Can we predict the years when algae will stink up our beaches?

Ann Arbor, MI — The enjoyment of Lake Ontario beaches on a warm summer day is frequently tempered by the stink of decaying algae that washes up on shore. The culprit is often the bottom-growing algae called Cladophora. A number of recent scientific studies have helped us understand how nutrient cycling pathways have contributed to a resurgence in Cladophora growth in Lake Ontario, however these studies don’t entirely explain why some years have a big algae problem and some years don't. This study was designed to help address this question of year-to-year variation in algae growth by focusing on the role of water temperature rather than nutrients as a driving force.

Cladophora grows in response to nutrients, light, and warm water temperature. The hypothesis of this study is that year-to-year differences in how Lake Ontario warms up in the springtime has an influence on how well Cladophora grows during the summer and how much eventually winds up on the beaches. Testing this hypothesis requires measurements of water temperature change during the spring and algae accumulation during the summer. The NOAA CoastWatch Great Lake Node features the Great Lakes Surface Environmental Analysis (GLSEA) daily estimates of lake surface temperature, which are based on satellite thermal imaging sensors. Algae accumulation at Ontario Beach in Rochester, NY USA has been measured for many years by the Monroe County Health Department.

The results of this study did find a statistically significant relationship between springtime water temperature changes in Lake Ontario and the amount of algae accumulating at Ontario Beach later in the summer in the years 2000 to 2010. This result supports the hypothesis that year-to-year variation in lake heating behavior does impact Cladophora growth. The natural next step in this research is to add information on light availability by way of remote sensing of water turbidity (the cloudiness of water caused by suspended particles).

Original Publication Information

Results of this study, "Linking year-to-year Cladophora variability in Lake Ontario to the temperature contrast between nearshore and offshore waters during the spring," are reported by Dr. Anthony Vodacek in the special issue on Lake Ontario, of the Journal of Great Lakes Research, published by Elsevier, 2012.

Contacts

For more information about the study, contact Dr. Anthony Vodacek, Digital Imaging and Remote Sensing Laboratory, Center for Imaging Science, Rochester Institute of Technology, 54 Lomb Memorial Dr, Rochester, NY 14623; vodacek@cis.rit.edu, (585) 475-7816.