For example, one predic-tion is for

For example, one predic-tion is for a general reduction in crop yields in many tropical and sub-tropical regions for most projected increases in temperature, and a general reduction, with some variation, in potential crop yields in most mid-latitude regions for increases in annual temperatures of more than a few degrees Centigrade (Fischer et al., 1995). Perhaps the most serious current predictions relate to future failures of food supplies through diminished supplies of water. are projected for the Sahelian region of Africa, south Asia and large parts of Latin America as a consequence of shifting rain-fall belts.ความ
Approximately one-third of the world’s population (1.7 billion) already live in countries that periodically experience significant deficits in water supplies, and some reports predict that the population affected will rise to 5 billion by 2025., in central Asia, north and southern Africa, because of a combination of higher temperatures and pollutant runoff, decreases in rainfall will be associated with declining quality of water that is available. Against this portrayal of impending disaster, it is possible that some regions may benefit from predicted warming, which may enable new crops to be grown, e.g. extending the cultivated area northwards in parts of Canada.