| September 9, 2009 |  |
Iowa’s Climate and Economy to Suffer Significantly if Climate Change Continues Unchecked, Says New Report
Congress Considering Legislation that Could Help Iowa and the Rest of the Nation Avoid Worst Consequences of Global Warming
CHICAGO (Sept. 9, 2009) — If the United States does not significantly curb heat-trapping emissions, global warming will seriously damage Iowa's climate and economy, according to a new peer-reviewed report released today by the Union of Concerned Scientists (UCS). The report also found that a combination of clean energy policies—such as those currently under consideration by the U.S. Senate—would help blunt the extent and severity of global warming in Iowa and across the country.
"The Midwest climate is already changing. Over the past 50 years, we've seen higher average annual temperatures, more frequent downpours, longer growing seasons, and fewer cold snaps," said Don Wuebbles, a climate scientist at the University of Illinois at Urbana-Champaign and a co-author of the report. "The likely changes documented in this report are sobering. The good news is that we can avoid the worst of them if we substantially cut global warming emissions and start doing it now."
The report, "Confronting Climate Change in Iowa," describes how the state's climate could change under two scenarios: one assumes a business-as-usual increase in heat-trapping emissions from continued heavy reliance on fossil fuels, and the other assumes substantially lower emissions due to an increased reliance on clean energy sources. The report compared the two scenarios with a baseline period between 1961 and 1990.
The report found that toward the end of this century, under the higher, business-as-usual emissions scenario:
Climate: Average summer temperatures in Iowa would be as much as 14°F higher than the baseline period. Over that 30-year stretch, Des Moines experienced 22 days per summer when temperatures topped 90°F and about two days with temperatures over 100°F. Unchecked global warming would force city residents to endure more than 85 days every summer with temperatures higher than 90°F and more than a month with temperatures over 100°F.
Des Moines residents also would face at least three heat waves per summer like the one that killed hundreds in Chicago in 1995. According to the Centers for Disease Control and Prevention, heat waves already kill more people in the United States each year than hurricanes, tornadoes, floods and lightning combined.
Agriculture: The agriculture sector would suffer from substantially more heat stress, which would decrease livestock productivity. Iowa hog producers—whose hog sales reached $4.3 billion in 2007—already lose an estimated $40 million annually from heat-stressed animals. By the end of the century, nearly permanent heat stress would plague hogs, dairy cattle, and other livestock unless they are kept cool, for example, in costly air-conditioned barns.
Crop yields also would suffer. Iowa has nearly three-quarters of its land in crop production and ranks third among the states in crop value. A 1988 heat wave that cost the United States $40 billion—mostly due to crop losses—reduced corn and soybean yields in Iowa by more than 75 percent and 80 percent respectively compared with Iowa annual yield averages from 1978 to 1997. Under the higher-emissions scenario, by mid-century all Iowa summers are projected to be hotter than 1988.
Warmer winters and a growing season as much as six weeks longer than that of the baseline years would enable pests, such as the corn earworm, to expand their range. During the 30-year baseline, conditions favorable to the corn earworm occurred only once every three years in Iowa. With unchecked global warming, by the end of the century corn earworm infestations could occur every summer.
Crop production would be threatened by changing rain patterns, ranging from wetter springs—which delay planting and increase flood risk—to nearly 20 percent less rain during increasingly hot summers. Crop-damaging three- and seven-day heat waves would occur at least every other summer toward the end of the century. During the report's baseline period, three-day heat waves occurred only about once a decade, and seven-day heat waves occurred one out of every 30 summers.
Extreme Weather: A 2008 flood in Iowa washed out 20 percent of the state's crops, valued at nearly $4 billion, and levee breaks flooded 1,300 city blocks in Des Moines and Cedar Rapids at the cost of $6,100 per resident. If we fail to cut global warming pollution, heavy rains would become more common throughout the year, leading to a greater incidence of flash flooding. Winters and springs, when the flood risk is already high, would become nearly 30 percent wetter than during the baseline decades.
Health: If tailpipe and smokestack emissions continue at today's levels, Iowa would experience more severe smog as the number of extremely hot days increases. That would have serious consequences for public health, including a greater incidence of asthma attacks and other respiratory conditions. For example, ground-level ozone—the main component of smog—increases at temperatures higher than 90°F. Large cities in Iowa could expect to see many more days of dangerous ozone levels than would occur if global warming emissions were reduced.
In June, 13 federal agencies released a comprehensive national report using the same methodology as the UCS report released today. Like the UCS report, the federal report concluded there is still time to avoid the worst consequences of climate change.
Shortly after the national report came out, the House of Representatives passed "The American Clean Energy and Security Act," a landmark bill that would help build a new clean energy economy and launch the first national plan of action to address global warming. The Senate is currently considering a similar bill.
"The science is clear. We have to get started now so that our children and grandchildren don't suffer from deadly heat waves, and our farmers don't have to battle more extreme droughts and floods, and more pest and weed infestation," said Ron Burke, UCS's Midwest office director. "Our report shows how critical it is for Iowa's congressional delegation to support a bill that will get America running on clean energy."
The Union of Concerned Scientists puts rigorous, independent science to work to solve our planet's most pressing problems. Joining with citizens across the country, we combine technical analysis and effective advocacy to create innovative, practical solutions for a healthy, safe, and sustainable future.
