Thomas Homer-Dixon is director of the Waterloo Institute for Complexity and Innovation and CIGI Chair of Global Systems at the Balsillie School of International Affairs in Waterloo, Ont
In the mid-1980s, when I was a doctoral student at the Massachusetts Institute of Technology and beginning to study climate change, I attended a lecture by a specialist in plant physiology at nearby Harvard University. He spoke about global warming’s impact on crop productivity. He was quite optimistic. More carbon dioxide in the air, he explained, causes certain kinds of plants to grow faster. So, on balance, food output should rise in a warmer and CO2-rich world.
I chased him down after the lecture and pressed him on things that could make plant response more complex. If plants absorb more CO2, I asked, won’t that change the nitrogen-carbon balance in their tissues and make them less nutritious? And what about other factors that might change in a warmer world, such as soil moisture and the distribution of weeds and pests – shouldn’t we take them into account, too?
He agreed that the issue was more complex than he’d suggested. “But we don’t have good data on these other factors yet,” he said, “so I didn’t talk about them.”
Almost three decades later, we have vastly more data, and the picture is far less rosy. We’ve learned that in the real world, unlike in experimental plots that control everything except ambient CO2 concentration, factors like drier soil and worse pest infestations can swamp carbon dioxide’s positive effect. And one thing that didn’t figure much in experts’ analysis in those days, and which I didn’t ask the Harvard speaker about, turns out to be a really big deal: heat shock.
In the past few years, agricultural scientists have shown that crops critical to humankind’s caloric supply – including corn and soybeans – are extremely sensitive to even short periods of high temperature. Output of these crops increases as the temperature rises to about 30 Celsius, but then it falls sharply as the temperature keeps rising. For instance, just one day of 40-degree weather will produce a 7-per-cent drop in the annual yield of corn compared with its yield if the temperature stays at 29 through the growing season.
In the past, 40 degrees might have seemed unusual, but nowadays it isn’t. In recent weeks, temperatures have topped this level repeatedly in key corn-growing states such as Nebraska, Iowa, Illinois and Indiana. The U.S. grain-growing regions are being hit, in fact, by a particularly brutal combination of drought and high heat.
Climate-change skeptics will dismiss this summer’s North American weather as just that – weather. They’ll argue it says nothing about longer-term climate trends. It’s true that the U.S. droughts of the 1950s and 1930s were worse than the current one, at least so far. But even without getting into the causes of this unusually hot and dry summer, data clearly show that the frequency of extreme weather is soaring around the world. For example, in the 1950s, summertime heat events that scientists classify as abnormally severe – technically, those that are at least three standard deviations from the average temperature and that experts call “three-sigma events” – affected less than 1 per cent of Earth’s land area. Now, in any given summer, three-sigma events affect about 10 per cent of our land area.
What’s happening in the United States is a window on the future. If humankind continues on its current emissions path, and if countries don’t invest far more in research to develop crops resistant to drought and high heat, climate change will depress global food production in the coming decades, just when our population is climbing toward 10 billion.
It sounds harsh, but in light of these realities, this year’s U.S. drought is good news. The sooner we get serious about climate change, the better our chances of keeping temperatures from rising too high. The drought and heat wave have already led to record corn prices. The world’s integrated grain markets will transmit these higher prices around the world, in time affecting just about everyone.
People may not care much about climate change, but most do care about the price of food because it affects their everyday lives. Fears about imperiled food security may be our best hope for breaking through widespread climate-change denial and generating the political pressure to do something, finally, about the problem.
Thank you, Dr. Homer Dixon!
We all know, however, that Mr. Harper is neither listening, nor reading such pieces. Neither apparently is Peter Kent, the current occupant of the office of Minister of the Environment, an apparent revolving door to the office continues to swing and no one knows the length of Kent's tenure..or if he even has any.
We also know, sadly, that the corporate culture of profit-seeking at the expense of both worker safety and environmental protection is, like the NRA in the U.S., the supreme agenda-setter for cultural norms.
Just as 'the U.S. has surrendered to the NRA" (see Lawrence Martin's column in the Globe and Mail, July 25, 2012) so too has the Canadian political culture surrendered to the corporate/Harper cabal, in its refusal to move to impose limits on carbon emission, or any real effective standards on the environmental impact of the tar sands heavy crude extraction.
Finding some positive news in the current drought, and the impact it is going to have on food prices, and thereby on the conversation at every kitchen table in North America, in the hope that such conversations will finally awaken the public to the political negligence being committed consciously and deliberately in both Washington and in Ottawa, is like finding a nugget of gold in the Ottawa River, which, if I read history correctly hasn't seen gold in the history of this country, a little exaggerated.
Nevertheless, one can and does always have hope, even if it hangs like a popsicle on a thread in 100 degrees F, in Southern Ontario in July of 2012.
One might have hoped, instead, that we would not have to commodify the environmental impact of climate change (on the price of food, for example) to arouse the public's concern, even compassion for all, to demand that significant actions be taken by governments on both sides of the 49th parallel. However, since cigarette smoking continues to rise among young people, especially young women, in the face of incontrovertible and legitimate data of the impact of smoking on both health and length of life, why would anyone wonder that an even more abstract notion like climate change and global warming would have any impact on an "instant gratification seeking" narcissistic electorate, whose concerns and fears have so many magnets drawing them in so many different directions.