摘要
Using the automatic weather station data obtained from the Tibetan Plateau (TP), the normalized dif- ference vegetation index and the monthly precipitation data of China and by the methods of correlation and composite analysis, preliminary analytical results are achieved concerning the relationships be- tween TP NDVI change and its surface heat source and precipitation of China. The results of our re- search may lead to the following conclusions: (1) A positive correlation relationship exists between TP NDVI change and its surface heat source, including the sensible heat and the latent heat. As to the correlation of the former, it is more remarkable in western TP than in eastern TP, and as to the correla- tion of the latter, however it turns out contrary. (2) With the improvement of TP vegetation, its surface heat source of every season is also mainly reinforced, especially in summer. As to the contribution of the sensible heat and the latent heat to the increment of the TP surface heat source intensity, the for- mer is comparatively more significant than the latter in winter and spring, while in summer and autumn, the two have almost the same importance. (3) The correlation coefficient between summer NDVI over TP and the corresponding period precipitation of China displays a belt distribution of "+?+" from south to north China. (4) Anomalous surface heating field over TP derived from vegetation change is probably an important factor to affect summer precipitation of China.
Using the automatic weather station data obtained from the Tibetan Plateau (TP), the normalized difference vegetation index and the monthly precipitation data of China and by the methods of correlation and composite analysis, preliminary analytical results are achieved concerning the relationships between TP NDVI change and its surface heat source and precipitation of China. The results of our research may lead to the following conclusions: (1) A positive correlation relationship exists between TP NDVI change and its surface heat source, including the sensible heat and the latent heat. As to the correlation of the former, it is more remarkable in western TP than in eastern TP, and as to the correlation of the latter, however it turns out contrary. (2) With the improvement of TP vegetation, its surface heat source of every season is also mainly reinforced, especially in summer. As to the contribution of the sensible heat and the latent heat to the increment of the TP surface heat source intensity, the former is comparatively more significant than the latter in winter and spring, while in summer and autumn, the two have almost the same importance. (3) The correlation coefficient between summer NDVI over TP and the corresponding period precipitation of China displays a belt distribution of “+-+” from south to north China. (4) Anomalous surface heating field over TP derived from vegetation change is probably an important factor to affect summer precipitation of China.
基金
the National Natural Science Foundation of China (Grant No. 40675037)
the Key Program of the Sichuan Province Youth Science and Tech-nology Foundation (Grant No. 05ZQ026-023)
