New Ice Monitoring Technique Offers Insight into Great Lakes
With winter weather fast approaching, we start to look at how the big chill will affects our economy. And for the Great Lakes, frozen ice is bound to affect shipping lanes and local fishing industries. Connected to the Atlantic Ocean by way of the Great Lakes Waterway, each year, millions of tons of cargo are moved onto the lakes, supplying the US and Canada with important commodities.
In addition to economic impacts, the lakes have a significant effect on the regional environment and ecological systems so the importance of analyzing and observing these frozen waters is crucial for the region.
Fortunately, two scientists from NASA and NOAA have developed a new space-based technique for monitoring the ice cover of the Great Lakes.
"In the dark, it's difficult to read a map that's right in front of you," said Son Nghiem of NASA's Jet Propulsion Laboratory, Pasadena, California, one of the developers of the new technique. "Yet we now have a way to use satellite radars almost 500 miles [800 kilometers] out in space to see through clouds and darkness and map ice across the Great Lakes."
The new method, co-developed by Nghiem and his colleague George Leshkevich of NOAA's Great Lakes Environmental Research Laboratory, Ann Arbor, Michigan, gives a more accurate analysis of ice characteristics, such as whether the ice is dense or full of bubbles, whether it has melted and refrozen, and whether there is snow on top of the lake ice.
The method uses a special dictionary that translates binary digital data from satellite radar instruments on the Canadian Space Agency's RADARSAT-1/2, the European Space Agency's European Remote Sensing Satellite 2 (ERS-2), and Envisat to identify and map different types of ice over the Great Lakes. The researchers compiled the dictionary by pairing each observed ice type to a library of unique radar signatures that were measured on the lakes using a JPL-developed advanced radar aboard a U.S. Coast Guard icebreaking ship.
Leshkevich said, "These maps will provide important information for environmental management, ice forecasting and modeling, off-shore wind farm development, operational icebreaking activities in support of winter navigation, and science research."
This ice classification will also provide insight as to how the Great Lakes are responding to, and leading, climate change in the upper Midwest.
Results of the study were published recently in the Journal of Great Lakes Research.
Read more at NASA's Jet Propulsion Laboratory.
Great Lakes image via Wikipedia.