Climate and the fate of corn

It is a remarkable thing that the U.K. and Irish parliaments were able to hypnotize themselves and pass climate emergency legislation when the southern half of the planet has not warmed at all in 120 years.  For example, this record of Cape Leeuwin (courtesy of Erl Happ), on the southwest corner of the Australian landmass, shows recent January mean maximum temperature back below the 120 average:

Figure 1: Cape Leeuwin January Mean Maximum Temperature 1897–2019.

The U.K. and Irish parliaments were able to work themselves up into a lather over climate even though parts of the northern hemisphere set new cold records this last winter.  A spike in food prices due to cold weather might get them to see the world as it really is.  What is happening in the Corn Belt this season may be enough to burn through the global warming groupthink.

It has been a very wet and cold start to the 2019 growing season in the Corn Belt, with the consequence that a lot of farmers have not been able to get into their fields to plant.  For example, this graph is from the USDA's Indiana crop progress report of May 20:

Figure 2: Crop Progress, Corn in Indiana May 20, 2019.

In a normal year, most of the crop would be planted by now.  It will now be delayed by a month if it does get planted.  Unplanted corn and soybean acreage is at a 40-year high:

Figure 3: Unplanted Corn and Soybean Acres after Week 20.

Projections of likely corn production from here rely upon near perfect conditions for the rest of the season.  But as a return to 19th-century level solar activity will mean a return to 19th-century growing conditions, then the other end of the growing season will be shortened as well.  Seed-producers have tuned their product to the longer and warmer growing conditions of the second half of the 20th century, with corn that requires 2,500 growing degree days (GDD) to reach maturity.  If the season looks as if it is going to be short, then farmers might switch to early maturity corn.  Another alternative is to switch to soybeans.  For 2019, there is "is not enough early maturity seed corn for everyone nor enough seed beans available to switch." 

Figure 4: Whitestown, Indiana Cumulative GDD for 1901–1910 and 2001–2010.

Figure 4 shows the difference between growing conditions last decade in red and the beginning of the 20th century in blue.  Each of the blue and red lines is an individual year.  Growing conditions last decade were warmer, longer, and safer than a century before.  The dashed black line shows the GDD for a corn crop planted on 27 May with the GDD trajectory of early 20th century heat profile.  The chance of a crop being killed off by an early frost before maturity is not insignificant now.

Corn as a source of food for humans in the U.S. has a buffer in the 30% of the crop that goes to the ethanol mandate.  The focus on climate may also go from being a way to thrash the economy with carbon taxes to its impact on food prices.  The biblical "years of lean" may be upon us.

David Archibald is the author of American Gripen: The Solution to the F-35 Nightmare.

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