利用ISCCP D2资料分析了青藏高原云宏观参量的时空分布特征,结合NCEP资料分析了不同云类与降水和气温的关系,利用CERES SSF MODIS Edition 3A资料分析了云对地气系统的辐射强迫作用.结果表明,青藏高原地区云量分布整体呈自东向西减少的态势;总云量、低云云量、总光学厚度和总云水路径的分布形势很相似;水高积云、水积云、卷云和冰高积云的云水路径及云光学厚度均较小,冰层云、冰雨层云和深对流云的云水路径及云光学厚度均较大;出现最多的是卷云,最少的是冰层云、冰层积云、冰积云和冰雨层云;青藏高原地区的水积云、水高积云、水高层云、卷云和卷层云的云量与降水一致.近20 a,中高云量在青藏高原地区呈上升趋势,低云量则呈明显下降趋势,该结果可能导致青藏高原地区地面气温升高.青藏高原地区云的短波辐射强迫主导着云的净辐射强迫效应,且具有显著的季节变化.
Climate characteristics of clouds and their influence on the land-atmosphere system in the Qinghai-Tibet Plateau
ISCCP data were used to analyze the spatial and temporal distribution characteristic of cloud parameters in the Qinghai-Tibet Plateau.The relationships between different classes of clouds and rainfall and temperature from NCEP data were determined.The cloud radioactive effects on the land-atmospheric system over the Qinghai-Tibet Plateau were studied by using CERES SSF MODIS Edition 3A data,with the results that the mean cloud amount,low cloud amount,cloud optical thickness and cloud water paths became less or fewer from the east to west;as regarding the cloud water path and cloud optical thickness the stratus,nimbostratus and deep convective of ice were the largest while altocumulus and cumulus of liquid,cirrus and altocumulus of ice were the smallest;the frequency of occurrence for cirrus was the highest while ice occurring frequency of stratus,stratocumulus,cumulus and nimbostratus were lower;the distribution of cumulus,altocumulus,altrostratus of liquid,cirrus and cirrostratus were the same with the mean cloud amount;for nearly 20 years the trend of mid and high cloud amount were rising while the trend of the low cloud amount was in a decline,leading to rising temperature;and that the cloud shortwave radioactive forcing dominated the net radioactive forcing and varied remarkably with seasonal changes.
NETL
NSTL
万方数据
维普
