National Centers for Environmental Prediction (NCEP) Climate Prediction Center Merged Analysis of Precipitation (CMAP)

The CPC Merged Analysis of Precipitation (CMAP) is a technique which produces pentad and monthly analyses of global precipitation in which observations from rain gauges are merged with precipitation estimates from several satellite-based algorithms (infrared and microwave). The analyses are are on a 2.5 x 2.5 degree latitude/longitude grid and extend back to 1979. There are two merged precipitation datasets:
1) rain gauge, 5 satellite estimates( GPI, OPI, SSM/I scattering, SSM/I emission and MSU), and numerical model predictions;
2) rain gauge, 5 satellite estimates( GPI, OPI, SSM/I scattering, SSM/I emission and MSU).
Where OPI stands for OLR-based precipitation index. These datasets contain rain amount and rain rate on a 2.5 degree latitude x 2.5 degree longitude global grid ( 88.75N - 88.75S, 1.25E – 358.75E).