Abstract:

The climate is changing due to higher concentrations of greenhouse gases. If concentrations continue to increase, climate change will be more severe in this century based on climate models project. And it will have significant impacts on many human sectors, especially on agriculture. Agriculture is the foundation of society, especially for China with large population. Wheat is the second most important crop in China. Therefore, it is necessary to assess the impacts of climate change on wheat in China. In order to predict the future risk of climate change on Chinese wheat production, firstly, fifteen- year ECMWF re- analysis data (1979~1993) is used as quasi- observed boundary conditions to drive regional climate modeling system- PRECIS, then the dataset is employed to test the effects of feeding CERES-Wheat model with RCM daily outputs directly via comparing the simulated results and the station observation. Based on the above validation, two wheat stations (Ding Xi and He Fei) were selected to assess the possible changes of future two production under IPCC SRES A2 & B2 scenarios. The rained and irrigated wheat production without and with CO2 fertilization effect, were simulated respectively. It is shown that: regardless of A2 or B2 scenarios, the future climatic change will increase wheat yield both in Dingxi and Hefei to some extent, but the range increased differs greatly. The yield increasing effect of A2 scenario will be generally greater than B2 scenario, the irrigated wheat will benefit more than rainfed wheat, the winter wheat (Hefei ) has larger increasing degree than spring wheat (Dingxi ). With the directly fertilizer effect of CO2, all the treat will increase by a large margin.

Key words: CERES- wheat mode, climate change, RCM