IMERG Early Run Example January 24th, 2020

Data

Precipitation data from the GPM and TRMM missions are made available free to the public in a variety of formats from several sources at NASA Goddard Space Flight Center. This section outlines the different types of data available, the levels of processing, the sources to download the data, and some helpful tips for utilizing precipitation data in your research.

Beginner Resources

Training

Tutorials

Data Visualization

Data FAQ

Learn about IMERG

 

Frequently Asked Questions

How do I get precipitation data for my specific location?

There are several sources for downloading and viewing data which allow you to subset the data to only include specific parameters and/or geographic locations. These include the GES DISCGiovanni and STORM. In Giovanni you can obtain data for a specific country, U.S. state, or watershed by using the "Show Shapes" option in the "Select Region" pane.

What happened to the TRMM Multi-satellite Precipitation Analysis (TMPA / 3B4x) data products?

The TRMM satellilte has been decommissioned and stopped collecting data in April 2015. The transition from the Tropical Rainfall Measuring Mission (TRMM) data products to the Global Precipitation Measurement (GPM) mission products has completed as of August 2019. The GPM IMERG dataset now includes TRMM-era data from June 2000 to the present, and other TRMM-era data has been reprocessed with GPM-era algorithms and is now available on the GPM FTP servers. TMPA data production ended as of December 31st, 2019 and the TRMMOpen FTP server has been shut down. Historical TMPA data is still available to download from the NASA GES DISC at: https://disc.gsfc.nasa.gov/datasets?keywords=TMPA&page=1

Click here for more details on the transition from TMPA to IMERG. 

Am I allowed to use GPM data for my research?

Yes, in line with NASA's general data policy. Please refer to the GPM Data Policy for further details.

How do I give credit for using GPM data?
Where can I find detailed documentation on the precipitation algorithms?

Browse our directory of GPM & TRMM data products to locate your desired algorithm, then click on the links in the algorithm description under "Documentation". All documentation is also available at the Precipitation Processing System website

What is the spatial and temporal resolution of GPM data?

The resolution of Level 0, 1, and 2 data is determined by the footprint size and observation interval of the sensors involved.  Level 3 products are given a grid spacing that is driven by the typical footprint size of the input data sets.

For our popular multi-satellite GPM IMERG data products, the spatial resolution is 0.1° x 0.1° (or roughly 10km x 10km) with a 30 minute temporal resolution.

Visit the directory of GPM & TRMM data products for details on the resolution of each specific products.

Can I use images or videos from this site or other NASA websites?

For questions about permission for using NASA images and videos, please refer to NASA's official Media Usage Guidelines. For any additional questions please contact bert.ulrich@nasa.gov

Is it possible to subset GPM data?

There are several sources for downloading and viewing data which allow you to subset the data to only include specific parameters and/or geographic locations. These include the GES DISCGiovanni and STORM. In Giovanni you can obtain data for a specific country, U.S. state, or watershed by using the "Show Shapes" option in the "Select Region" pane.

What is the difference between "Near Real-time" (NRT) and "Production" / "Research" data?

GPM data products can be divided into two groups (near real-time and production) depending on how soon they are created after the satellite collects the observations. For applications such as weather, flood, and crop forecasting that need precipitation estimates as soon as possible, near real-time data products are most appropriate.  GPM near real-time (GMI & DPR) products are generally available within a few hours of observation.  For all other applications, production data products are generally the best data sets to use because additional or improved inputs are used to increase accuracy.  These other inputs are only made available several days, or in some cases, several months, after the satellite observations are taken, and the production data sets are computed after all data have arrived, making possible a more careful analysis.

For the GPM IMERG dataset, IMERG Early and Late Runs are the near real-time products, while IMERG Final Run is the research / production product. Click here to learn more about the differences between IMERG Early, Late and Final. 

We have discovered that the gauge analysis was erroneously omitted from the "production" 3B42/43 products starting with January 2016 due to issues with handling a change of data format. Thus, the production 3B42/43 are being re-computed. This does not affect the TMPA-RT suite of products, since no month-to-month gauge data are used. Note this issue also affects the current Version 3 IMERG Final Run products for January 2016. They are being recomputed as well. The current Version 3 IMERG Early and Late Runs are not affected. An update will be provided here when the corrected products are ready.
UPDATE 9/27/16: January 2016 IMERG has been regenerated and posted. This was necessary due to an error that omitted the gauge analysis in the Final products. Also, 3B42/3B43 have been recomputed and posted. Let me know if you have any further questions. --- PPS has removed the January 2016 GPM IMERG and January through June 2016 3B42/3B43 TMPA products from our ftp archive: ftp://arthurhou.pps.eosdis.nasa.gov/ and STORM: https://storm.pps.eosdis.nasa.gov/storm/ The GPM science team discovered that the IMERG final products for Jan 2016 and the Jan-Jun 2016 TMPA 3B42/3B43 products for which we...
What: Google Earth access for near-realtime IMERG and 3B42 KML files will be replaced by an updated service for viewing precipitation data in near-real time on a 3D virtual globe using Cesium ( https://cesiumjs.org/ ). When: The current plan is to make the cut-over to the new Cesium-based service on or about October 16, 2016. Why: The evolution of network policies and applications prevents continued GPM use of Google Earth. Note: If you wish to continue using KML files with a non-Google Earth client, please contact the Precipitation Measurement Missions at: https://pmm.nasa.gov/contact
The PPS (Precipitation Processing System) will be down today, September 20,2016 from 8:00am -2:00pm EDT (12:00 - 18:00 UTC). for scheduled maintenance. During this time all data transfers between PPS source and its consumer systems (GDAAC/DISC) as well as Science User services (FTP and STORM access) will be unavailable. You may contact PPS Operations at 301-614-5247 , 301-614-5184 or fax us at 301-614-5269 if there are any urgent matters requiring our immediate attention during this period. You will be informed when PPS systems become available. We apologize for any inconvenience this may...
The PPS (Precipitation Processing System) will be down Sunday September 18, 2016 -estimated time from 10:00am to 6:00pm EDT (14:00 - 22:00 UTC) for Special Unscheduled Maintenance. Please note: although it is unlikely, due to unforeseen events PPS systems might be down overnight and only be available starting Monday morning, September 19, 2016. During this time, all data transfers between PPS source and its consumer systems (GDAAC/DISC) as well as Science User services (FTP and STORM access) will be unavailable. You may e-mail “sysgods@mail.pps.eosdis.nasa.gov” if there are any urgent matters...

Hide Body

Hide Date