One of my habits in recent years has been studying climate history in my free time. What can I say; it keeps me out of bars.
Recently, I was startled to learn that the temperatures experienced by American wheat farms back in the 1830s were almost 7 degrees warmer than they now are.
At first I thought I had misread that statistic. After all, we know that temperatures in our country have been on the uptick since 1850 when North America emerged from a cooler era. And, surely, if climate scientists are right, temperatures in just the past couple of decades are clearly up from what they used to be.
So how could modern American wheat farmers be facing much colder climes than they were in the 1830s?
The answer is that wheat is now raised well to the west and north of where it was in the 1830s. Back then, the geographic center of wheat production was in eastern Ohio. Now, counties in central Montana, a corner of Wyoming, a strip of Colorado, and my own eastern Washington account for much of the American wheat that’s planted in the fall. Spring wheat comes largely from North Dakota.
Obviously, these are not balmy parts of the country.
Actually, there are a number of things about warmer temperatures that may help wheat farmers if predictions about 2050 hold true. In general, warmer conditions accelerate growth, usually a good thing for farmers. A potential negative is the drying of soil. Experiments on wheat under different temperature regimes show a complex impact on yield, with much depending on when wheat is planted. Happily, that’s one thing farmers can control.
According to the agricultural scientists I’ve spoken to, it’s really not average temperatures that cause farmers headaches. A truly cold or hot growing season is a greater problem than changes in average temperature over time. Alas, it’s departures from the average that are now in the forecast.
Wheat scientist Tim Murray, of Washington State University, helps ground my understanding of the challenges farmers face as climate evolves.
“Climate change is one of the reasons breeding programs are never-ending,” Murray told me recently. “Wheat has the genes to adapt to many conditions. The trick is finding those genes and incorporating them into new varieties at a pace that keeps yields high.”
It’s clear to me, our daily bread depends on exactly that.
Copyright 2012 Northwest Public Radio