Terra MODIS Annual Water Mask data from MOD44W v6.1 over Lake Superior and surrounding areas for 2022.
View full-size imageThe 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.
| Characteristic | Description |
|---|---|
| Collection | Terra MODIS |
| DOI | 10.5067/MODIS/MOD44W.061 |
| File Size | ~2.5 MB |
| Temporal Resolution | Yearly |
| Temporal Extent | 2000-01-01 to Present |
| Spatial Extent | Global |
| Coordinate System | Sinusoidal |
| Datum | N/A |
| File Format | HDF-EOS |
| Geographic Dimensions | 1200 km x 1200 km |
| Characteristic | Description |
|---|---|
| Number of Science Dataset (SDS) Layers | 3 |
| Columns/Rows | 4800 x 4800 |
| Pixel Size | 250 m |
| SDS Name | Description | Units | Data Type | Fill Value | No Data Value | Valid Range | Scale Factor |
|---|---|---|---|---|---|---|---|
| Water_mask | Land/Water Mask | N/A | 8-bit unsigned integer | 250 | 253 | 0 to 1 | N/A |
| Seven_class | Water Body Classification Layer | N/A | 8-bit unsigned integer | 250 | 253 | 0 to 7 | N/A |
| Water_mask_QA | Quality Assurance (QA) | N/A | 8-bit unsigned integer | 10 | 253 | 1 to 9 | N/A |
| Class | Description |
|---|---|
| 0 | Land |
| 1 | Water |
| 250 | Outside of Projection |
| Class | Description |
|---|---|
| 0 | Shallow ocean |
| 1 | Land |
| 2 | Shoreline |
| 3 | Inland water |
| 4 | Ephemeral water |
| 5 | Deep Inland water |
| 6 | Moderate ocean |
| 7 | Deep ocean |
| 250 | Outside of Projection |
| Class | Description |
|---|---|
| 1 | High Confidence Observation |
| 2 | Low Confidence Water |
| 3 | Low Confidence Land |
| 4 | Ocean Mask |
| 5 | Ocean Mask but no water detected |
| 6 | Burned Scar (from MCD64A1) |
| 7 | Urban/impervious Surface |
| 8 | No water detected, Collection 5 shows water |
| 9 | Model predicted water, DEM slope indicates no water |
| 10 | Fill (outside of projected area) |
Quality information is provided in the Water Mask QA layer. Additional product quality information is provided in the product quality description section of the User Guide and Algorithm Theoretical Basis Document (ATBD).
The seven_class SDS layer legend for classes 4 and 5 are incorrectly listed 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 or the Water Body Classification Values table above.