基于多源遥感与再分析数据估算塔克拉玛干沙漠地表净辐射日变化

作为世界第二大流动性沙漠，塔克拉玛干沙漠独特的陆表水热交换过程直接影响中国乃至全球的大气环流运动。将静止气象卫星FY-2F地表温度产品、极地轨道卫星MODIS陆表产品与中国区域高时空分辨率地面气象要素驱动数据集（CMFD）结合，反演得到时间分辨率为3 h、空间辨率为0.1°的2017年塔克拉玛干沙漠地表净辐射，利用塔中气象站观测值验证反演结果，并分析地表净辐射的时空变化特征。结果表明：（1）利用卫星遥感与再分析资料获取的地表特征参数与实测值误差较小，决定系数R²均在0.8以上。（2）地表净辐射模拟值与地面实测值具有较好的一致性，决定系数R²为0.967，均方根误差RMSE为29.193 W·m^-2。（3）地表净辐射日变化呈现明显的单峰型特征：早晚值较低，正午值最高，并且夜间值基本为负且变化幅度不大。（4）地表净辐射夏季>春季>秋季>冬季。（5）沙漠边缘散布的绿洲和农田地区净辐射值最高，沙漠腹地次之，沙漠南缘的昆仑山和阿尔金山冰川覆盖地区净辐射值最低。

Estimation of hourly surface net radiation in Taklimakan Desert based on multi-source remote sensing data and reanalysis data

The Taklimakan Desert is the second-largest flow desert in world， and its unique land-atmosphere interactions process directly affects the atmospheric circulation in China and even the world. Based on geostationary meteorological satellite data （FY-2F）， polar-orbiting satellite Data （MODIS）， and China Meteorological Forcing Dataset （CMFD）， 3-hourly surface net radiation at a spatial resolution of 0.1° in Taklimakan Desert is derived. The results shows that： （1）There is a good agreement between ground observed data and the surface characteristic parameter derived from satellite and reanalysis data， and the coefficient of determination （R²） is above 0.8. （2）The estimated surface net radiation is in good agreement with the in situ measurements. The coefficient of determination （R²） is 0.967， and the root means square error （ RMSE） is 29.193W·m^-2. （3）At the daily temporal scale， the surface net radiation increases with sunrise and reach their maximum at midday before decreasing again with sunset， and net radiation is small in summer and large in winter. （4）Its spatial distribution is consistent with general meteorological conditions of the Taklimakan Desert. There are the highest net radiation values in oasis and farmland， followed by desert hinterland， and there are the lowest net radiation values in Kunlun Mountains and Altun Mountains.