[In this series, BNA’s climate blog takes a closer look at U.S. regions covered in the draft National Climate Assessment. In addition to the Midwest, regions covered in the assessment include the Northeast, Southeast and Caribbean, Great Plains, Southwest, Northwest, Alaska and the Arctic, and Hawaii and U.S. Affiliated Pacific States.]

While the Midwest emits 22 percent more greenhouse gas emissions than the national average, it’s also poised to be a leader in clean energy development, according to the draft National Climate Assessment.

“Compared to other regions, the Midwest has huge potential to produce energy from zero- and low-carbon sources, given its vast wind, solar, and biomass resources,” according to the draft assessment released by a federal advisory committee Jan. 11.

As detailed in an Energy and Climate Report articlepublished Jan. 11, the draft, released by the National Climate Assessment and Development Advisory Committee, is not yet an official federal document. It will become so once it’s submitted to the National Science and Technology Council sometime this fall. The council is expected to review, modify, and approve a final draft by Jan. 30, 2014.

A national assessment on climate science and climate change impacts is due to Congress every four years under the Global Change Research Act of 1990. However, only two reports have been completed since the law passed, one in 2000 and the other in 2009.

The Midwest in the draft national assessment includes Indiana, Illinois, Iowa, Michigan, Minnesota, Missouri, Ohio, and Wisconsin.

Temperature, Precipitation, Great Lakes

Temperatures in the Midwest in the next few decades are expected to rise 3.8 degrees Fahrenheit if greenhouse gas emissions decrease substantially and by 4.9 degrees Fahrenheit under current emission trends, according to the draft.

In comparison, the draft assessment estimates that, on average, U.S. temperatures will rise between 2 and 4 degrees Fahrenheit by mid-century.

In addition to increasing public health risks, higher temperatures also are expected to reduce crop yields in the long-run, the draft said. In the short-run, however, longer growing seasons and the fertilization effect of higher carbon dioxide levels will increase yields. But gains likely will be offset, for example, by earlier spring thaws due to higher temperatures followed by cold snaps that will result in crop damage, the draft assessment said.

An increase in heat waves, especially ones that occur during the pollination of corn and soybean, which account for 85 percent of Midwest crop receipts, also are expected to reduce yields.

Changes in precipitation in the Midwest due to climate change appear to be far less certain. According to the draft, if greenhouse gas emissions remain at high levels, annual rainfall will range from “little change” to a greater than 10 percent increase in the north. In the southern part of the region, models project precipitation may decrease or increase by more than 10 percent, the draft said.

While the region’s precipitation may decrease, the draft said, the number of intense heavy rainfall events, which are projected to continue into the future, will make the region more vulnerable to floods.

The draft assessment highlights a once-in-500-year flood that occurred in June 2008 in Cedar Rapids, Iowa, causing $5 to $6 billion in damage at a cost of about $40,000 per resident. As part of the city’s recovery, funding from the federal and state government allowed the city to buy out more than 1,000 properties in the floodplain and implement building flood protection measures.

The Great Lakes, which provide drinking water to more than 40 million people and have more than 500 beaches, also are expected to remain vulnerable to surface runoff as urban areas expand, reducing infiltration of water into the soil, the draft assessment said.

Climate change also is expected to exacerbate a range of risks the Great Lakes already face, including changes in the range and distribution of commercial and recreational fish species, increased invasive species, declining beach health, and harmful algae blooms.

Decline in ice cover likely will continue to lengthen the commercial navigation season on the Great Lakes, which has increased an average of 8 days since 1994, the draft said. However increasing shipping could increase shoreline “scouring” and bring in more invasive species.

As for water levels of the Great Lakes, the draft said uncertainties remain high, with most models suggesting that a continuing decrease in ice cover will lead to “slightly lower water levels, beyond natural fluctuations.”

Energy Intensive Economy

The Midwest, because of its reliance on coal for electricity generation, also faces greater challenges due to climate change compared to others regions, in part because of an aging, less reliable power grid that will require “significant reinvestment,” even without taking climate change into account. Furthermore, the region is expected to demand more electricity for cooling as more frequent heat waves and higher humidity days occur.

The draft assessment said by mid-century, the demand for cooling is projected to exceed 10 gigawatts, which is equivalent to about five large power plants.
However, the Midwest has been demonstrating progress toward a “decarbonized energy mix,” the draft assessment found.

For example, as of 2012, the region had 25 percent of installed U.S. wind energy capacity, one-third of biodiesel capacity, and over two-thirds of ethanol production, the draft said. The Midwest also shows promise for carbon sequestration.

However, progress in these areas is being hampered, the draft said, by energy prices that are being distorted through a “mix of direct and indirect subsidies and unaccounted-for costs.”
Other uncertainties in the energy sector remain, including the effect Environmental Protection Agency regulations for greenhouse gas will have on power plants and whether the price of natural gas will remain low.

Nonetheless, the draft assessment said there is “very high” confidence in the Midwest’s potential for lower-carbon electricity production.