Climate Change Assessment and Decelerating Food Production Trends in India

Transcription

1 Climate Change Assessment and Decelerating Food Production Trends in India Presentation made at NRCCC, IIT Delhi 5 March, 2010 K. Krishna Kumar Indian Institute of Tropical Meteorology, Pune (krishna@tropmet.res.in)

2 Indian Trends: 0.51C/100yr ( ); 0.20C/10yr ( ) Global Trends: 0.82C/100yr ( ); 0.24C/10yr ( )

3 Possible Role of Aerosols in Indian Temperature Trends Tmax Nov-May North of 20N Tmax Nov-May South of 20N Tmin Nov-May Trend = Aerosols Flux (W/m 2 ) Year Radiation Received At the surface

4 Expected Future Changes Under Increased GHG Conditions IPCC-AR4

5 IPCC AR4 Simulations Historical run: 20th Century simulation Future climate simulations (initial conditions from end of the 20th Century simulation): Committed Climate Change : hold concentrations at year 2000 SRES A2 to 2100 SRES A1B to 2100 then fix concentrations (~720 ppm) for an additional century (with one realization extended to 2300) As above but with SRES B1 (~550 ppm) IPCC-SRES Global Mean Indian Region The model simulation data of the above runs are available through IPCC-DDC/ PCMDI, USA and has already exceeded 40TB

6 Some Aspects of Asian Summer Monsoon Rainfall and Its ENSO Teleconnections as simulated by AR4 Models in 20 th Century Mean Monsoon Rainfall Monsoon and ENSO Tropical Waves; MJOs Krishna Kumar et al, 2010 Lin et al. 2006, J. Climate

7 Observed and IPCC-AR4 Ensemble mean Monsoon Rainfall and Annual Surface Temperature

8 Expected Future Changes in Rainfall and Temperature over India under IPCC SRES A1B GHG Scenarios Krishna Kumar et al, 2010

9 Expected Future Change in Monsoon Rainfall and Annual Surface Temp for 2020 s, 2050 s and 2080 s Rainfall Temp Krishna Kumar et al, 2010

10 Other Expected Changes in Monsoon Features Annual Cycle Length of Season Monsoon Variability Monsoon & ENSO Krishna Kumar et al, 2010

11 Cascade of uncertainty in climate change prediction Socio-Economic Assumptions Policy Responses: Adaptation and Mitigation Emissions Scenarios Concentration Calculations Biogeochemical/Chemistry Models Global Climate Change Simulation AOGCMs, Radiative Forcing Regional Climate Change Simulation. Regionalization Techniques Impacts Natural Forcings Interactions and Feedbacks Land Use Change Impact Models

12 High-Resolution Regional Climate Change Scenarios Dynamical Downscaling using Regional Climate Models

13 PRECIS Runs at IITM (Resolution: 50km) Evaluation experiment using LBCs derived from ERA-15 ( ) LBCs from Hadley Centre Models Baseline ( ) 3 members A2 scenario ( ) -3 members B2 scenario ( ) 3 Members of QUMP ( ) A1b LLBCs from ECHAM Baseline ; A2 scenario : ; B2 scenario :

14 PRECIS captures important regional information on summer monsoon rainfall missing in its parent GCM simulations. HadCM3 PRECIS

15 Possible Climate Change impacts are examined in the: Extremes in rainfall and temperature Onset and advance of Monsoon Active/break cycles Intensity and frequency of Monsoon Depressions

16 Projections of Regional Tmax and Daily Rainfall Changes Highest daily Tmax (C) in The Baseline Period Expected change in Tmax in Future under A2 Expected change in No. of Rainy Days In future under A2 Expected change in Rainfall Intensity in a rainy day in future Krishna Kumar et al, 2010

17 Impact of Growing Season Rainfall and Night time Temps on Rice Yields Y in India Tmin ( C) Baseline SRES A2 Tmax ( C) Impact of Daily Tmax on the Mortality rate at Delhi (Source: Hazat at et al 2005) Krishna Kumar et al, 2010

18 Decelerating Food Production Trends in India Cristina Milesi 1, Arindam Samanta 2, Hirofumi Hashimoto 1, K. Krishna Kumar, Sangram Ganguly 2, Prasad S. Thenkabail 3, Ashok N. Srivastava 4, Ramakrishna R. Nemani 5, R. B. Myneni 2 1 California State University Monterey Bay; 2 Boston University 3 U. S. Geological Survey; 4 Intelligent Systems Division, NASA Ames Research Center; 5 Biospheric Science Branch, NASA Ames Research Center Paper appearing in Remote Sensing

19 2.9% AVERAGE ANNUAL RATE OF GROWTH IN WORLD GRAIN YIELDS PER DECADE Green Revolution 1.6% 1990s PROJECTED 0.8% 2040s FAO; International Food Policy Research Institute

20 Change (%) in rate of food grain production in relative to Over the last decade, 31 out of 41 countries that hold 90% of the water-limited croplands show a decline in annual average growth rate of food grain production. Food grain: cereals+coarse grains+pulses Data from FAOSTAT 20

21 Annually Integrated NDVI trend in indvi calculated from GIMMS G NDVI = NIR RED / NIR+RED

22 45% of the water-limited tropical croplands show a decline in relative growth of integrated NDVI over the last decade DECLINE IN AGRICULTURAL PRODUCTIVITY IN THE SEMI-ARID TROPICS DURING THE LAST DECADE % change in vegetation greenness during compared to as calculated from GIMMS-G NDVI NDVI = NIR RED / NIR+RED

23 Change (%) in rate of food grain production in relative to Change (%) in trend of peak annual precipitation in relative to

24 Spatio-temporal deceleration in food grain production Change in indvi growth rate for decade ( ) compared to the decade ( )

25 Spatio-temporal deceleration in food grain production Average rainfall=911mm/yr Average rainfall=161mm/yr

26 In major food grain - producing states, 50-80% of irrigation water comes from groundwater Thenkabail et el., 2009

27 Relative increase (%) in water consumption due to increased rabi (dry season) crop production Kcb m = ( NDVI ( NDVI NDVI )) max max NDVI m min AET y = m= 12 m= 1 Kcb m PET m ΔWC = [( AET nyears) ( P E) ] trend mean ΔWC Er-Raki et al., 2007

28 Relative increase (%) in water consumption due to increased rabi (dry season) crop production Central Groundwater Board ΔWC

29 Kharif Mean annual T =27.1 C Rabi Mean annual T =22.5 C Warming climate, decline in cropped area and urbanization are also possibly contributing to decreasing food grain production Change in nightlights from DMSP/OLS composite R 2008 G 2000 B

30 Thank you!