MODIS/Terra Land Water Mask Derived from MODIS and SRTM L3 Global 250m SIN Grid V006

The MOD44W Version 6 data product was decommissioned on July 18, 2024. Users are encouraged to use the MOD44W Version 6.1 data product.

The Terra Moderate Resolution Imaging Spectroradiometer (MODIS) Land Water Mask (MOD44W) Version 6 data product provides a global map of surface water at 250 meter (m) spatial resolution. The data are available annually from 2000 to 2015. MOD44W Version 6 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. A primary improvement in Version 6 is the generation of time series data 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 Hierarchical Data Format 4 (HDF4) file are layers for land, water, no data, and an associated per pixel quality assurance (QA) layer that provides users with information on the determination of water.

Known Issues * The mask area for pixels outside of the Sinusoidal Grid for tile h27v14 should be labeled as 250 (Outside of Projection) instead of 0 (Land) and the QA values should be 10 (Fill) instead of 3 (Lower confidence land) for years 2000 through 2015. * Additional known issues are described in the User Guide and ATBD. * For complete information about known issues please refer to the MODIS/VIIRS Land Quality Assessment website.