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Scientists: Minnesota to morph into Kansas–how
fast is the question
BY ERIC MAGNUSON
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| White birch trees may disappear in Minnesota
if scientists are correct about climate change. |
Riding in my parent’s SUV as an anxious child in 1985, whining
and wondering when we’d finally arrive at a cabin north of Brainerd
from our Minneapolis suburb, my father tried making the trip easier
by saying we’d be close once we saw a northern Minnesota staple:
white paper birch.
This guide never left me. On future trips to Duluth as an adult, I
knew my destination inched closer when birch trees lined the highway.
But climate change is predicted to move this place-marker.
Some scientists, particularly those who released a study in 2003 titled
“Confronting Climate Change in the Great Lakes Region,”
predict the birch population in northern Minnesota may disappear altogether
by the end of the century. As average temperatures increase from year
to year, Minnesota’s summer climate is expected to become similar
to Kansas, which is more than a few hundred miles south. In a worst
case scenario, Minnesota’s entire vegetation may change by century’s
end. “If it warms up and drys out a little, the prairie-forest
border will push north and east into the state,” says Peter
Wyckoff, associate professor of biology at the University of Minnesota
in Morris. “I don’t think anyone disagrees on that,”
he adds. Some research says Minnesota’s average summer temperatures
will be as much as 16 degrees hotter, possibly in the lifetime of
today’s newborns. The group Minnesotans for an Energy-Efficient
Economy says the state’s summer climate may be similar to Kansas
as soon as 2035.
Global warming is to the world what cholesterol is to the human body:
Slowly, often too slowly for the naked eye to see, it alters the system
it invades, perhaps disrupting it forever. “The boreal forest
will definitely be lost” due to climate change, says Lucinda
Johnson, associate director at the Natural Resources Research Institute
in Duluth. As soils become drier, the prairie will expand throughout
much of Minnesota. “The question is, how fast will that happen?”
Wyckoff asks.
When looking at Minnesota’s vegetation on a map, the prairie
hugs the state’s western border with the Dakotas and slowly
widens in the southwestern corner. Researchers are concerned that
Minnesota’s climate may change too rapidly this century due
to global warming. Trees like the birch are adapted to the state’s
northern climate. If warm climates slowly move northward, birch and
other trees might be able to move along with it. But if it moves too
fast, the tree populations might not be able to regenerate as the
prairie chews into the state. Seasons are expected to change. We’ll
have shorter and warmer winters. Minneapolis may have as many as 25
summer days per year exceeding 97 degrees by century’s end.
With longer summers, Minnesota will have an extended growing season.
“[But] if you take the climate in Kansas and put it in northern
Minnesota, it’s not likely that you’ll also bring the
farming economy,” Johnson says, “The soil in northern
Minnesota is unproductive and rocky.”
Closer to home, “Minneapolis and St. Paul will be particularly
vulnerable because extremely high temperatures are now rare,”
states a Union of Concerned Scientists study. And the Minnesota Pollution
Control Agency mentions another report stating that temperatures 3
degrees warmer could triple heat-related deaths over an average summer
in Minneapolis. Extreme heat causes about 60 deaths per summer in
the city today. Kim Knowlton, of Columbia University, has studied
past heat waves in major cities to predict what may happen in the
future. “Looking at different heat waves in Chicago and Europe,
people over 65 were the most likely to die,” Knowlton says.
The elderly poor and urban poor are less likely to have air conditioning,
putting them at risk during an abnormally hot day. But air conditioning
poses a problem because it also contributes to greenhouse gases in
the atmosphere.
Renowned NASA climatologist James Hansen has a different take on climate
change. “The argument is made that people in the United States
move all the time. They’ll move from Minneapolis to Atlanta
and they can survive in quite a different climate. No doubt, there
are some places where they might prefer a warmer climate,” he
jokes in his office, “But in general, it seems to me that it’s
unlikely to be advantageous.”
The list of effects that climate change may have on Minnesota fill
numerous thick studies. Johnson says we’ll likely experience
more intense storms, causing earlier spring flooding. “Rain
falling on frozen soil is like rain falling on a parking lot,”
pushing runoff and pollution into rivers. Disease-carrying insects
will have a greater chance to live through warmer winters. Lakes will
experience fewer days covered with ice. Climate change speeds a lake’s
life cycle, turning it into a wetland faster than without warming.
The research is less certain on whether the Great Lakes will lose
water. However, it’s calculated that for every inch Lake Michigan
loses, a ship must travel with 90 less metric tons of cargo. This
means they lose at least $22,000 per shipment. These losses generally
get passed to consumers.
The forecast isn’t certain. Many scientists believe worst case
scenarios can be avoided if alternatives to gas guzzling cars become
mainstreamed. “Not only is there going to be pressure from [politicians],”
Hansen says, “but I think a lot of businessmen recognize that
it is do-able to start getting serious about energy efficiency. China
is already putting stricter efficiency standards on vehicles than
the U.S., and if we want to sell vehicles to growing markets and developing
countries, then we better have the technology to do that.”
Wyckoff notes how oaks on the prairie-forest border today are likely
to survive through their normal life cycles. But due to various causes
it’s becoming more difficult to find new trees. His office in
Morris sits near the prairie’s edge. He predicts Minnesota’s
shift from forest to prairie will happen later rather than sooner.
He doesn’t foresee the transition happening within 30 years,
however, if it does, he says with a laugh, he’ll call us in
the Twin Cities to say, “The prairie is coming.”
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