The Version-2 Global Precipitation Climatology Project (GPCP) Monthly Precipitation Analysis (1979–Present)

Abstract

The Global Precipitation Climatology Project (GPCP) Version-2 Monthly Precipitation Analysis is described.This globally complete, monthly analysis of surface precipitation at 2.5Њ latitude ϫ 2.5Њ longitude resolution is available from January 1979 to the present.It is a merged analysis that incorporates precipitation estimates from low-orbit satellite microwave data, geosynchronous-orbit satellite infrared data, and surface rain gauge observations.The merging approach utilizes the higher accuracy of the low-orbit microwave observations to calibrate, or adjust, the more frequent geosynchronous infrared observations.The dataset is extended back into the premicrowave era (before mid-1987) by using infrared-only observations calibrated to the microwave-based analysis of the later years.The combined satellite-based product is adjusted by the rain gauge analysis.The dataset archive also contains the individual input fields, a combined satellite estimate, and error estimates for each field.This monthly analysis is the foundation for the GPCP suite of products, including those at finer temporal resolution.The 23-yr GPCP climatology is characterized, along with time and space variations of precipitation.