SAFARI 2000 GPCP DAILY PRECIPITATION, 1-DEG, 1999-2001

The Global Precipitation Climatology Project (GPCP) is an international project designed to provide improved long-record estimates of precipitation over the globe. The general approach is to combine the precipitation information available from several sources into a final merged product that takes advantage of the strengths of each data type. The GPCP has promoted the development of an analysis procedure for blending the various estimates together to produce the necessary global gridded precipitation fields. The currently operational procedure is based on Huffman et al. (1995) and has been used to produce the GPCP Version 2 Combined Precipitation Data Set, covering the period January 1979 through the present. The primary product in the Version 2 data set is a combined observation-only data set, that is, a gridded analysis based on gauge measurements and satellite estimates of rainfall. Beginning in October of 1996, the GPCP began producing 3-hourly merged global infrared (IR) brightness temperature (Tb) histograms on a 1 degree by 1 degree grid, which became the impetus for this product, also known as the 1 degree daily (1DD) product. The data set prepared for SAFARI 2000 has been extracted from the 1DD data set for the years 1999, 2000, and 2001.The Global Precipitation Climatology Project (GPCP) is an element of the Global Energy and Water Cycle Experiment (GEWEX) of the World Climate Research program (WCRP). The 1DD is produced by the GPCP Merge Development Centre (GMDC), located at NASA's Goddard Space Flight Center in the Laboratory for Atmospheres.

全球降水气候学计划（Global Precipitation Climatology Project, GPCP）是一项国际合作项目，旨在提供精度更优的全球降水长期序列估算结果。其核心技术路径为整合多源降水观测信息，生成兼顾各类数据类型优势的最终融合产品。GPCP推动了融合多种降水估算结果的分析方法研发，以生成所需的全球网格化降水场。当前的业务化分析流程基于Huffman等人1995年的研究成果，已被用于生成GPCP第二版联合降水数据集，时间覆盖范围为1979年1月至今。该数据集第二版的核心产品为纯观测联合数据集，即基于雨量站测量数据与卫星降雨估算结果构建的网格化分析产品。1996年10月起，GPCP开始生成分辨率为1°×1°的逐3小时融合全球红外（infrared, IR）亮温（brightness temperature, Tb）直方图，这一成果成为本产品（亦称为1°每日（1DD）产品）的研发契机。为SAFARI 2000项目制备的数据集提取自1999至2001年的1DD数据集。全球降水气候学计划（GPCP）隶属于世界气候研究计划（World Climate Research Program, WCRP）下的全球能量与水循环实验（Global Energy and Water Cycle Experiment, GEWEX）。1DD产品由位于美国国家航空航天局（National Aeronautics and Space Administration, NASA）戈达德太空飞行中心大气实验室的GPCP融合研发中心（GPCP Merge Development Centre, GMDC）负责生成。