Des Moines Register: Iowa View--More Extremes Seen as Climate Changes

Monday, July 2, 2012

By Greg Carmichael, UI Karl Kammermeyer Professor of Chemical and Biochemical Engineering and co-director of the Center for Global and Regional Environmental Research and Donald Wuebbles, Professor of Atmospheric Sciences and Electrical and Computer Engineering at the University of Illinois-Urbana/Champaign.

Summer 2012 is barely a week old, but already Iowans are wondering if we’re headed for a record setting season. Temperatures in Des Moines have flirted with 1934’s record of 102 degrees. It’s been a hot start to 2012.

According to the National Oceanic and Atmospheric Administration (NOAA), the period of January to May was the warmest on record for Iowa, Illinois, Wisconsin, Michigan, Indiana, Ohio and Nebraska. Minnesota and Pennsylvania ranked “much above normal.”

The notable anomalies began in March when more than 15,000 warm weather records across our country were broken. Iowa had its warmest March in recorded history, as locals stashed away winter coats and pulled on shorts.

Other areas of our state endured some of the earliest tornadoes on record. Nationwide, NOAA received 223 reports of tornadoes when 80 is the March norm. A string of early March tornadoes across Ohio and the Southeast caused $1.5 billion worth of damage.

Many people are asking the same question: As the climate changes, can we expect more of this? The answer: Yes.

There is a strong probability that climate change is influencing extreme weather events — heat waves, drought and floods.

That’s what we know. We’re not alone. Insurance industry leaders think so, too, and they have been meeting with U.S. senators to call for action.

The extreme weather events with huge costs thus far in 2012 unfortunately reflect a growing recent trend. In 2008, 2010 and 2011, there were 100- or 500-year floods in Iowa, Missouri and Wisconsin. In April 2011, the nation suffered through 875 tornadoes; the previous one-month record was 542.

As the climate changes, the normal cycles of our Earth become altered. Whether from human-related or natural causes, the shifts in temperature associated with the changing climate can change the amount of water vapor in the atmosphere, and this can lead to major changes in the probability for extreme weather. Some evidence can be found by looking at the ratio of extreme highs and lows in U.S. weather over the last 50 years.

In the 1950s, our country had about the same number of extreme heat events as it did extreme cold. That is, the probability of an extraordinarily cold January day was as likely as an excessively hot July day. By the 2000s, however, we were twice as likely to see an extreme high in our weather report as we were an extreme low.

Scientific models are starting to suggest that disasters like the 2010 Russian heat wave, which took 50,000 lives and ruined billions of dollars of wheat crops, were likely related to human-induced climate change. Recent studies have also shown that the salinity and acidity of our oceans are changing, indicating major changes in the Earth’s hydrologic cycle.

As we understand more about the processes affecting climate, our understanding of the Earth’s complex cycles become more nuanced. The evidence is rapidly mounting that we are living in a changing world where climate change is affecting our weather, sometimes in extreme ways.

Fortunately, there are steps we can take to adapt to and mitigate climate change.

We can grow America’s investments in renewable energy, powering more homes with wind and solar energy. We can advance energy efficiency policies and use better appliances and equipment that avoid wasting energy and save us money on utility bills. We can drive more fuel-efficient cars that save us money, lessen America’s dependence on oil, and reduce greenhouse gas pollution. We can build a Midwest high-speed passenger rail system that improves mobility, reduces pollution, creates jobs and pulls together the regional economy. We can improve infrastructure that makes trains and other public transit work better and make bicycle riding a safer option for commuters.

We should educate ourselves about the current state of climate science. We can use one of the pressing issues of our lives as an opportunity for frank dialogue about the ways for people to work together to ensure the Earth’s productivity now and for generations to come.