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Full catalog/NISAR_WATERMASK
NISAR_WATERMASK·v1·dataset

Map of where water sits on the surface (NISAR radar)

Derived Water Mask Tiles used by the NASA-ISRO Synthetic Aperture Radar (NISAR) Mission
hydrosphere NASA ASF Level 3 active GeoTIFFXML
In plain English

What it measures. Map tiles marking where surface water sits on the landscape, used as a reference layer for the NISAR radar mission.

How it's made. Created at NASA's Jet Propulsion Laboratory by combining several existing open datasets of surface water, land cover, and ice rather than from a single new sensor.

How & where you'd use it. Serves as a supporting reference for processing NISAR radar products; most people would encounter it via those products rather than use it directly.

What's measured

TERRESTRIAL HYDROSPHERE › SURFACE WATER › SURFACE WATER PROCESSES/MEASUREMENTS

Coverage & cadence

  • Time span2025-01-01 → ongoing
  • Measured byMulti-sensor Analysis
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsGeoTIFF, XML
  • StatusACTIVE

What you can do with it

  • Follow rainfall, floods and surface-water extent
  • Track soil moisture and the onset of drought
  • Monitor lakes, rivers and groundwater storage
Official description

Collection of water mask tiles derived through analysis and processing of multiple input datasets, referenced to the WGS84 ellipsoid used for creation of products from the NISAR mission. Water mask derived at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA, using multiple open datasets: JRC Global Surface Water v1.3 (Pekel et al 2016, Nature 540, 418-422, © EC JRC/Google); ESA WorldCover 10 m 2020 (© ESA WorldCover project 2020 / Contains modified Copernicus Sentinel data (2020) processed by ESA WorldCover consortium); OpenStreetMap Water Polygons (© OpenStreetMap contributors, ODbL 1.0); MEaSUREs GIMP Mask v1 (Howat 2017, doi:10.5067/B8X58MQBFUPA; Howat et al 2014). All trademarks and rights remain with their respective owners; NISAR mission organizations assume no liability for use of this product.

Get the data

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

results = earthaccess.search_data(
    short_name="NISAR_WATERMASK",
    version="1",
    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 ASF
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.