基于SMOPS降尺度的蒸发比估算研究

Evaporative Fraction Estimation Based on SMOPS Data Downscaling

针对研究区土壤湿度观测资料匮乏、无法准确估算区域蒸发比的问题,提出一种完全基于遥感数据的陆面蒸发比模拟估算方法,选取美国南大平原地区2019年52个晴天的MODIS和SMOPS数据,利用特征空间框架下的地表能量平衡原理计算了M_(MTVDI),同时对SMOPS数据进行了粗分辨率的像元降尺度,最终得到1km分辨率下的土壤水分和蒸发比,并与站点数据进行了对比验证。结果表明,该方法可有效模拟出蒸发比的空间分布,并解释了蒸发比与其他影响因素之间的关系。

Aiming at the problem of the lack of soil moisture observation data in the study area and the inability to accurately estimate the regional evaporative fraction,a simulated estimation method of land surface evaporation ratio based remote sensing data was proposed.This paper selected SMOPS and MODIS data about 52 clear days in the USA south plains in 2019.The surface energy balance of principle feature space was used to calculate the M_(MIVDI).Meanwhile the coarse resolution pixel downscaling of SMOPS data was studied.Eventually 1 km resolution of SM and EF was obtained,and site data was used for validation.The results show that the spatial distribution of evaporation ratio is simulated effectively,and the relationship between evaporation ratio and other influencing factors is explained.