Food: Worse times ahead

Climate Change + Higher temperatures + Droughts + Floods + Soil erosion + Loss of topsoil + Pollution + Ground-level Ozone = Much Less Food in the Future

Scientists are warning that global warming would present great challenges on the way to produce more food in the future.

“There certainly are going to be lots of challenges in the future. Temperature is one of them, water is another,” said Lisa Ainsworth, a molecular biologist with the United States Department of Agriculture.

“In Northeastern China, low temperatures, a short growing season and lack of water limit production, so rising temperatures in the future may have beneficial impacts there,” said Ainsworth.

“However, in the southern parts of the country, higher temperatures will likely cause yield losses,” she told the reporters.

Higher temperatures coupled with ground-level ozone, which is produced as a result of sunlight interacting with greenhouse gases, added to extremes of floods and droughts is a recipe for disaster.

Ozone is a growing problem in the northern hemisphere and is already costing farmers billion of dollars in crop damage.

Effect of increasing ozone concentration (left to right: about 15, 80 and 150 ppb) on growth of (A) Pima cotton and nutsedge grown in direct competition with one nutsedge per cotton; (B) tomato and nutsedge
grown in direct competition with nutsedge (two-to-one); and (C) yellow nutsedge grown in the absence of competition. (Photo and caption: David A. Grantz & Anil Shrestha, UC Kearney Agricultural Center )

“In the major rice-growing regions, which are India and China, ground-level ozone concentrations even today are very high and certainly exceed the threshold for damage. Ozone is already decreasing yield potential in many areas,” Ainsworth said.

Significant amounts of rice yield are lost annually due to various abiotic stresses (e.g., salinity, droughts). Rice is the staple diet for about half of the world population, and about 90 percent of the world’s rice is produced in Asia.

UN experts believe that in low-latitude regions, slightest temperature rises of about 1ºC could affect crop yields.

The atmospheric CO2 levels have now reached about 388 parts per million from about 280 ppm prior to the Industrial Revolution.

“There is still a lot of uncertainty in the climate modeling when it comes to the regional level,” said Reiner Wassmann coordinator of the Rice and Climate Change Consortium at IRRI. “But it was clear temperatures would rise.”

A train travels along the flooded Darbhanga-Sitamadhi railway line in Bihar in this August 2, 2007 file photo. Massive monsoon floods in eastern India damaged vast areas of corn and affected the rice crop, government officials and farm experts said on Tuesday, adding that losses are being assessed. REUTERS/Krishna Murari Kishan (image may be subject to copyright!) See FEWW Fair Use notice.

“The other mega trend we see is that we will have more climate extremes. In some places there might be more drought, in others it may be submergence, from floods, in some places it might be both,” said Wassmann.

Lake Hartwell, February 2008, western South Carolina. Photo courtesy South Carolina Department of Natural Resources staff. (Source UNL)

“That is really a new challenge for development of cropping systems and I don’t want to limit it to only plant breeding. We have to be clear that this is no silver bullet and that if we speed-up plant breeding everything will be fine. Certainly not.

“We also have to improve crop management and water saving techniques have come into the picture to cope with drought,” he said. (Source)

High ozone levels can damage leaves on trees and crops (such as corn, wheat, and soybeans), reducing growth rates and crop yields. In 1995, ground-level ozone caused $2.7 billion in crop damage nationwide, according to the U.S. Environmental Protection Agency. Due to its reactive nature, ozone also can prematurely degrade and wear out rubber, paints and other materials. (Source)

Related Links:

• Food in the Future
• Farmers face climate challenge in quest for more food
• Trends in Atmospheric Carbon Dioxide – Mauna Loa
• Ozone reduces crop yields and alters competition with weeds such as yellow nutsedge

• Fueling Food Shortages
• Corn for Food, NOT for Fuel
• Food Riots Grip Egypt, Haiti, El Salvador
• Emerging Food Crisis
• World Poverty Index

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