E Climate has been a major driver of armed conflict in Africa, research shows—and future warming is likely to increase the number of deaths from war. US researchers found that across the continent, conflict was about 50% more likely in unusually warm years. Writing in Proceedings of the National Academy of Sciences (PNAS), they suggest conflict arises when the food supply is not enough in warm conditions. Climatic factors have been mentioned as a reason for several recent conflicts. One is the fighting in Darfur in Sudan that has killed 200,000 people and forced two million more from their homes. Previous research has shown an association between lack of rain and conflict, but this is thought to be the first clear evidence of a temperature link. The researchers used databases of temperatures across sub-Saharan Africa for the period between 1981 and 2002, and looked for connections between above average warmth and civil conflict in the same country that left at least 1,000 people dead. 'Studies show that crop output in the region is really sensitive to small shifts in temperature, even of half a degree or so,' research leader Marshall Burke, from the University of California at Berkeley, told BBC News. 'Our findings provide strong motivation to increase investments in African adaptation to climate change by such steps as developing crop varieties less sensitive to extreme heat and promoting insurance plans to help protect farmers from negative effects of the hotter climate,' said Dr Burke. 'If the argument is that the trend towards rising temperatures will increase conflict, then we need to do something around climate change, but more fundamentally we need to resolve the conflicts in the first place.' If the sub-Saharan climate continues to warm and little is done to help its countries better adapt to high temperatures, the human costs are likely to be unimaginable. If temperatures rise across the continent as computer models project, future conflicts are likely to become more common, researchers suggest. Their study shows an increase of about 50% over the next 20 years. When projections of social trends such as population increase and economic development were included in their model of a future Africa, temperature rise still emerged as a likely major cause of increasing armed conflict. At next month's UN climate summit (峰会) in Copenhagen, governments are due to debate how much money to put into helping African countries prepare for and adapt to negative effects of climate change. 57．According to the passage, which of the following is one of the reasons for the fighting in Darfur in Sudan? A．Shortage of drinking water.                         B．Racial discrimination. C．Rising temperature.                                     D．Demand for planting land. 58．What can we know from the research done by the US researchers? A．There is no close relation between rainfall and conflict. B．Temperature greatly affects crop production in sub-Saharan Africa. C．Temperature will rise by about 50% in Africa over the next two decades. D．With world cooperation, conflicts in Africa will be reduced by half 20 years later. 59．What can be inferred from the passage? A．Something must be done to help sub-Saharan countries with better adaptation to climate change to avoid disaster. B．Conflicts in sub-Saharan countries are sure to be on the rise in future. C．Temperature in sub-Saharan countries will rise at a faster speed. D．High temperatures will make sub-Saharan countries unfit to live in. 60．What's the best title for this passage? A．World cooperation against African conflict B．Africa's sufferings from climate change C．Food shortages lead to African conflict D．Climate drives African conflict