Linking year-to-year Cladophora variability in Lake Ontario to the temperature contrast between nearshore and offshore waters during the spring

Images from thermal satellite sensors clearly show the spatial and temporal characteristics of surface temperature distributions during the spring heating period in Lake Ontario. The satellite information combined with summertime beach closure data at Ontario Beach, Rochester, NY, shows that there is a correlation of the percent of summer beach closings caused by accumulation of algae (primarily Cladophora) with the cumulative temperature contrast between nearshore and offshore waters during the spring heating period. The physical conditions created by a rapid warming of the nearshore water during the spring warming period appear to generate conditions favorable to Cladophora growth in the summer. The results of this study suggest that satellite thermal observations of Lake Ontario in the spring can be used to better understand year-to-year variability of Cladophora growth as well as potential reactions to climate change. (C) 2012 International Association for Great Lakes Research. Published by Elsevier B.V. All rights reserved.