关键词: 气候变化, 排放情景, 未来50年, 气温, 降水, 周期, 鄱阳湖流域

Abstract:

The possible climate change for three emission scenarios (SRESA2,A1B,B1) has been predicted by ECHAM5/ MPIOM.Based on the projected data,temperature and precipitation,changes during 2000~2050 over Poyang Lake basin are analyzed.It is found that temperature will increase significantly in the future 50 years for the three emission scenarios,of which magnitude and velocity are much higher than in the 1990s.For A1B,the temperature will rise 1.62°C which is the most significant parameter in the three scenarios.Precipitation changes are much more complicated.The downward trend of precipitation will dominate in the future 30 years.For A2,precipitation will decrease 6.7% (anomalies compared with the average of 1961~1990) during 2021~2030.While in the following 20 years,the upward trend is observed.For B1,it will increase 10.8%.As for the seasonal change,precipitation will have positive trend from January to June,but have negative trend from September to December.If the condition occurs,there may be droughts intermittently in summer,autumn and winter like those occurred in the period of 2003~2005,but the drought may be severe for the period of 2011~2030.The geographical distributions of precipitation indicates that changes in the eastern and southern parts are more significant than in the western and the northern parts.There is a significant 20a periodicity for the emission scenarios A2 or A1B,while 30a periodicity for B1.The increase of anthropogenic emission may weaken the magnitude of oscillation and change the length of periodicity.

Key words: climate change, three human emission scenarios, future 50 years, temperature, precipitation, periodicity, Poyang Lake Basin