基于MODIS的中国地表反照率特征分析

Analysis of surface albedo over China based on MODIS

地表反照率的细微变化能够深刻影响地表能量收支平衡,引起区域以至全球的气候发生变化。利用MODIS地表反照率产品MCD43A3(V006)及其质量控制产品MCD43A2(V006),建立了空间分辨率500m×500m的中国区域地表反照率数据集,并结合数理统计方法,分析了2003-2017年中国地表反照率的空间分布及变化特征。结果表明:近15年中国地表反照率呈下降趋势,多年平均地表反照率为0.192,青藏高原和天山及其以北是高值区,同时天山及其以北和东北地区的地表反照率年内变化较为剧烈。青藏高原是地表反照率异常变化最敏感的区域。鄂尔多斯高原、青藏高原东部和新疆东部等地的冬季平均地表反照率呈较明显的减小趋势,可能对冬季地表反照率整体呈下降趋势影响较大。

Subtle changes in surface albedo can profoundly affect the balance of surface energy,and cause regional and global climate changes.Using MODIS surface albedo product MCD43 A3(V006)and its quality control product MCD43 A2(V006),the Chinese surface albedo data set was established with spatial resolution of 500 m×500 m.Combined with mathematical statistics analysis method,the spatial distribution and variation of surface albedo over China from 2003 to 2017 were analyzed.The results are as follows:In the past 15 years,the surface albedo over China showed a decreasing trend.The multi-year average surface albedo was 0.192.The Qinghai-Tibet Plateau,the Tianshan Mountains and its north were high-value areas.At the same time,the surface albedo of the northeast regions of China,the Tianshan mountains and its north had changed drastically during the year.The Qinghai-Tibet Plateau was the most sensitive area for abnormal changes in surface albedo.The average surface albedo in winter in the Ordos Plateau,the eastern Qinghai-Tibet Plateau and eastern Xinjiang showed a significantly decreasing trend,which may have a greater impact on the overall downward trend of surface albedo in winter.