Climate change in Michigan: Lower lakes, higher temps

Experts weigh in as international panel's reports show trouble for Great Lakes

Climate change is coming to Michigan and a Great Lake near you, according to a panel of experts convened to discuss recent reports from the Intergovernmental Panel on Climate Change (IPCC).

The panel—including MEC Energy Program Director David Gard—briefed reporters on a conference call following the release of new IPCC data on April 6.

The IPCC reports—being released in stages this spring—are produced by 600 authors from 40 countries and reviewed by more than 620 experts and governments. The IPCC found that global climate change is almost certainly driven by manmade greenhouse gas emissions.

The Michigan experts told reporters that the Michigan and Great Lakes effects of climate change may include:

• Higher temperatures: Temperatures in Michigan have risen by a little less than 2 degrees Fahrenheit since the 1980s and are projected to increase 2 to 7 degrees by the end of the century, according to George Kling, a University of Michigan ecology and evolutionary biology professor. Most warming occurs in winters, in the Upper Peninsula and at nighttime.
• Unpleasant weather: Though fewer people will suffer from cold weather-related injuries or deaths, more will suffer from extreme heat conditions. The number of dangerous heat days may increase by five to 10 times by the end of the century.
• Lower lake levels: Higher temperatures produce less ice cover on the Great Lakes, which means more water evaporates off the lakes. As a result, lake levels are projected to decrease by one to five feet by the end of the century, Kling said.
• Changes in precipitation: Michigan will have more frequent heavy rainstorms, occurring mostly at the beginning of the spring, followed by less rainfall during the summer months.
• Changing agricultural conditions: Since the heavy rainfall will arrive at the beginning of spring when farmers are trying to prepare their fields, crops will not benefit from the increased precipitation. Also, since Michigan summers will feel more like Arkansas summers by the end of the century, crops will react differently to the new climate.
• Lakes trouble: With longer summers, the Great Lakes will experience more “dead zones,” in which no living organisms can survive, affecting water-based industries and anglers alike. Invasive species may spread farther and more quickly.
• Decreased biodiversity: Although it’s not a Great Lake, Scudder Mackey of the University of Windsor calls Lake St. Clair a “sentinel basin.” Mackey’s research suggests the lake could lose up to 20% of its surface water due to climate change. That would move the shoreline into the lake by about three miles, leaving at least 28 critical spawning sites “high and dry.” This is just one example of how global warming will affect the ability of certain species to survive in a changing climate.
• Cherry industry decline: Michigan leads the nation in cherry production. Unlike many crops, cherries depend more on temperature than on water to flourish. Once they come out of dormancy, cherry trees are susceptible to freezing temperatures. Michigan has experienced a higher number of spring freezes recently. Although it’s uncertain whether climate change is responsible for the unusual weather, the situation matches other climate change trends, according to Jeff Andresen, a Michigan State University professor who is also the state’s climatologist.

Globally, the IPCC reports that both the heat-trapping gases carbon dioxide and methane exceeded their natural ranges in 2005. Carbon dioxide reached 379 parts per million (ppm) when its natural range is 180-300 ppm, and methane reached 1,774 parts per billion (ppb) when its natural range is 320-790 ppb. The reasons for these increases are mostly attributed to fossil fuel use, human agricultural activities, and land-use changes.

Eleven of the 12 years from 1995-2006 have ranked among the top 12 warmest years since 1850, according to the IPCC.

Because the IPCC reports are consensus documents, they tend to make conservative estimates say analysts.

For information on the findings, visit www.net.org/warming/ipcc.vtml. To learn how to help slow climate change, visit www.ecofriend.org or www.stopglobalwarming.org.