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Full catalog/GPM_IMERG_LandSeaMask
GPM_IMERG_LandSeaMask·v2·dataset

Land-versus-sea map for rainfall data (IMERG)

Land/Sea static mask relevant to IMERG precipitation 0.1x0.1 degree V2 (GPM_IMERG_LandSeaMask) at GES DISC
atmosphere NASA GES_DISC Level 4 active
In plain English

What it measures. A fixed map marking which grid cells are land and which are sea, matched to the grid used by IMERG rainfall data.

How it's made. Adapted from a 1980s NOAA land-sea mask, restructured by NASA to line up exactly with the IMERG precipitation grid and saved in modern netCDF format.

How & where you'd use it. A helper file used alongside IMERG rainfall products to tell land from ocean. It's static (no seasonal change) and is not recommended for use outside those precipitation products.

What's measured

ATMOSPHERE › PRECIPITATION

Coverage & cadence

  • Time span1998-01-01 → ongoing
  • Measured byIMERG (NOT APPLICABLE)
  • Processing levelLevel 4
  • Spatial extent-180, -90, 180, 90
  • StatusACTIVE

What you can do with it

  • Map air pollutants — NO₂, aerosols, ozone
  • Track greenhouse gases and Earth's energy budget
  • Feed weather and air-quality analysis
Official description

Version 2 is the current version of the data set. Older versions will no longer be available and have been superseded by Version 2. This land sea mask originated from the NOAA group at SSEC in the 1980s. It was originally produced at 1/6 deg resolution, and then regridded for the purposes of GPCP, TMPA, and IMERG precipitation products. NASA code 610.2, Terrestrial Information Systems Laboratory, restructured this land sea mask to match the IMERG grid, and converted the file to CF-compliant netCDF4. Version 2 was created in May, 2019 to resolve detected inaccuracies in coastal regions. Users should be aware that this is a static mask, i.e. there is no seasonal or annual variability, and it is due for update. It is not recommended to be used outside of the aforementioned precipitation data.

Get the data

gpm_imerg_landseamask_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="GPM_IMERG_LandSeaMask",
    version="2",
    bounding_box=(-122.5, 37.2, -121.8, 37.9),  # your area (W,S,E,N)
    temporal=("2024-01-01", "2024-12-31"),       # your dates
)
files = earthaccess.open(results)   # stream straight from GES_DISC
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.