Evaluating Atmospheric Correction Algorithms for Accurate Water Quality Detection in Lakes Using Landsat: A Comparative Analysis

Inland waterways, including lakes, play a crucial role in sustaining ecosystems, providing drinking water, supporting biodiversity, and generating economic value. However, urbanization and industrialization have contributed to harmful algal blooms (HABs) and the decline of water quality, posing both ecological and economic risks. While traditional in situ monitoring of chlorophyll-a (chl-a), an indicator of HABs, is accurate, it is also labor-intensive and costly. Remote sensing offers a more efficient alternative by providing high-resolution spatial and temporal data. Satellite sensors, such as Landsat and Sentinel, have shown promise in detecting chl-a concentrations, proving to be cost-effective and reliable for large-scale HAB monitoring.

Accurately correcting atmospheric effects in optically complex waters is a significant challenge, especially for high-precision applications like chl-a detection. Technical limitations such as spatial resolution, cloud coverage, and data accuracy hinder the broader use of satellite remote sensing. Furthermore, validating satellite-derived chl-a data requires accurate in situ measurements to minimize error propagation and ensure reliable assessments.

This study leverages recent remote sensing satellite series, including Landsat 8 and 9 data, as well as historical datasets from clear mesotrophic and oligotrophic lakes in the Adirondacks. The effectiveness of various atmospheric correction algorithms is evaluated by comparing satellite-derived chl-a estimates with in situ measurements. Preliminary results reveal significant variations in algorithm performance, particularly in their ability to detect chl-a accurately. While algorithms are sensitive to water color variations on an individual lake scale, stronger correlations between estimated and measured chl-a are observed in larger lakes. These findings emphasize the importance of selecting appropriate atmospheric correction techniques tailored to specific lake characteristics and conditions for accurate chl-a monitoring.