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Panel Warns of Risks to Food Supply From Climate Change Climate Change Seen Posing Risk to Food Supplies
(about 2 hours later)
An international scientific panel has found that climate change will pose sharp risks to the world’s food supply in coming decades, potentially reducing output and sending prices higher in a period when global food demand is expected to soar. Climate change will pose sharp risks to the world’s food supply in coming decades, potentially undermining crop production and driving up prices at a time when the demand for food is expected to soar, scientists have found.
That finding is by far the starkest warning that the United Nations-appointed group, the Intergovernmental Panel on Climate Change, has ever issued regarding the food supply. Its last report, in 2007, was more sanguine, essentially finding that climatic warming and the rising level of carbon dioxide in the air would boost agricultural production across large areas, though that report did cite some risks. In a departure from an earlier assessment, the scientists concluded that rising temperatures will have some beneficial effect on crops in some places, but that globally they will make it harder for crops to thrive — perhaps reducing production over all by as much as 2 percent each decade for the rest of this century, compared with what it would be without climate change.
The warning is contained in a draft report that leaked on Friday. The document is not final and not scheduled for release until after an editing session in Yokohama, Japan in March. And, the scientists say, they are already seeing the harmful effects in some regions.
The draft report warns that sweeping impacts from climate change are already being seen across the planet, and that these are likely to intensify as human emissions of greenhouse gases continue to rise. The warnings come in a leaked draft of a report under development by a United Nations panel, the Intergovernmental Panel on Climate Change. The document is not final and could change before it is released in March.
Echoing past findings, the draft report points out that land ice is melting worldwide, leading to a rise of the sea that is putting coastal communities at increased risk of flooding. It describes a natural world in turmoil as plants and animals attempt to migrate to escape rising temperatures, and warns that many could go extinct. Saving a significant fraction of the world’s biological diversity may require far more aggressive human management of natural systems, the report declares. The report also finds other sweeping impacts from climate change already occurring across the planet, and warns that these are likely to intensify as human emissions of greenhouse gases continue to rise. The scientists describe a natural world in turmoil as plants and animals try to migrate to escape rising temperatures, and warn that many could become extinct.
Efforts to adapt to climate change have already begun in many countries, the report found; President Obama on Friday signed an executive order to step up such efforts in the United States. But these efforts remain inadequate compared with the risks, the report says, and far more intensive — and expensive — adaptation plans are likely to be required in the future. The warning on the food supply is the sharpest in tone the panel has issued. Its previous report, in 2007, was more hopeful. While it did warn of risks and potential losses in output, particularly in the tropics, that report found that gains in production at higher latitudes would most likely offset the losses and ensure an adequate global supply.
The report found that it is not too late for cuts in emissions to have a strong impact on the future risks of climate change, though the costs would be incurred in the next few decades and the main benefits would likely be seen in the late 21st century and beyond. The new tone reflects a large body of research in recent years that has shown how sensitive crops appear to be to heat waves. The recent work also challenges previous assumptions about how much food production could increase in coming decades because of higher carbon dioxide levels in the atmosphere. The gas, though it is the main reason for global warming, also acts as a kind of fertilizer for plants.
The Intergovernmental Panel on Climate Change is the principal scientific body charged with reviewing and assessing climate science, then issuing reports about the risks to the world’s governments. Its main reports come out every five to six years. The group won the Nobel Peace Prize, along with Al Gore, in 2007 for its efforts to alert the world to the risks. The Intergovernmental Panel on Climate Change is the principal scientific body charged with reviewing and assessing climate science, then issuing reports about the risks to the world’s governments. Its main reports come out every five to six years. The group won the Nobel Peace Prize, along with Al Gore, in 2007 for its efforts.
Hundreds of billions of dollars are being spent every year to reduce emissions, in direct response to past findings from the group, though many analysts have said these efforts are so far inadequate to head off drastic climatic changes later in the century. Hundreds of billions of dollars are being spent every year to reduce emissions in response to past findings from the group, though many analysts have said these efforts are so far inadequate to head off drastic climatic changes later in the century.
On the food supply, the new report finds that benefits from global warming may be seen in some areas, such as northern lands that are now marginal for food production. But it added that over all, climate change could reduce agricultural output by as much as 2 percent per decade for the rest of this century, compared with what output would be without climate change. On the food supply, the new report finds that benefits from global warming may be seen in some areas, like northern lands that are now marginal for food production. But it adds that over all, global warming could reduce agricultural production by as much as 2 percent each decade for the rest of this century.
During that period, demand is expected to rise as much as 14 percent each decade, the report found, as billions of people in developing countries acquire the money to eat richer diets. Rising food prices would likely hit the world’s poor hardest, as has already occurred from sharp price increases of recent years — spikes caused to a large extent by certain types of weather extremes, like severe heat waves, that have been linked to climate change. During that period, demand is expected to rise as much as 14 percent each decade, the report found, as the world population is projected to grow to 9.6 billion in 2050, from 7.2 billion today, according to the United Nations, and many of those people in developing countries acquire the money to eat richer diets.
Any shortfall would lead to rising food prices that would hit the world’s poor hardest, as has already occurred from price increases of recent years. Research has found that climate change, particularly severe heat waves, was a factor in those price spikes.
The agricultural risks “are greatest for tropical countries, given projected impacts that exceed adaptive capacity and higher poverty rates compared with temperate regions,” the draft report finds.The agricultural risks “are greatest for tropical countries, given projected impacts that exceed adaptive capacity and higher poverty rates compared with temperate regions,” the draft report finds.
If the report proves to be correct, global food demand might have to be met – if it can be met – by putting new land into production. That could entail chopping down large areas of forest, an action that would only accelerate climate change by sending substantial amounts of carbon dioxide into the air from the destruction of trees. If the report proves to be correct about the effect on crops from climate change, global food demand might have to be met — if it can be met — by putting new land into production. That could entail chopping down large areas of forest, an action that would only accelerate climate change by sending substantial amounts of carbon dioxide into the air from the destruction of trees.
The leak of the new draft occurred on a blog hostile to the scientific panel. The report finds that efforts to adapt to climate change have already begun in many countries. President Obama on Friday signed an executive order to step up such efforts in the United States. But these efforts remain inadequate compared with the risks, the report says, and far more intensive — and expensive — adaptation plans are likely to be required in the future.
“It’s a work in progress,” said Jonathan Lynn, a spokesman for the intergovernmental panel. “We don’t have anything to say about the contents. It’s likely to change.” The document also finds that it is not too late for cuts in emissions to have a strong impact on the future risks of climate change, though the costs would be incurred in the next few decades and the main benefits would likely be seen in the late 21st century and beyond.
But in a brief interview, Mr. Lynn did not dispute the authenticity of the document. In the Internet era, the group’s efforts to keep its drafts secret are proving to be a failure, and some of the scientists involved have called for a drafting process open to the public. The leak of the new draft occurred on a blog hostile to the intergovernmental panel. In a brief interview, a spokesman for the panel, Jonathan Lynn, did not dispute the authenticity of the document.
A report about the physical science of climate change leaked in August, then underwent only modest changes before its final release in Stockholm in late September. The new report covers the impacts of climate change, efforts to adapt to it, and the vulnerability of human and natural systems. “It’s a work in progress,” Mr. Lynn said. “It’s likely to change.”
Several scientists involved in drafting the document declined on Friday to speak publicly about it. In the Internet era, the group’s efforts to keep its drafts secret are proving to be a failure, and some of the scientists involved have called for a drafting process open to the public.
A report about the physical science of climate change leaked in August, then underwent only modest changes before its final release in Stockholm in late September. The new report covers the impact of climate change, efforts to adapt to it, and the vulnerability of human and natural systems.
A third report, analyzing potential ways to limit the rise of greenhouse gases, is due for release in Berlin in April.A third report, analyzing potential ways to limit the rise of greenhouse gases, is due for release in Berlin in April.