Climate change threatens food supply
Albertans must save soil and water to adapt, says expert
Wednesday, Apr 02, 2014 06:00 am
Climate change will mean tougher times ahead for Alberta farmers, suggests a new international report, and one of its authors says that means farmers need to act now to adapt.
The Intergovernmental Panel on Climate Change (IPCC) released Part Two of its Fifth Assessment report Monday. The international group draws thousands of researchers together to determine the state of climate change and what nations should do about it.
Part One, released last fall, focused on the state of climate change science. The report found that it was “virtually certain” that the world’s climate had warmed since the 1950s and that it was “extremely likely” (i.e. more than 95 per cent) that human influence was the dominant cause of this warming.
Part Two looks at the impacts of climate change, now and in the near future, and what nations must do to adapt to them.
“Nobody on this planet is going to be untouched by the impacts of climate change,” said Rajendra Pachauri, chair of the IPCC, speaking at a press conference in Yokohama, Japan.
It has already led to species migrations, shrinking glaciers and reduced crop yields, he noted. “This has serious implications for food security,” he said, especially for poor nations.
Alberta is already seeing shrinking snowpack and earlier spring runoff because of climate change, said sociologist Debra Davidson, a professor at the University of Alberta and one of the lead authors of this report’s chapter on North America.
“We could end up in a situation in which we have serious water availability concerns in those late summer months when we need water the most for agriculture.”
Crops feel the heat
It’s now clear that the world is locked into at least two degrees of warming by 2050, Davidson said. “The impacts that will roll out over the next few decades are more or less inevitable.”
The report notes significant shrinkage in glaciers worldwide, which threatens water supplies downstream. Shifts in temperature and precipitation had already caused significant dips in productivity for corn and wheat – both major food crops.
Tropical regions can expect significant declines in yield for major crops, Davidson said. The picture for Alberta is less clear – higher temperatures might benefit us, but climate change also brings more extreme weather, making any gains we see precarious.
“We are in very much a global food marketplace,” she continued, so climate-change-induced crop failures elsewhere affect us too. We’ve already seen price spikes in corn and wheat in recent years due to foreign crop failures, and will likely see a spike in fruit and vegetable prices this fall due to the drought in California.
The world was already at moderate risk of having more extreme weather events with its current level of warming, the report found. This would become a high risk if it warmed by two degrees above pre-industrial levels. “Extensive biodiversity loss with associated loss of ecosystem goods and services” was projected to occur at three degrees. “Irreversible regime shifts” in coral reefs (mass die-offs) and the arctic (mass ice loss) may already be in progress.
What’s frustrating is that we could have headed off many of these impacts had we started reducing greenhouse gas emissions 25 years ago, Davidson said. “We have to pay the price of avoiding mitigation in the past.”
Where to next
This was not an alarmist report, she continued. “It’s very much a pragmatic ‘here’s where to go next’ kind of report.”
That’s emphasized in one of the report’s most striking features: a chart showing the levels of risk world regions face from climate change and how stepped-up adaptation efforts can reduce those risks.
North America was currently at high risk of having more wildfires, for example, but could lower that risk to moderately high if it stepped up fire protection strategies. Wetland conservation could likewise lower the risk of greater urban flooding.
Farmers should emphasize soil and water conservation to prepare for climate change, Davidson said. Drought tolerant crops could also help.
Pachauri emphasized the need to mitigate climate change by reducing emissions as well. “If the world doesn’t do anything about mitigating the emissions of greenhouse gases and the extent of climate change continues to increase, then the very social stability of human systems could be at stake.”
The next IPCC report, due out April 13, will focus on mitigation.
The fifth assessment can be found at www.ipcc-wg2.gov/AR5.