Thu, Apr 18, 2013 - Page 9 News List

A warming world threatens our food supplies

Global warming is exacerbating political instability as tensions brought on by food insecurity rise, and new research suggests the issue can only get worse

By John Vidal  /  The Guardian, LONDON

A new study of 11 West African countries expects most to be able to grow more food as temperatures rise and rainfall increases. However, demand from growing populations may double food prices. Climate change may mean Nigeria, Ghana and Togo can grow and export more sorghum, raised for grain.

Temperatures are expected to rise several degrees in regions close to the Sahel. In Burkina Faso, the sorghum crop is expected to decline by 25 percent or more, but maize yields may improve.

Other studies by the International Food Policy Research Institute suggest crop yields across sub-Saharan Africa may decline 5 percent to 22 percent by 2050, pushing large numbers of people deeper into destitution.

A new UN study suggests climatic conditions in southern Africa will worsen. Climate models mostly predict an increase in annual maximum temperatures in the region of 1°C to 2°C by 2050. This will favor some crops but shift others to higher ground or further north.

Both of Africa’s staple crops, maize and sorghum, are expected to be badly hit by increasing severity of weather.

Oxfam warns that small-scale farmers in the Horn of Africa will bear the brunt of the negative impacts of climate change. Unpredictable weather here has already left millions semi-destitute and dependent on food aid.


The US is expected to grow by 120 million people by 2050. Government scientists expect more incidents of extreme heat, severe drought, and heavy rains to affect food production. The warming is expected to continue without undue problems for 30 years, but beyond 2050 the effects could be dramatic with staple crops hit.

According to the latest government report: “The rising incidence of weather extremes will have increasingly negative impacts on crop and livestock productivity, because critical thresholds are already being exceeded. Many agricultural regions of the US will experience declines in crop and livestock production. Climate disruptions have increased in the recent past and are projected to increase further over the next 25 years.”

California’s Central Valley will be hard-hit with sunflower crops, wheat, tomato, rice, cotton and maize all expected to lose 10 percent to 30 percent of their yields, especially beyond 2050. Fruit and nut crops, like cherries, grapes and groundnuts, which depend on having a certain number of “winter chilling” days may have to relocate. Animals exposed to many hot nights are increasingly stressed. Many vegetables crops will be hit when temperatures rise only a few degrees above normal.

Because nearly 20 percent of all US food is now imported, climate extremes in countries that supply the US will affect the price of US food. In 2011, 14.9 percent of US households did not have secure food supplies and 5.7 percent experienced very low food security.

Because few crops can withstand average temperature rises of more than 2°C, Latin America expects to be seriously affected by a warming climate and more extreme weather events. Even moderate 1°C to 2°C rises in temperatures would cause significant damage to Brazil, which has emerged as one of the world’s biggest suppliers of food crops. Brazilian production of rice, coffee, beans, manioc, maize and soya are all expected to decline, with coffee, a mainstay of many other Latin American economies, especially vulnerable because it is so sensitive to heat and diseases.

This story has been viewed 2248 times.

Comments will be moderated. Remarks containing abusive and obscene language, personal attacks of any kind or promotion will be removed and the user banned.

TOP top