The Great Lakes region is warming faster than the rest of the U.S., a trend likely to bring more extreme storms while also degrading water quality, worsening erosion and posing tougher challenges for farming, scientists reported Thursday.
The annual mean air temperature in the region, which includes portions of the U.S. Midwest , Northeast and southern Canada, rose 1.6 degrees (-16.9 Celsius) from 1901-60 and 1985-2016, according to the report commissioned by the Chicago-based Environmental Law & Policy Center. During the same periods, the mean temperature for the remainder of the contiguous U.S. rose 1.2 degrees (-17.1 Celsius).
Warming is expected to continue this century, with rates depending on the volume of heat-trapping gases such as carbon dioxide and methane that humans pump into the atmosphere. As the air warms, it will hold more moisture, which likely will mean heavier winter snowstorms and spring rains — with more flooding in vulnerable areas. Yet summers will be hotter and drier.
"Over the last two centuries, the Great Lakes have been significantly impacted by human activity, and climate change is now adding more challenges and another layer of stress," said Don Weubbles, an atmospheric scientist at the University of Illinois and former assistant director of the Office of Science and Technology Policy in the Obama administration. "This report paints a stark picture of changes in store for the lake as a result of our changing climate."
Agriculture will be hit especially hard, said the report produced by 18 scientists, most from Midwestern universities as well as the National Oceanic and Atmospheric Administration.
Wetter springs will cause delays in planting, while crops will be more stressed with less water and more heat during summer. The report predicts yield decreases of 10-30 percent for corn and soybeans by the end of the 21st century.
Heavier storms also will boost the danger of erosion for beaches, dunes and shorelines, it said.
Harmful algae blooms are likely to become more numerous and severe as water temperatures warm, and bacteria levels that make waters dangerous for swimming should continue to rise.