中国东部NDVI时空变化及对东亚夏季风响应

Temporal and Spatial Variations of NDVI and Its Response to East Asian Summer Monsoon in East China

基于SPOT-VGT NDVI、NCEP/NCAR 700 hPa经向风月平均再分析资料和东亚夏季风指数,分析了1998年4月—2008年3月期间中国东部NDVI年、季节时空变化特征及其对东亚夏季风的响应特征。结果表明,1999—2007年期间中国东部NDVI以0.07/10a速率极显著增加,在春季和夏季NDVI增加最多,而在冬季NDVI增加最少。NDVI在苏北、安徽北部和河南东部等地增加较多,而在长江三角洲和珠江三角洲一些地区减少较多。在中国东部30°N以北地区,NDVI在四季变化都较大,而在30°N以南地区,NDVI只在冬季和秋季变化较大。当夏季700 hPa平均偏南风抵达中国东部的纬度较高、东亚夏季风较强时,中国东部NDVI较高。

Temporal and spatial variations of NDVI and its response to East Asian summer monsoon in East China was analyzed based on the SPOT--VGT NDVI, NCEP/NCAR reanalysis monthly average data of meridional wind at 700 hPa and East Asian summer monsoon index from April 1998 to March 2008. The results indicate that NDVI in East China significantly increased with a linear trend of 0.07 per 10 year from 1999 to 2007, the most the increase in spring and summer is, and the least the increase in winter is. NDVI increased more in northern Jiangsu and Anhui, and eastern Henan, but decreased more in the Yangtze River Delta, and some regions of Pearl River Delta. In the regions to the Norther areas of 30°N in East China NDVI varied more in winter, spring, summer and autumn, but in regions to the souther areas of 30°N in east China NDVI varied more only in winter and autumn. The response of NDVI to East Asian summer monsoon is obvious. In summer, with higher latitude of the meridional south wind at 700 hPa level, and with stronger East Asian summer monsoon, the NDVI in East China is higher.