为了减缓全球变暖，农业必须改变

为了减缓全球变暖，农业必须改变

Humans must drastically alter food production in order to prevent the most catastrophic effects of global warming, according to a new report from the United Nations panel on climate change.

联合国气候变化专门委员会(United Nations panel on climate change)的一份最新报告显示，为了防止全球变暖带来的最严重灾难性影响，人类必须大幅改变粮食生产。

The panel of scientists looked at the climate change effects of agriculture, deforestation and other land use, such as managing grasslands and wetlands. Together, those activities generate about a third of human greenhouse gas emissions, including more than 40% of methane.

这个科学家小组研究了农业、森林砍伐和其他土地利用(如管理草原和湿地)对气候变化的影响。这些活动总共产生了约三分之一的人类温室气体排放，包括超过40%的甲烷。

That's important because methane is particularly good at trapping heat in the atmosphere. And the problem is getting more severe.

这一点很重要，因为甲烷特别善于在大气中吸收热量。问题变得越来越严重。

"Emissions from agricultural production are projected to increase," the authors warn. "Delaying action" on reducing greenhouse gas emissions, they continue, "could result in some irreversible impacts on some ecosystems."

“农业生产的排放预计会增加，”作者警告说。他们继续说，在减少温室气体排放方面的“拖延行动”“可能对某些生态系统造成一些不可逆转的影响”。

This is the latest in a series of reports from the U.N.'s Intergovernmental Panel on Climate Change. The new report adds weight and detail to a warning put out by the same panel of scientists last fall, in which they sounded the alarm about the inadequacy of the pledges countries have made so far to reduce greenhouse gas emissions.

这是联合国政府间气候变化专门委员会(ipcc)一系列报告中的最新一份。这份新报告为去年秋天同一个科学家小组发出的警告增加了分量和细节。去年秋天，他们对各国迄今在减少温室气体排放方面做出的承诺不足发出了警告。

At that time, the panel broadly suggested that farmland would need to shrink and forests would need to grow to keep Earth from getting more than 1.5 degrees Celsius hotter than it was in the preindustrial era. Global temperatures have already risen about 1 degree Celsius in the past 150 years.

当时，该小组广泛建议，农田需要缩小，森林需要扩大，以防止地球温度比前工业化时代升高1.5摄氏度以上。在过去的150年里，全球气温已经上升了大约1摄氏度。

To meet that temperature target, global greenhouse gas emissions will need to fall by 40% to 50% in the next decade. Scientists say the only way to achieve that reduction is to significantly increase the amount of land that's covered in trees and other vegetation and significantly reduce the amount of methane and other greenhouse gases that come from raising livestock such as cows, sheep and goats.

为了达到这一温度目标，全球温室气体排放需要在未来十年下降40%到50%。科学家表示，实现这一目标的唯一途径是显著增加树木和其他植被覆盖的土地面积，并显著减少饲养奶牛、绵羊和山羊等牲畜所产生的甲烷和其他温室气体。

The new report offers some broad suggestions for how countries might achieve that. For example, for countries that have lost tree cover in the past century, reforestation can help suck greenhouse gases out of the air, while also preventing soil from drying up. Reducing food waste can also help reduce a country's greenhouse gas footprint.

这份新报告为各国如何实现这一目标提供了一些广泛的建议。例如，对于上个世纪失去树木覆盖的国家来说，重新造林可以帮助吸收空气中的温室气体，同时防止土壤干燥。减少食物浪费也有助于减少一个国家的温室气体足迹。

Controlling emissions from agriculture is also a food-security issue. Greenhouse gases from food production create a vicious cycle: As Earth gets hotter, farming gets more difficult in many places, which forces farmers to clear more land to grow food.

控制农业排放也是一个粮食安全问题。粮食生产产生的温室气体形成了一个恶性循环:随着地球变暖，许多地方的农业生产变得更加困难，这迫使农民开垦更多的土地来种植粮食。

"Climate change, including increases in frequency and intensity of extremes, has adversely impacted food security and terrestrial ecosystems, as well as contributed to desertification and land degradation in many regions," the report's authors write.

报告的作者写道:“气候变化，包括极端情况发生的频率和强度的增加，对粮食安全和陆地生态系统产生了负面影响，并导致许多地区的荒漠化和土地退化。”

If greenhouse gas emissions continue to increase, as they are doing today, it will exacerbate those challenges and eventually make it all but impossible to control global warming without creating serious food shortages.

如果温室气体排放量继续增加，就像他们今天所做的那样，这将加剧这些挑战，最终使控制全球变暖而不造成严重的粮食短缺几乎是不可能的。