Particularly stupid climate propaganda: Let's claim that a little extra warmth and carbon dioxide would be devastating to a crop that likes warmth and carbon dioxide

Global warming will make it hot for Indiana corn farmers | Reporter-Times / MD Times

Indiana corn farmers will lose an estimated $98 million a year as temperatures rise because of global warming, according to a study released Thursday.
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Environment America cited scientific literature, government reports and its own previous studies to support conclusions presented in the 10-page document. It focused on corn, calling America’s main cash crop “the canary in the coal mine,” which is susceptiple to lower yields caused by rising temperatures.

While not all effects of global warming will be bad for crops — a lower growing season and more carbon dioxide for plant growth were among potential benefits noted — the study concluded that benefits would be outweighed by negative impacts of global warming.

Those included more frequent and destructive storms, disease and insect proliferation, changing weather patterns and more widespread ozone pollution.

Indiana State Climate Office: Mean temperature is 74.3 F in July, the state's warmest month

Jul 74.3

Lesson 1b: Corn can thrive in very warm weather

The crop grows according to an "S"-shaped curve depending on temperature, with the ideal temperature for crop growth, if everything else is satisfactory such as nutrition and water availability, being somewhere around 93 F

Rising Carbon Dioxide is Great for Plants

Corn, sugarcane, sorghum, millet, and some tropical grasses use the C4 pathway, so named because the first products of photosynthesis have four carbon atoms per molecule. C4 plants also experience a boost in photosynthetic efficiency in response to higher carbon dioxide levels, but because there is little photo-respiration in C4 plants, the improvement is smaller than in C3 plants. Instead, the largest benefit C4 plants receive from higher CO2 levels comes from reduced water loss. Loss of water through leaf pores declines by about 33 percent in C4 plants with a doubling of the CO2 concentration from its current atmospheric level. Since corn and other C4 plants are frequently grown under drought conditions of high temperatures and limited soil moisture, this superior efficiency in water use may improve yields when rainfall is even lower than normal.