一张图看清芝士汉堡和气候变化的关系

说起气候变化，人们往往会谈论碳排放的影响——具体点就是燃烧汽油、煤炭或者其他化石燃料的产生二氧化碳。可是常常忽略甲烷，其实甲烷也是所谓的温室气体之一，也是人类食物链的一大副产品。乳制品、肉牛和其它家畜饲养等活动会排放甲烷，动物粪便分解也会产生一些。

在人类活动排放的甲烷中，由化石燃料导致的占29%，反刍动物占27%，废物分解占23%，其他占21%。（ 来源：《自然-地球科学》期刊）

不管具体产生过程如何，许多环保人士已经提出，世界各国应该提高食品供应的效率，减少对肉食的依赖，从而遏制甲烷排放增长的势头。荣登今年《财富》杂志“改变世界”榜单（Change the World）的两家公司各自从不同方面设法解决甲烷问题。丹麦生物工程公司诺维信生产的酵素可以帮助动物消化饲料，从而提高食物供应的效率。英国饮食服务企业金巴斯集团则在努力降低每日上百万份餐食的红肉含量。（财富中文网）

译者：Pessy

审校：夏林

When people talk about climate change, they usually discuss the impact of carbon emissions—more specifically, the carbon dioxide that’s produced when we burn gasoline, coal, or other fossil fuels. But methane is also a so-called greenhouse gas—and it’s a big by-product of our food chain. Some of it comes out of the, um, back ends of dairy and beef cattle and other livestock; some of it is emitted when animal waste decomposes.

Whatever the source, many environmentalists argue that the world needs to make its food supply more efficient and less meat-dependent in order to curb its methane problem. Two companies on this year’s Fortune Change the World list are attacking the issue from different directions. Novozymes (#9 on the list) NVZMY -1.10% , a Danish bioengineering company, sells enzymes that make animal feed more digestible, and therefore more efficient. Compass Group (#33) CMPGY 0.10% , a British institutional food-service company, is reducing the amount of red meat in the millions of meals it serves every day.