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Great Lakes
Article:
Scientists: Minnesota weather to morph
into Kansas—how fast is the question
By Eric Magnuson
www.pulsetc.com
Published November 10, 2005
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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