This layer maps the intensity of algal blooms over water surfaces using the Maximum Chlorophyll Index (MCI), a proxy for the chlorophyll fluorescence peak that rises with high algal concentrations. It is derived from Sentinel-2 Surface Reflectance imagery (ESA/Copernicus) at 20 m native resolution, restricted to water pixels. Values run from blue (no bloom) through white (baseline) to yellow, orange and red as bloom intensity increases; higher MCI means a more intense bloom.
The layer quantifies algal bloom intensity from the Maximum Chlorophyll Index (MCI), a line-height index that measures the chlorophyll fluorescence peak near 705 nm above a baseline drawn between 665 nm and 740 nm. MCI is more sensitive than NDCI at high chlorophyll-a, which makes it suited to detecting intense blooms.
| Code | Provider | Resolution | Year |
|---|---|---|---|
| WRD_S2XXX_99 | ESA/Copernicus (Sentinel-2 SR Harmonized) | 20 m | 2017-present |
From the Google Earth Engine collection COPERNICUS/S2_SR_HARMONIZED, images over the polygon and requested date range are cloud/shadow masked via the SCL band and restricted to water pixels (SCL class 6). For each image MCI = B5 − B4 − 0.389·(B6 − B4), where B4 is Red (665 nm), B5 Red Edge 1 (705 nm) and B6 Red Edge 2 (740 nm); the 0.389 coefficient follows MERIS heritage (Gower et al., 2005). A temporal mean composite is rendered, and per-geometry min/mean/max MCI are computed after clipping to the display range.