Iowa has experienced numerous extreme weather events in the past 20 years that have caused substantial destruction of property, economic loss and disruption of individual and community patterns of life. Extreme events are a part of "normal" climate, but the frequency of these events is changing and Iowa needs to plan for the future.
Climate change is much more complex than simply a rise in temperature as suggested by the term "global warming." Other climate factors - specifically the frequency of extreme precipitation events, rise in humidity, lack of extreme summer heat and length of the growing season - are having much more impact on Iowa than changes in annual average temperature. We need to understand how climate change could affect agriculture, our health, the state's wildlife and our economy.
So, for almost two years, a small group of faculty members from the University of Iowa, Iowa State University and the University of Northern Iowa has been evaluating the effects of climate change on the state. Authorized by the Iowa General Assembly following the disastrous flooding of 2008, the committee has just issued its report.
Farmers have adapted to changing climate by planting earlier, installing more subsurface tiles to drain excess soil water faster, and purchasing larger combine heads to facilitate harvest in the fewer hours without dew. A continuation of this changing climate will impact future production through increased replanting, new pests and diseases, accelerated soil erosion, increased nitrate leaching, and increased challenges associated with timely and efficient application of manure and herbicides.
The global context of agriculture means that we are affected by the changing climate of our trading partners or competitors. In 2010, when unprecedented drought conditions led to vast fires in Russia, wheat and corn crops were decimated and global commodity prices increased dramatically, sending corn prices above $5 per bushel. In this instance, Iowa benefited from Russia's climate extreme, but if climate extremes in the Midwest follow recent trends, Iowa production in some years could fall well below expectations.
Effects of climate change on human health likely will include more allergic rhinitis, asthma and reactions to mold due to continuing trends toward higher humidity. In Iowa's 2008 floods, researchers identified flood-related ailments that left many sick for weeks. Extreme events such as this will challenge our public health practitioners to do more to prepare for these events and to protect us when they occur.
Iowa's animals and plants are responding to climate change. Many species of birds such as the American robin are arriving earlier in the spring, and flowers are blooming earlier. The effects on our game species can't be fully predicted, but cold-water fish - such as trout and small-mouth bass - could be vulnerable. Populations of migratory waterfowl will decline if increasing droughts to our west impair their nesting grounds. On the bright side, consumers and state and local governments already are saving on their heating bills, and farmers have benefited from favorable growing conditions. But a higher frequency of intense storms will increase costs for disaster services and clean up. Roads, bridges, storm sewers, power lines, and culverts under rural roads will need design upgrades to cope with the new normal. Our prominent insurance industry is already responding to increased claims accompanying regional climate trends.
Our recommendations include:
- Fund infrastructure improvements to protect against flooding.
- Protect Iowa's soil, water quality and long-term agricultural productivity in the face of climate change (for example, preserving more marginal lands and restoring wetlands and buffer zones).
- Designate the Iowa Department of Public Health to report annually on the consequences of changing climate on the health of Iowa citizens.
- Authorize the Iowa Insurance Division to report the risks and anticipated costs of property insurance related to climate-related claims.
With this report, the regents institutions stand ready to help Iowa build resiliency to climate change that is already taking place and likely will continue.