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Full catalog/MOD44W
MOD44W·v061·dataset

Map of where land and water are (Terra, 250 m)

MODIS/Terra Land Water Mask Derived from MODIS and SRTM L3 Global 250m SIN Grid V061
land NASA LPCLOUD Level 3 active HDF-EOS2
In plain English

What it measures. A global map at 250 meter resolution showing which parts of Earth's surface are land and which are water, including a seven-category breakdown (shallow ocean, inland water, shoreline, seasonal water, and more) and a quality layer.

How it's made. Built each year from Terra MODIS satellite imagery combined with elevation data, sorted by a decision-tree classifier with corrections for shadows, burn scars, clouds, and ice.

How & where you'd use it. Used to track where land and water meet and how water bodies grow and shrink over time, supporting flood, drought, and water-resource studies.

What's measured

LAND SURFACE › SURFACE RADIATIVE PROPERTIES › REFLECTANCETERRESTRIAL HYDROSPHERE › SURFACE WATER › SURFACE WATER PROCESSES/MEASUREMENTS › TOTAL SURFACE WATER

Coverage & cadence

  • Time span2000-01-01 → ongoing
  • Measured byTerra (MODIS)
  • Processing levelLevel 3
  • Spatial extent-180, -90, 180, 90
  • FormatsHDF-EOS2
  • StatusACTIVE

What you can do with it

  • Track deforestation, fire scars and land-cover change
  • Monitor crop and vegetation health (NDVI/EVI)
  • Map how built-up vs. green an area is over time
Official description

The Terra Moderate Resolution Imaging Spectroradiometer (MODIS) Land Water Mask (MOD44W) Version 6.1 data product provides a global map of surface water at 250 meter (m) spatial resolution. The data are available annually from 2000 to present. MOD44W Version 6.1 is derived using a decision tree classifier trained with MODIS data and validated with the Version 5 MOD44W data product. A series of masks are applied to address known issues caused by terrain shadow, burn scars, cloudiness, or ice cover in oceans. Version 6.1 is the generation of a time series rather than a simple static representation of water, given that water bodies fluctuate in size and location over time due to both natural and anthropogenic causes. Provided in each MOD44W Version 6.1 Hierarchical Data Format 4 (HDF4) file are layers for land water mask and water body classification. A quality assurance (QA) layer provides users with information on the determination of water. The new seven class water classification layer provides values for shallow ocean, land, shoreline, inland water, ephemeral water, deep inland water, moderate ocean, deep ocean, and a classification deemed to fall outside of the projection. Known Issues * The seven_class SDS layer legend for classes 4 and 5 are [incorrectly listed](https://landweb.modaps.eosdis.nasa.gov/displayissue?id=208) as Deep Inland Water and Ephemeral Water in the data for the entire mission period. Users are requested to follow the legend provided in the User Guide. * For complete information about known issues please refer to the [MODIS/VIIRS Land Quality Assessment website](https://landweb.modaps.eosdis.nasa.gov/knownissue?sensor=MODIS&sat=Terra&as=61).

Get the data

mod44w_access.py
import earthaccess
earthaccess.login(strategy="netrc")          # free Earthdata Login

results = earthaccess.search_data(
    short_name="MOD44W",
    version="061",
    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 LPCLOUD
Browsing CMR needs no login. Downloading or streaming bytes needs a free Earthdata Login + the earthaccess package.