1. Uncertainties in Climate Change Projection – An example of monsoon precipitation over China as simulated by 2 simulations of a RCM GAO Xuejie National Climate Center, China Meteorological Administration International Conference on Climate Change Adaptation: Policy, Practice & Legislation Beijing, 2-4 July 2013

2. Uncertainties in the future emission scenarios Natural variability Incomplete knowledge of the climate and earth system which lead to the imperfect models Incomplete knowledge of some external factors in the future: solar, volcano, etc. More uncertainties in the regional scale: landuse, aerosol, lack of enough observation, etc. Multi-model ensemble is a good way to address some of the uncertainties Source of the uncertainties:

3. SRES scenarioRCP scenario

4. Annual mean surface air temperature as simulated/projected CMIP5 multi-models over China ( ) CMIP5 Projections

5. Annual mean precipitation as simulated/projected CMIP5 multi-models over China (mm)

6. RCM: the ICTP RegCM3 in both simulations, same configurations, similar domain FdR Driving field: NCAR/NASA FvGCM Simulation period: presenet day 1961-1990, future 2071-2100 Scenaior: SRES A2; Resolution: 20×20km MdR Driving field: CCSR/NIES/FRCGC MIROC3.2_hires Simulation period: 1951-2100 Scenaior: SRES A1B; Resolution: 25×25km Period of analysis: May-June-July-Ausgus-September, Present: 1961-1990, Future: 2071-2100 Observation: Precipitation: Xie et al. (2007), Temperature: CN05 (Xu et al., 2009) RegCM3 simulations driven by FvGCM and MIROC: Uncertainties in monsoon precipitation projections over China: results from 2 RCM simulations

7. Mean precipitation in MJJAS for 1961-1990 ( ). (a) Observations; and simulations by FvGCM (b), by FdR (c); by MIROC (d); by MdR (e)

8. Simulated changes in mean temperature (ºC) for MJJAS by (a) FvGCM; (b) FdR; (c) MIROC; (d) MdR

9. Agreement in the sign of projected precipitation change across model simulations. (a) between FvGCM and MIROC; (b) between FdR and MdR. Blue (red) indicates that both models simulate a >5% increase (decrease)

10. ACCC RCM study for uncertainties - 2 RCM driven by 2 GCM: HadCM3-Q0 – RegCM4 HadCM3-Q0 – PRECIS ECHAM5 – RegCM4 ECHAM5 – PRECIS

11. ! THANK YOU!