Chlorophyll-a concentrations and algal bloom condition paired with Sentinel-2 aquatic reflectance values collected for Brownlee Reservoir, ID from 2015 through 2020

This data release presents two calibration datasets that relate aquatic reflectance derived from Sentinel-2 satellite imagery with algal bloom conditions in the Brownlee Reservoir on the Idaho Oregon border. These datasets were developed to evaluate remote sensing methods for identifying algal blooms in Brownlee Reservoir like those from July 2022 that are illustrated in field photo (left) and satellite imagery (right) in “Picture1.png”. The first calibration dataset includes satellite-based spectra paired with chlorophyll-a concentrations in micrograms per liter analyzed by the Bureau of Reclamation Soil and Water Laboratory with standard method 10200 H.2 on water samples collected within 2 m of the surface by Idaho Power Company staff. The second dataset includes satellite-based spectra paired with bloom condition assigned based on spectral characteristics and spatial patterns present in satellite imagery. These calibration datasets are used to evaluate spectrally based approaches for retrieving algal bloom conditions from satellite imagery in Brownlee Reservoir as a test case to demonstrate the general utility of identifying algal bloom conditions from Sentinel-2 satellite imagery.