SMAP Enhanced L1C Radiometer Half-Orbit 9 km EASE-Grid Brightness Temperatures, Version 1

This enhanced Level-1C (L1C) product contains calibrated, geolocated, brightness temperatures acquired by the Soil Moisture Active Passive (SMAP) radiometer during 6:00 a.m. descending and 6:00 p.m. ascending half-orbit passes. This product is derived from SMAP Level-1B (L1B) interpolated antenna temperatures. Backus-Gilbert optimal interpolation techniques are used to extract maximum information from SMAP antenna temperatures and convert them to brightness temperatures, which are posted to a 9 km Equal-Area Scalable Earth Grid, Version 2.0 (EASE-Grid 2.0) in three projections: global cylindrical, Northern Hemisphere azimuthal, and Southern Hemisphere azimuthal.该增强型一级C（Level-1C, L1C）产品包含由土壤湿度主动被动（Soil Moisture Active Passive, SMAP）辐射计在上午6时降轨半轨过境、下午6时升轨半轨过境时段采集的经定标与地理定位的亮温数据。本产品的数据源为SMAP一级B（Level-1B, L1B）级插值天线温度数据。研究采用巴克斯特-吉尔伯特（Backus-Gilbert）最优插值技术，从SMAP天线温度数据中提取最大信息量并转换为亮温数据，随后将其网格化至9公里分辨率的等面积可扩展地球网格2.0版（Equal-Area Scalable Earth Grid, Version 2.0, EASE-Grid 2.0），该网格支持全球圆柱、北半球方位及南半球方位三种投影方式。