IMERG#

The GPM is next-generation of the Tropical Rainfall Measuring Mission (TRMM - https://pmm.nasa.gov/TRMM). Like the TRMM, the GPM mission aims at providing uniformly calibrated precipitation estimates at a quasi-global scale by merging the measurements from its constellation of microwave and IR satellites. All GPM data sets including measurements obtained from each platform (Level 2) are available on the PMM site (https://pmm.nasa.gov/data-access). Among many GPM products, the Multi-satellitE Retrievals for GPM (IMERG) is most interesting to the users since it delivers the ‘best’ precipitation estimates by combining data obtained from all available microwave and infrared (IR) platforms of the GPM satellite constellation.

IMERG is adjusted to GPCP monthly climatology zonally to achieve a bias profile that is considered reasonable. Multiple runs for different user requirements for latency and accuracy.

  1. “Early” – 4 hour (example application: flash flooding)

  2. “Late” – 14 hour (crop forecasting)

  3. “Final” – 3 months (research)

List datasets

Historical

Timestep

Release

Period

Unit

Link

Monthly

Final Run

Jun 2000 - Sep 2021

mm/month

https://gpm1.gesdisc.eosdis.nasa.gov/data/GPM_L3/GPM_3IMERGM.06/

Daily

Final Run

1 Jun 2000 - 30 Sep 2021

mm/day

https://gpm1.gesdisc.eosdis.nasa.gov/data/GPM_L3/GPM_3IMERGDF.06/

Daily

Early Run

1 Jun 2000 - now

mm/day

https://gpm1.gesdisc.eosdis.nasa.gov/data/GPM_L3/GPM_3IMERGDE.06/

Daily

Late Run

1 Jun 2000 - now

mm/day

https://gpm1.gesdisc.eosdis.nasa.gov/data/GPM_L3/GPM_3IMERGDL.06/

Near-real time

Timestep

Release

Period

Unit

Link

30-minutes

Final Run

1 Jun 2000 - 30 Sep 2021

mm/hour

https://gpm1.gesdisc.eosdis.nasa.gov/data/GPM_L3/GPM_3IMERGHH.06/

30-minutes

Early Run

1 Jun 2000 - now

mm/hour

https://gpm1.gesdisc.eosdis.nasa.gov/data/GPM_L3/GPM_3IMERGHHE.06/

30-minutes

Late Run

1 Jun 2000 - now

mm/hour

https://gpm1.gesdisc.eosdis.nasa.gov/data/GPM_L3/GPM_3IMERGHHL.06/

About the data

Characteristic

Description

Function

Displays hourly, daily and monthly precipitation data

Variable

Total precipitation

Geographic coverage

Global 60N-60S, 180W-180E

Spatial resolution

0.1 degree ~ 11.1 km at equator

Temporal resolution

30 minutes, daily and monthly

Format

NetCDF

Unit

Total mm for given time step, mm/hour, mm/day, and mm/month.

Reference

https://pmm.gsfc.nasa.gov/GPM

imerg

Data access

IMERG daily data available at DEC S3: s3://wbgdecinternal-ntl/climate/data/imerg.