Oct. 3, 2013


The importance of the development of algorithms to monitor ice cover on the Great Lakes

Ann Arbor, MI — As the Great Lakes are the world’s largest freshwater surface, ice cover on the lakes is inherently a large-scale seasonal transformation. Great Lakes ice cover is important to be monitored for many reasons. Its seasonal change has a profound impact on regional environment, ecology, economics, navigation, and public safety. For example, ice arches are naturally formed structures that stop ice from entering into a river. However, when large thick pieces of ice break up, they can destroy the ice arch and cause ice jams, which may trigger winter flooding. Additionally, ice volume and extent controls heat fluxes and evaporation, which affect regional weather patterns, such as lake effect snow. Large amounts of snowfall can cause huge economic losses and pose a hazard to the public. Furthermore, ice cover plays a vital role in aquatic ecosystems. The amount and type of snow-covered ice and its duration determines the amount of light available to algae, influences seasonal algal mass, protects fish spawning beds from winter storms, and thus the recruitment of some fish species (e.g., whitefish). Ice cover is also a sensitive indicator of regional climate change. By observing changes in ice seasons, scientists have found the trend in recent years of less ice cover together with earlier and warmer springs in the Midwest region.

George Leshkevich and Son Nghiem realize the importance of monitoring ice cover on the Great Lakes and have developed algorithms to help categorize and map ice cover on the Great Lakes. By using the Jet Propulsion Laboratory C-band scattermeter, they were able to gather a data set of the radar backscatter signatures from different ice types together with ice physical characterization measurements and environmental parameters to make a unique library for ice classification. Algorithms were developed using European Remote Sensing Satellite 2 (ERS-2) and RADARSAT ScanSAR single and multi-polarization radar images for both small and large incident angles to map ice types and distribution on the Great Lakes. These algorithms and ice maps will provide important information for environmental management, ice forecasting and modeling, operational ice breaking activities in support of winter navigation, and climate change research.

Original Publication Information

Results of this study, "Great Lakes ice classification using satellite C-band SAR multi-polarization data" are reported by George Leshkevich and Son V. Nghiem in Volume 39, Supplemental Issue on Remote Sensing, of the Journal of Great Lakes Research, published by Elsevier, 2013.


For more information about the study, contact George Leshkevich, NOAA Great Lakes Environmental Research Laboratory, 4840 South State Road, Ann Arbor, MI 48108, U;; (734) 741-2265

For information about the Journal of Great Lakes Research, contact Stephanie Guildford, Scientific Co-Editor, Large Lakes Observatory, University Minnesota Duluth, 2205 East Fifth Street, Duluth, Minnesota, 55812-2401;; (218) 726-8064.

Since 1967, IAGLR has served as the focal point for compiling and disseminating multidisciplinary knowledge on North America's Laurentian Great Lakes and other large lakes of the world and their watersheds. In part, IAGLR communicates this knowledge through publication of the Journal of Great Lakes Research, available to members in print and electronic form. A searchable archive of the journal is available online and includes the abstracts of articles from the journal's inception in 1975 through the most recent issue. In addition, complete articles are available to members who have signed up for an electronic subscription.