Climate Change May Turn Africa’s Dry Sahel Green

The Sahel is one of driest areas in Africa, but that may change if Earth's surface temperatures rise more than two degrees Celsius.
萨赫勒地区是非洲最干旱的地区之一，但是如果地球表面温度再升高两摄氏度，那么这一切可能会发生改变。
Scientists say the Sahel could turn greener, with more plant life, because the higher temperatures would lead to more rainfall.
科学家们表示，萨赫勒地区可能会拥有更多植物生命，变得更绿。因为更高的温度可能会导致更多的降雨。

More than 100 million people live in the Sahel. It stretches coast to coast -- from Mauritania and Mali in western Africa to Sudan and Eritrea in the east. The Sahel extends to the southern edge of the Sahara desert.
有超过一亿人居住在萨赫勒地区。它横跨东西海岸，从西部的毛里塔尼亚和马里，一直到东部的苏丹和厄立特里亚。萨赫勒地区还延伸到了撒哈沙漠南部边缘。

In recent years, the area has experienced worsening extreme weather. That includes more droughts -- periods of little or no rainfall.
近年来，该地区经历了不断恶化的极端天气，其中包括更多干旱，也就是少雨甚至无雨的时期。

Some scientists are very concerned about pollution from greenhouse gases - gases that trap heat in Earth's atmosphere. They warn that if such gases continue to increase with no limits, rising temperatures could change weather systems in the Sahel and other areas. Scientists say this is possible if surface temperatures rise more than two degrees Celsius above average temperatures before the industrial revolution.
一些科学家一直非常关注温室气体污染。温室气体是指地球大气层中捕获热量的气体。他们警告说，如果这些气体继续不受限制的增长，气温不断上升可能会改变萨赫勒等地区的天气系统。科学家们表示，如果地球表面温度比工业革命之前的平均气温高出两摄氏度，这就是可能的。

Competing rainfall models
矛盾的降雨模型

Some weather models predict a small increase in rainfall for the Sahel. But there is a risk that the entire weather pattern will change by the end of the century. That is the opinion of researchers at the Potsdam Institute for Climate Impact Research.
一些天气模型预测萨赫勒地区降雨会小幅增加。但是到本世纪末，整个天气模式都存在改变的风险。这是德国波茨坦气候影响研究所的研究人员的结论。

The size of the possible change is "mind-boggling," says the institute's Anders Levermann. "This is one of the very few elements in the Earth system that we might witness tipping soon." Levermann also works for Columbia University in New York City.
该研究所的安德斯·莱弗曼（Anders Levermann）说，可能发生的这种改变的规模是“令人难以置信的。”“这是地球系统中很少有的恶劣天气之一，我们可能很快就会亲眼见证到转折。”

If the Sahel receives more rainfall, it will mean more water for agriculture, industry and personal use. But in the first few years leading up to more rain, the area is likely to experience very erratic weather. That may mean extremely dry periods followed by destructive floods, the researchers said.
如果萨赫勒地区获得更多降雨，就意味着会有更多农业、工业和个人用水。但是在即将迎来更多降雨的最初几年里，该地区的天气可能会非常不稳定。研究人员表示，这可能意味着极端干旱时期，紧随而来的就是毁灭性的大洪水。

Hard for people to plan
人们难做规划

They added that because it is hard to know what will happen when, it makes it hard for people to plan for these changes.
他们补充说，因为很难知道会发生什么，什么时候发生，这使得人们难以对此做出规划。

Levermann said any extreme change would create a huge challenge to the Sahel. More than 100 million people who may be affected already face many "instabilities, including war," he said.
莱弗曼说，任何极端变化都会给萨赫勒地区带来巨大挑战。他说，可能受此影响的一亿多居民面临多重的不稳定，包括战争在内。

The area faces many conflicts, including some driven by groups such as Boko Haram and al Qaeda in the Islamic Maghreb.
该地区面临多种冲突，包括博科圣地组织和伊斯兰马格里布基地组织这类组织造成的一些冲突。

The researchers studied rainfall in the Sahel during the months of July, August and September. That is the time of year when the area gets most of its rain.
这些研究人员调查了萨赫勒地区7-9月期间的降雨情况。这是该地区全年降雨最多的时期。

There are a number of possible outcomes, which depend on the climate that eventually develops... and whether people in the Sahel are prepared for changes, said scientist Jacob Schewe.
科学家雅各·谢尔韦（Jacob Schewe）表示，有可能会出现多种结果，这主要取决于气候的最终发展以及萨赫勒地区居民是否对此变化做好应对准备。

"Climate change from burning fossil fuels "really has the power to shake things up," he told the Thomson Reuters Foundation.
他对汤姆森路透基金会表示：“燃烧化石燃料导致的气候变化确实有能力让一切重新洗牌。”

A report on the study was published this month in Earth System Dynamics, a journal of the European Geosciences Union.
该研究报告本月发表在欧洲地球科学联合会的《地球系统动力学》杂志上。