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This document describes the GeoTIFF translation of a precipitation climatology based on Version 7 Final IMERG. Click here to view the full documentation for the IMERG V07 Daily and Grand Climatology Products.

These climatology products contain the daily and “grand” climatological precipitation from the Integrated Multi-satellitE Retrievals for GPM (IMERG) 07B in netCDF4 and GeoTIFF formats. The IMERG Daily Climatology product is derived from the daily precipitation data by averaging the non-missing precipitation values in every 0.1° grid box for a specific day of the year, over a range of years.

The Integrated Multi-satelliE Retrievals for GPM (*IMERG*) is the unified U.S. algorithm that provides the multi-satellite precipitation product for the U.S. GPM team.

This FAQ document provides information specifically aimed at the Integrated Multi-satellitE Retrievals for GPM (IMERG) Version 07 for applications users. As of August 2024, both Initial Processing (IP) and retrospective processing (RP) for the IMERG Early, Late and Final products have been completed for Version 07. IMERG V07 involves a wide range of changes to all aspects of the product, many of which are implemented in response to feedback on V06, which was the first time the IMERG record spanned the TRMM and GPM eras.

This document describes the algorithm and processing sequence for the Integrated Multi-satellitE Retrievals for the Global Precipitation Measurement (GPM) mission (IMERG). This algorithm is intended to intercalibrate, merge, and interpolate “all” satellite microwave precipitation estimates, together with microwave-calibrated infrared (IR) satellite estimates, precipitation gauge analyses, and potentially other precipitation estimators at fine time and space scales for the Tropical Rainfall Measuring Mission (TRMM) and GPM eras over the entire globe.

The algorithm for the Integrated Multi-satellitE Retrievals for GPM (IMERG) has now been upgraded to Version 07.  IMERG V07 involves a wide range of changes to all aspects of the algorithm, many of which are implemented in response to feedback on V06, which was the first time the IMERG record spanned the TRMM-GPM eras.  IMERG V07 is being reprocessed for the entire TRMM-GPM record and thus supersedes all prior IMERG versions, as well as superseding the prior TRMM-based TMPA products (3B42, 3B43).

The L3GPROF algorithm provides monthly and daily mean precipitation and related retrieved parameters from the Level 2 GPROF precipitation profiling algorithm for the GPM core and constellation satellites.

Each L3GPROF product contains global 0.25o x 0.25o gridded monthly/daily unconditional means and pixel counts. Monthly product filenames start with 3A-MO or 3A-CLIM-MO, and daily product filenames start with 3A-DAY or 3A-CLIM-DAY.

This Level 3 GPROF Version 07 release involves the following changes from the previous
(Version 05) release:

1. Product format change:
Added dimension variables such as lat, lon, layer, lat_bnds, lon_bnds, layer_bnds. Removed
cloudIce variable but added graupel and latentHeating variables.
2. Total number of precipitation pixels (npixPrecipitation):
In Version 05, pixels with pixelStatus=0 and surfacePrecipitation > 0 are counted as
precipitation pixels. In Version 07, pixels with pixelStatus=0, surfacePrecipitation > 0 and

To address how NASA data can enable support of operations within the transportation and logistical sectors, the NASA Global Precipitation Measurement (GPM) Mission Applications Team, in collaboration with the Aerosols, Clouds, Convection and Precipitation (ACCP) Study Applications Impact Team (AIT), organized the virtual 2020 NASA GPM-ACCP Transportation and Logistics Workshop. 

At the end of 2020, PPS anticipates that it will replace the current FTP access to its Production data archive with FTPS and HTTPS access. In choosing between FTPS and HTTPS, select HTTPS in situations where firewall restrictions prevent FTPS access.