Kayakers Circumnavigate Lake Superior
By Dave Freeman
Published October 8, 2006
As I write this, the usual sound of waves crashing on
shore is accompanied by the drone of a coal powered paper
mill near Ontanagon, Michigan. As we paddle through more
populated areas we are encountering more and more industry,
which contrasts sharply with our simple daily rituals
or hauling water from the lake, gathering firewood, and
using our own muscles to slowly propel ourselves around
Lake Superior. Last week students told us that they were
interested in learning about the effects global warming
will have on the Great Lakes, which caused us to do some
research and contemplate the issue as we paddle.
When the winds are strong, and our muscles are tired
the thought of adding little motors to the back of our
kayaks is tempting, but learning about climate change
has emphasized the importance of traveling under our own
power. Experiencing Lake Superior by kayak has humbled
us in many ways, and it saddens me to think that the Great
Lakes may be drastically altered by climate change. Hopefully
some of the information we have gathered will make you
think again about global warming and how it may affect
The earth's climate has gone through many cycles of cooling
and warming over time, as indicated by geologic and fossil
records, but scientists are finding that humans are causing
a more rapid change by adding "greenhouse gases"
into the earth's atmosphere. These gases trap heat, like
glass does in a greenhouse, and are making the earth warmer
than it would normally be. Carbon dioxide, the most prevalent
greenhouse gas, is produced by the combustion of fossil
fuels and the clearing and burning of forests.
This unnatural warming could cause water temperatures
of the Great Lakes to increase due to warmer summer air
temperatures and more ice-free time. Warmer water temperatures
could harm water quality by decreasing oxygen in the water
and increasing the growth of algae. The warmer waters
would also decrease habitat for cold water-loving fish
like lake trout and whitefish. Several other kinds of
trout and salmon would also experience habitat losses.
We have seen a lot of commercial fishing during our travels,
and I have to wonder how this would affect the commercial
and sport fishing in Lake Superior.
A warmer climate would cause increased evapotranspiration
(water lost to the atmosphere by evaporation and transpiration).
This could mean a decrease in summer streamflows, causing
reduced water quality. The flow of freshwater into the
Great Lakes could decrease by 20 percent with a warming
of 4 F. A decrease like this could result in a reduction
of lake levels by a foot or more.
You may have heard that global warming will cause the
polar ice caps to melt, resulting in the oceans rising.
The opposite would be the case for the Great Lakes. It
is predicted that Great Lake levels may decrease from
2-5 or more feet as climate change worsens. Lower lake
levels would reduce inputs to hydroelectric power facilities,
increase the concentration of water pollutants, and require
more dredging to maintain ship channels.
Those are just a few of the changes that are possible
in the Great Lakes region if global climate change continues
at its present rate. With all those changes, just think
about the effect on the plants and animals of the region.
What You Can Do
The following is a list of things you can do to reduce
carbon dioxide emissions, so you can do your part to slow
global climate change. This list as well as information
in this Notes From the Trail came from an article (provided
by Gregg Bruff of Pictured Rocks National Lakeshore) called
Climate Change: What Does the Future Hold for Great Lakes
- Walk, use mass transit, carpool with friends, or ride
a bike whenever possible.
- When it is time to replace the family vehicle, consider
one that gets more miles per gallon than your present
- Convert home and office lighting to compact fluorescent
bulbs. Turn off lights you are not using.
- Buy products that feature reusable, recyclable, or
reduced packaging to save the energy required to manufacture
new containers and reduce greenhouse gas emissions from
- Educate others. Let friends and family know about these
practical, energy-saving steps they can take to save money
while protecting the environment.
- Encourage scientific research and public discussion
on global warming and solutions such as energy efficiency
and alternative energy.