If emissions of greenhouse gases continue to increase unchecked, they could push the Earth's surface temperature up by at least 4.3 degrees Fahrenheit (2.4 degrees Celsius) by 2020, and have devastating ramifications for global food production in a more crowded world, according to a new report.
By the end of the next decade the global population is projected to increase by about 900 million. Meanwhile, the report projects a 14 percent gap between production and demand for wheat, meaning demand will be 14 percent greater than production. For rice, this global gap is 11 percent and for corn, it's 9 percent. Only soybeans increase, with an estimated 5 percent surplus, according to The Food Gap – The Impacts of Climate Change on Food Production: A 202 Perspective, a report produced by the Universal Ecological Fund (Fundación Ecológica Universal, or FEU-US), a nonprofit. [ 7 Perfect Survival Foods ]
The report is based on key documents published by the Intergovernmental Panel on Climate Change (IPCC) and other United Nations agencies, officials of the group said.
Another study out this month, based on a computer model, found that even if humans stop producing excess carbon dioxide in 2100, the lingering effects of global warming could span the next millennia. So by the year 3000, global warming would be more than a hot topic — the West Antarctic ice sheet could collapse, and global sea levels would rise by about 13 feet (4 meters), according to that study.
Past the threshold
If concentrations of greenhouse gases, like carbon dioxide, continue to increase in the atmosphere, as the IPCC's Fourth Assessment report projects, global temperature could rise by 4.3 degrees F. For comparison, a 2-degree-F increase above pre-industrial times has been determined to be dangerous, according to the report.
"Over the entire world, extreme weather and climate events would be registered. Further increases in global mean surface temperature will exacerbate the intensity of these events," said Osvaldo Canziani, a scientific adviser on the report and FEU-US, a Nobel laureate, and co-chair of the second IPCC working group.
The report points out that climate change would most affect two of the three main elements of food production – water and climate. The geography of food production would change because of shifts in rainfall, increased demand for water for irrigation and increases in local temperatures.
Lean times to come
The report projects the effects of climate change on the world's four major food crops: wheat, rice, corn and soybeans. The projected deficits would affect human food supplies as well as livestock production, since about 35 percent of the world's cereals are used as animal feed, according to the Food and Agriculture Organization of the U.N.
As a result, food prices could increase up to 20 percent in the next decade, according to the IPCC.
Currently, the FAO reports that about one person in seven is undernourished. As a consequence of more costly food, that ratio would increase to one in five by 2020.
The world can still respond by reducing greenhouse gas emissions, adapting to changes through measures like relocating crops and changing the global diet, shifting to more roots and tubers, like sweet potatoes, and consuming protein from more sources other than meat, such legumes, the researchers say.
"The human cost of inaction could be devastatingly expensive — not only for future generations, but for this one," said Liliana Hisas, executive director of FEU-US and co-author of the report.
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