GPM-IMERG

GPM IMERG Final Precipitation L3 Half Hourly 0.1 degree x 0.1 degree V06

The Integrated Multi-satellitE Retrievals for GPM (IMERG) algorithm combines information from the GPM satellites to estimate global precipitation. IMERG is the continuation of TRMM. The latest Version 06 combines the precipitation estimates collected by the TRMM satellite (2000 - 2015) with the estimates from the GPM satellite (2014 - present).

The dataset has a spatial resolution of 1 X 1 degree and a temporal resolution of 30 minutes. The temporal coverage starts on 2000-06-01 to  present with about 3 months of delay.

More information is available on the NASA GPM website and on the GES DISC website.

We download the data from their hyrax server, using the opendap protocol, so we can get it in netcdf4 format instead of the original HDF5. We are currently updating the data with a monthly frequency.

Citation

Huffman, G.J., E.F. Stocker, D.T. Bolvin, E.J. Nelkin, Jackson Tan (2019), GPM IMERG Final Precipitation L3 Half Hourly 0.1 degree x 0.1 degree V06, Greenbelt, MD, Goddard Earth Sciences Data and Information Services Center (GES DISC), Accessed: [Data Access Date]10.5067/GPM/IMERG/3B-HH/06

GPM-IMERG at NCI

The GPM data is available, as part of the Precipitation datasets collection, in:

/g/data/ua8/Precipitation/GPM

The original data is divided in folders by year

<yyyy>/3B-HHR.MS.MRG.3IMERG.<yyyymmdd>-S<hhmmss>-E<hhmmss>.<time-fo-day-in minutes>.V06B.nc4

Where S<hhmmss> is the start timestamp,  E<hhmmss> is the end timestamp, these are followed by the time of the day expressed as minutes starting form 0000.

As an example:

2019/3B-HHR.MS.MRG.3IMERG.20191231-S233000-E235959.1410.V06B.nc4

We also provide a concatenated version with monthly files:

/GPM/concat/gpm_3imerg_v06b_<yyyymm>.nc

This is produced using cdo to concatenate the original files

cdo --history  -L  -s  -f nc4c  -z zip_5  cat 3B-*${yr}${mn}*-S*.nc4   gpm_3imerg_v06b_${yr}${mn}.nc