青藏高原地表特征时空分布

通过利用地理信息数据库、卫星反演参数、气象观测数据,分析了我国青藏高原地区地表植被覆盖、地表反照率分布、地表蒸发分布、地表积雪分布.结果显示,随着青藏高原地表年平均气温的显著升高,青藏高原部分区域地表覆盖特征也发生了改变.在青藏高原南缘湿润大区降水充分地区,地表反照率相对较低,潜热蒸发量最大,1982～2000年期间地表植被覆盖呈明显增加趋势.青藏高原地区积雪覆盖在各个气候区域也呈现同步变化特征,自1970～1989期间,降雪量呈持续增加趋势,但之后至2000年期间,全区降雪量呈下降趋势,其中积雪覆盖变化最强烈的时段发生在10月～4月之间,变化幅度最大的区域位于青藏高原的东南部区域.

The Spatiotemporal Distribution of Land Surface Features in the Tibetan Plateau

The surface distributions of vegetation, albedo, evaporation and snowfall in the Tibetan Plateau were analyzed by using GIS database, satellite remote sensing data and meteorological data. The results show that the land surface features have changed with annual mean temperature increasing in the Plateau. In the south of the Plateau, where the rainfall and evaporation were more and the albedo was lower than other regions, there was obviously an increasing vegetation cover on the land surface from 1982 to 2000. Meanwhile, the snow cover also shows the similar changes. The snowfall had a continuous increasing trend from 1970 to 1989, but it decreased thereafter up to 2000 in the whole Plateau. The intense seasonal variation of the snow cover takes place between October and following April, and the biggest variation locates in the southeast of the Plateau.