地球轨道偏心率变化对东亚季风气候模拟的影响

采用较为真实的椭圆轨道代替了原区域气候模式中的圆近似轨道,并进行了10年模拟试验,用以了解该模式对东亚季风区气候年际变化的模拟能力,同时比较地球轨道参数计算变化对现代东亚季风气候模拟的影响.结果表明:当把模式中的地球轨道计算从圆形改为椭圆时,中国东部的降水模拟有所改进,东亚地区的温度、降水、比湿等气候要素均出现夏季降低(减少)而冬季升高(增加)的季节变化趋势,而且亚洲冬、夏季风也均有减弱.但从总体上说,现代气候状况的模拟对地球公转轨道的计算方案不敏感.通过该工作的模拟研究说明,对较短时期的现代气候模拟,地球公转轨道采用圆近似是可行的.

The Effects of Changes of Earth Orbital Parameters on East Asian Monsoon Simulation

The authors developed the calculating method of the earth orbital parameters in a regional climate model and operated 10 years' simulations to compare the influence of changes of earth orbital parameters on modern east Asian monsoon. From these studies, some preliminary conclusions could be drawn as follows: A slight improvement takes place in the precipitation simulation in East China after modified the earth orbital parameters from circle to ellipse in the model. The climate elements, e.g. temperature/precipitation/specific humidity etc., reveal a seasonal variation trends that fall (decrease) in summer and rise (increase) in winter, and the winter/summer monsoon of Asia are weakened. In general, the results of simulation would not be notably affected by change of computing methods of earth orbit parameters. So it is viable to adopt a circle approach in the earth orbit calculation while simulating modern climate in a shorter span.