Note- Image used without permission from: Dan Charles. As drought kills corn, farmers fight over ethanol. NPR, The Salt (blog). 19 Jul 2012. Available at http://www.npr.org/blogs/thesalt/2012/07/19/157044950/as-drought-kills-corn-farmers-fight-over-ethanol (Accessed 24 Nov 2012).
Here is my pragmatic interpretation of climate change’s effect on the Midwestern U.S. in our generation (whether or not you think that climate change is man-made, it’s happening).
Justifiable based on current information
Currently, extreme weather is generally resulting in increased diversion of state and federal funds to FEMA and state disaster relief contingency funds, if not being be offset to taxpayers . Increasing frequency of extreme weather is increasing costs of homeowner’s insurance, and the trend is expected to continue. The insurance industry is expecting increasing costs to beneficiaries, and increasing rates of properties being declared uninsurable due to risk, with a shift of responsibilities to governments . Increasing frequency of extreme weather increases government funds’ diversion, and decreasing insurance willingness to coverage leads to increased government coverage of private citizen’s loss. Given the ongoing dead-lock in the U.S. legislature and the resulting lack of budget reform, it is not a extreme conclusion that one-time bills such as H.R. 152 Disaster Appropriations Act of 2013, if repeated as new environmental crises occur, lead to less funds for social services. 
Temperature shifts and changes in precipitation will lead to decreased ability to irrigate , decreased winter die-off of agricultural pest insects , and limited waterway transport of goods (lack of meltwater to maintain river depth) . Job prospects fall (farming or agriculture support industries) in agricultural rural areas as crop yields fall. Peak yields for corn and soybeans occur first in North/South Dakota, Idaho, Montana, then shift northward into Canada .
The younger generations will be unable to afford remaining in rural towns, and leave to Midwestern cities. Midwestern cities first increase in population and revenue with exodus from rural regions, and then those that don’t have diverse business outside of agriculture start to struggle, causing another exodus. The second exodus decreases cities/states’ taxable base. Those Midwestern states/cities that refuse to raise taxes first make cuts to services, increasing exodus, or go bankrupt, and increase the exodus further. Those Midwestern states/cities who do increase taxes provide further motivation to leave to coastal cities.
Blue collar workers will move to the coasts seeking employment in constructing dikes and dams to protect coastal cities from rising ocean levels and hurricanes. White collar workers follow the corporations that move to the coasts either because of city/state bankruptcy or increased corporate taxes, or find employment in the new industries developed to coordinate and build physical contingencies for coastal climate change. Eventually, the entire U.S. population is clustered on the coasts, with a vast Heartland wasteland.