Publications

Mishra, S; Stumpf, RP; Schaeffer, B; Werdell, PJ; Loftin, KA; Meredith, A (2021). Evaluation of a satellite-based cyanobacteria bloom detection algorithm using field-measured microcystin data. SCIENCE OF THE TOTAL ENVIRONMENT, 774, 145462.

Abstract
Widespread occurrence of cyanobacterial harmful algal blooms (CyanoHABs) and the associated health effects from potential cyanotoxin exposure has led to a need for systematic and frequent screening and monitoring of lakes that are used as recreational and drinking water sources. Remote sensing-based methods are often used for synoptic and frequent monitoring of CyanoHABs. In this study, one such algorithm - a sub-component of the Cyanobacteria Index called the CIcyano, was validated for effectiveness in identifying lakes with toxinproducing blooms in 11 states across the contiguous United States over 11 bloom seasons (2005-2011, 2016-2019). Amatchup data setwas created using satellite data fromMEdiumResolution Imaging Spectrometer (MERIS) and Ocean Land Colour Imager (OLCI), and nearshore, field-measured Microcystins (MCs) data as a proxy of CyanoHAB presence. While the satellite sensors cannot detect toxins, MCs are used as the indicator of health risk, and as a confirmation of cyanoHAB presence. MCs are also the most common laboratory measurement made by managers during CyanoHABs. Algorithm performance was evaluated by its ability to detect CyanoHAB `Presence' or 'Absence', where the bloom is confirmed by the presence of the MCs. With same-day matchups, the overall accuracy of CyanoHAB detection was found to be 84% with precision and recall of 87 and 90% for bloom detection. Overall accuracy was expected to be between 77% and 87% (95% confidence) based on a bootstrapping simulation. These findings demonstrate that CIcyano has utility for synoptic and routine monitoring of potentially toxic cyanoHABs in lakes across the United States. (c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license (http:// creativecommons.org/licenses/ by/4.0/).

DOI:
10.1016/j.scitotenv.2021.145462

ISSN:
0048-9697