青藏高原地气温差与印度洋海气温差的相互影响

青藏高原和印度洋均对我国气候有重要影响,研究高原和印度洋的热力状况及其耦合关系对全面了解我国的天气现象具有重要意义.利用1981―2010年(30a)欧洲中心ERA-interim的青藏高原和印度洋温度资料,以及NCEP/NCAR的垂直速度和风速资料,分析了青藏高原地气温差和印度洋海气温差的特征及其相互影响.结果表明,高原冬、夏季地气温差有所区别:冬季地气温差呈东北-西南向的带状分布,在高原中部、西南边界喜马拉雅山脉地区和东南边界出现了较大的负值中心,其他地区均为正值;夏季地气温差均为正值,远大于冬季.在印度洋,海气温差冬、夏均为正值,EOF1空间分布均出现正负交替的现象,但冬季为东西向带状分布,夏季为西北-东南向分布.高原和印度洋相互影响且互相制约:在冬季,印度洋对高原地气温差有正反馈,高原对印度洋则有负反馈,夏季相反.本结果可为进一步研究青藏高原和印度洋对亚洲气候的共同作用提供参考.

A study on the interaction between ground-air temperature differences over the Qinghai-Tibet Plateau and sea surface-air temperature differences over the Indian Ocean

Because both the Qinghai-Tibet plateau and the Indian Ocean have important influences on our climate, the study on their thermal conditions is of great significance to the comprehensive understanding of the weather phenomenon in China. Based on the Qinghai-Tibet Plateau temperature dataset and the Indian Ocean temperature dataset from European Centre ERA-interim, and NCEP/NCAR's vertical speed and wind dataset, the characteristics of differences between ground and air temperature over the Qinghai-Tibet Plateau and those between sea surface and air temperature in the Indian Ocean, as well as the interactions between them are analyzed. Results show that temperature difference of the Qinghai-Tibet Plateau exhibits a northeast-southwest zonal distribution in winter. In the central plateau, it shows a negative strip, Himalayan region and southeast border in southwest plateau is also a large negative center, while positive in the rest region; In summer, the temperature difference is positive, much greater than that in winter. In the Indian Ocean, the temperature difference in winter and summer is positive, the abnormal changes of summer and winter are positive and negative alternate, but the belt region in winter is a shape from east to west, in summer, from northwest to southeast. In winter, the Indian Ocean has a negative impact on the plateau, while the plateau is positively correlated with the Indian Ocean, which is just opposite during the summer. The plateau and the Indian Ocean interact and constrain each other. The results will provide some references for the further research on the common role of the Tibetan Plateau and the Indian Ocean in the Asian climate.