A warming climate could open millions of square kilometres of Canada’s North to growing wheat and potatoes over the next half-century, according to a new study.
The environmental consequences of farming these “frontier” croplands, however, could be disastrous.
Researchers from the University of Guelph and Conservation International, a non-governmental organization, modelled the potential for growing staple crops in previously uncultivated territory amid a warming climate. In a new paper, they estimated the landmass available for agriculture globally could increase nearly one-third by 2080 under more dire warming scenarios – by as much as 15 million square kilometres.
“About 30 per cent to 40 per cent of that area falls in the Canadian North,” said Krishna Bahadur KC, adjunct professor and research scientist at the University of Guelph’s geography, environment and geomatics department. The region “could be a bread basket for the future,” he added.
Large swaths of Russia were also expected to become arable. In the Rocky Mountains and ranges in Central Asia, agriculture is expected to move further up mountain slopes, while fringes of deserts in Australia and Africa are expected to see increased precipitation.
Additional production from frontiers may help solve looming food shortages. The Food and Agriculture Organization of the United Nations predicted that Earth’s population will grow by 2.3 billion people between 2009 and 2050; food production would have to be raised 70 per cent to feed all those additional mouths.
But depending on how they’re exploited, frontiers may create as many problems as it would solve. Carbon locked in soils, equivalent to more than a century’s worth of emissions by the United States, might be released after just a few years of tillage.
Huge releases of greenhouse gases are already expected from Canada’s permafrost regions this century, which by themselves have already contributed to fears of “feedback loops” leading to runaway climate change. Farming the North could worsen that situation.
“Under the boreal forest, the huge amount of carbon is stored in that soil,” said Prof. KC. “As soon as we start cutting trees and farming, slowly that carbon will be released into the atmosphere.”
Elsewhere, significant biodiversity hot spots might be converted into farmland, causing particular harm to birds. And watersheds serving billions of people could be degraded.
Climate change’s impact on the availability of arable land has been studied for at least the past quarter century. This study’s results accord with previous work that found climate change might increase available cropland in countries at higher latitudes in the northern hemisphere. While University of Guelph study authors acknowledged this previous work, they said much of it overlooked the negative effects of cultivating these emerging farming frontiers.
"The trade-offs between environmental concerns and food production may be very significant,” said Evan Fraser, a co-author and director of the Guelph, Ont., university’s Arrell Food Institute.
The Guelph study considered future land suitability for 12 major crops under projections from 17 global climate models. Just four of those crops can tolerate the Canadian winter: Wheat and potatoes are expected to be most successful given expected future conditions, while small patches might become appropriate for growing corn and soy.
The range for potatoes, for example, could expand into the north of the Prairie provinces, northern Quebec, Labrador and even the Northwest Territories.
Even under the most extreme climate models, Canada won’t be growing large quantities of sorghum and cassava any time soon.
Remarkably, the study found that only relatively small areas of the world’s existing cropland – about 0.2 per cent – would be rendered unsuitable for agriculture by climate change.
Previous studies emphasized widespread decreases in agricultural suitability, particularly in tropical and subtropical regions. A 2014 federal study predicted that while longer, warmer growing seasons would allow farming farther north in Canada, such conditions would also foster more (and more severe) outbreaks of pests and diseases, weed growth “and other challenges that could negatively affect production.”
Guelph’s researchers emphasized that their high-level analysis shows the maximum amount of land that may become available for agriculture; they didn’t assess the economic feasibility of cultivating all that land, for example. Further studies would need to be conducted to assess soil characteristics, transportation infrastructure, receptivity of local communities and other local factors.
The federal government, for its part, does not estimate how much farmland may become available amid a warming climate. James Watson, a spokesperson for Agriculture and Agri-Food Canada, said there simply isn’t enough data about soil characteristics outside today’s agricultural heartlands to make an effective forecast –although the government is working to address this data gap.
Prof. KC said there are already isolated examples of northward migration of farming. “In the Northwest Territories, farmers are already practising growing soya on land that was never under agricultural activities until a few years ago,” he said. “In southern Manitoba, some farmers are already growing corn.”
Future agricultural opportunities could pose a moral dilemma for Canada and Russia. “Frontier cultivation may have significant economic, food security and trade benefits for these countries,” the researchers wrote in their paper.
“However, the likely environmental cost, especially related to climate change, will be felt internationally, with disproportionate impact on poor nations.”
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