This layer classifies how surface water bodies have changed over the observation record, distinguishing permanent water, seasonal water, and areas that were newly gained or lost. It is derived from the JRC Global Surface Water dataset (Pekel et al.), built from the full Landsat archive at 30 m native resolution. Each pixel is assigned a transition class describing the shift in water seasonality, so stable water surfaces can be told apart from areas of appearance, disappearance, or conversion between permanent and seasonal regimes.
The Surface Water Transition layer shows how the presence and seasonality of surface water have changed across the observation period. It is produced from the transition band of the JRC Global Surface Water dataset, a global map of water dynamics derived from the full Landsat 5, 7 and 8 archive at 30 m resolution.
| Code | Provider | Resolution | Year |
|---|---|---|---|
| JRC/GSW1_4/GlobalSurfaceWater (transition band) | JRC / European Commission | 30 m | 1984-2021 |
For the site polygon the reader retrieves the JRC Global Surface Water transition band and reads its per-pixel transition class, which contrasts water presence at the start and end of the record. Classes distinguish stable permanent and seasonal water from newly gained, lost, and converted water (for example seasonal-to-permanent or permanent-to-seasonal), allowing changes in water extent and seasonality to be mapped over the area of interest.