannot be ignored. % of land currently under cultivation. Area of world production for arable and permanent crops. Levelling off during last decade indicating exploitation of majority of suitable land?

28 Earth System Modelling within NERC seeks to: Integrate across disciplines Integrate across the hierarchy of models Address regional versus global scale problems Explore timescales from days to millennia

29 And finally Earth System Modelling and Prediction is entering a new and exciting phase with the increases in computing power