The Crops Won’t Survive The Summer Heat

Corn and Soybean Belt – July Maximum Temperature (Updated with Trend)

1936 was hottest. 2009 was coldest. 1936 was 15.5F hotter than 2009.

 

corn-beslt-july

3 thoughts on “The Crops Won’t Survive The Summer Heat

  1. “Maximum July temperature” isn’t a good measure of how will plants survive.

    1) Overall sustained temperature is a better guide to how much heat stress plants experience. That involves both average temperature and how much things cool off at night. Both average temperature and nighttime temps hit record highs this year.

    2) In addition to heat, moisture content of the air and soil are vital, along with rainfall and soil nutrients. These are, of course, affected by average (not July maximum) global and regional temperature changes.

    3) Atmospheric CO2 matters also; a slight increase in atmospheric CO2 helps plants, but too much of it is harmful (the same way that more food gives humans more energy, but past a certain point, it causes a number of health problems.

    The crops we rely on evolved (and were bred) within a very narrow range of climate conditions, and don’t survive well if any of these are substantially altered. That’s why, for instance, wheat doesn’t grow well in the topics or near mountain tops.

    While we may be able to breed crops that can survive the coming altered conditions, these crops also rely on a variety of other environmental factors, such as the wild flora and fauna around them; particular pests they can withstand, birds and insects that prey on pests, bees and other insects for pollination, and so on. As the climate changes (in ways additional to July maximum temperatures), these will change as well.

    It is virtually certain that the length of the growing season will also change, as will the geographical areas in which our current crops can grow.

    All of which means the meme above — “crops can withstand minor changes in July maximum temperatures” — isn’t meaningful or helpful in understanding the challenges we will face.

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