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A dragonfly lands on a stalk of wheat ready for harvest during sunset on the Canadian prairies near Vulcan, Alta. (TODD KOROL/REUTERS)
A dragonfly lands on a stalk of wheat ready for harvest during sunset on the Canadian prairies near Vulcan, Alta. (TODD KOROL/REUTERS)

The myth about climate change Add to ...

Climate change is not all bad news. The higher temperatures that bring floods, droughts and wildfires also, broadly speaking, expand growing seasons and improve crop yields. We humans might drown in a flash flood or burn to a crisp in a midsummer heat wave, but we’d die with our stomachs full.

That, at least, was the theory.

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Indeed, the 2007 report of the United Nations’ Intergovernmental Panel on Climate Change (which won the Nobel Peace Prize that year) was fairly sanguine about the impact of climate change on harvests. The latest IPCC report, released in March, took a distinctly darker view. The summary of its final draft noted that the “Negative impacts of climate trends [on food production] have been more common than positive ones.”

It added that, without adaptation measures, temperature increases of more than one degree Celsius above pre-Industrial temperatures are “projected to have negative effects on yields for the major crops (wheat, rice and maize) in both tropical and temperate regions,” and that “with or without adaptation, negative impacts on average yields become likely from the 2030s.”

Canada, beware. The Prairie farmers and politicians who have convinced themselves that global warming presented more opportunities than problems – that Kansas’s loss would be Saskatchewan’s gain–might be guilty of wishful thinking.

Canada should no longer make agricultural investments based on century-old weather data. Instead, government and industry will need a strategy for Canada’s agriculture and food industries as rapid climate change goes from the theoretical to a truly scary reality. At the very least, Canada will need to take measures to minimize yield drop-offs. Using infrastructure, irrigation, genetic technology and the planting of warm-climate crops, it might even find ways to increase production as other parts of the world go hungry. Too bad there is little sign that such planning is taking place.

Rising atmospheric carbon dioxide levels and temperatures were not generally thought to be disastrous for global agriculture, even though some regions would get hit hard. Since CO2 is an input of photosynthesis, the theory was that higher CO2 concentrations would lead to higher yields for some crops, notably rice, wheat and soybeans, though less so for other big crops, such as maize and sugar cane. Recent research, however, suggests that the estimated gains from the “carbon fertilization” effect, while still real, were greatly exaggerated.

That’s one problem. The bigger problem is decreasing moisture as temperatures rise. The Stern Review of the Economics of Climate Change, presented to the British government in 2006, cited water stress as a prime reason for falling yields in some regions. In the Mediterranean basin and parts of southern Africa, a two-degree rise would trigger a potential 30 per cent decline in water runoff, the report said. That would send crop yields plunging.

Would Canada be a victim or beneficiary of global warming? Rising temperatures will no doubt lengthen the Prairie growing season and allow crop production in northern regions blessed with more soil than rock. But Agriculture Canada isn’t entirely bullish on climate change. It notes that the “prairie climate of the future will feature increased temperatures, a lack of moisture and increased rates of evaporation.” The result, it says, could be severe droughts and reduced yields. Remember that Russia banned wheat exports after the 2010 heat wave unleashed fires that devastated a third of the country’s cultivable land.

It is well known that the federal government, under Stephen Harper, is no friend to the environment. Canada was the only signatory to pull out of the Kyoto Protocol. It has been unravelling environmental and climate change research budgets. The Canadian Foundation for Climate and Atmospheric Sciences (now the Canadian Climate Forum) used to distribute $15-million a year in government funding. That funding ended in 2012. That same year, the Polar Environment Atmospheric Research Laboratory lost its funding, though it has since been partially restored.

According to the Canada 2020 think tank, $156-million a year is spent by the federal and provincial governments on agriculture research. That’s insignificant for an industry responsible for almost $50-billion a year in exports. If there’s a federal program devoted to adapting agriculture to climate change, no one has heard of it.

Compare that approach to the lavish attention the government pays to protecting the oil sands. The lobbying effort to save the Keystone XL pipeline, which would transport Alberta crude to the United States, has been formidable and expensive. Environmental assessments for energy projects have been made less burdensome. The industry that is a major source of CO2 is coddled. The industry that could feed the world, if it finds a way to adapt to climate change, is not.

Follow on Twitter: @ereguly

 

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