煤炭产量下降使美国食品价格下降

煤炭产量下降使美国食品价格下降

The collapse of the American coal industry is having major benefits for the nation's health, but it's also having a less-heralded effect: it's boosting crop yields and making food prices cheaper.

美国煤炭工业的崩溃对国家的健康有很大的好处，但它也有一个不那么明显的影响:它提高了农作物产量，降低了食品价格。

Coal burning is a major contributor to air pollution, which causes an estimated 3-9 million deaths a year worldwide. Among the pollutants are nitrogen oxides, particularly from coal plants, which react in sunlight with other molecules to produce ozone. Although the shield of all life on Earth in the stratosphere, close-to-ground-level ozone is harmful both to animals and plants, accounting for an estimated 90 percent of air pollution's effects on crop yields.

煤炭燃烧是造成空气污染的主要原因之一，据估计，全球每年有300万至900万人死于空气污染。污染物中有氮氧化物，特别是来自燃煤电厂的氮氧化物，它在阳光下与其他分子发生反应，产生臭氧。尽管臭氧是地球上所有生命的保护层，但近地面的臭氧对动植物都是有害的，估计占空气污染对农作物产量影响的90%。

Stephen Luntz

The damaging effect of low-atmosphere ozone on human lungs has been incorporated into estimates of pollution's costs, but the impact on crops has been largely ignored. A paper in the American Journal of Agricultural Economics sets out to address this, examining the benefits of declining ozone on two of America's largest crops as coal use declined from 2003-2013.

低大气臭氧对人类肺部的破坏作用已被纳入污染成本的估算，但对农作物的影响基本上被忽视了。《美国农业经济杂志》上的一篇论文着手解决这个问题，研究了随着2003年至2013年煤炭使用量的下降，臭氧对美国两大农作物的影响。

Inevitably the picture varies by location – some farms are still exposed to as much ozone as they ever were, while others were always too far away to be affected much. However, by combining the entire farm belt, first author Dr Konstantinos Metaxoglou of MIT concludes corn yields rose 2.5 percent as a result of coal plant closures, while soybean production increased 1.6 percent.

不可避免的是，不同地区的情况有所不同——一些农场仍然暴露在与以往一样多的臭氧下，而另一些农场总是离得太远，不会受到太大影响。然而，通过结合整个农业区，第一作者、麻省理工学院的康斯坦丁诺斯·梅塔索格鲁博士得出结论，关闭燃煤电厂导致玉米产量增加2.5%，大豆产量增加1.6%。

Those sound like small effects, but the scale of these crops means the economy benefited by $1.6 billion every year. Plenty more coal plants have shut down since the end of Metaxoglou's study period, so must now be considerably larger.

这些影响听起来很小，但这些作物的规模意味着经济每年受益16亿美元。自从Metaxoglou的研究期结束以来，已经有更多的燃煤电厂关闭，所以现在肯定要大得多。

Corn farmers downwind of shuttered power stations gained 7 percent in production and would have been the prime beneficiaries. However, Metaxoglou calculates overall the falling prices caused by the increased supply meant farmers actually lost money. Consumers, however, now had access to cheaper food.

在关闭的发电厂下风处种植玉米的农民的产量增加了7%，他们将是主要的受益者。然而，Metaxoglou计算出，供应增加导致的价格下跌实际上意味着农民损失了钱。然而，消费者现在可以买到更便宜的食物。

Corn and soy are included in so many processed foods, far beyond the obvious tortillas and tofu, that the effect would be exceptionally dispersed. Consumers wouldn't have noticed the fall (or slower rise) in the price of their groceries as a result of this effect, but that doesn't mean it wasn't there every time they reached the till.

玉米和大豆被包含在如此多的加工食品中，远远超出了显而易见的玉米饼和豆腐，以至于其影响将被特别分散。由于这种影响，消费者不会注意到食品价格的下跌(或缓慢上涨)，但这并不意味着他们每次到收银台时都能看到这种情况。

“Our findings show that reducing NOx and other harmful emissions from power plants is beneficial not only for human health, but also for agriculture production,” Metaxoglou said in an emailed statement.

Metaxoglou在一份电子邮件声明中说:“我们的发现表明，减少发电厂的氮氧化物和其他有害排放不仅有利于人类健康，也有利于农业生产。”

Around half of coal's decline has been from competition with gas, but the other half is a result of rising solar and wind production. Opponents of climate action love to bemoan the effect of renewable energy subsidies on poorer consumers' electricity bills, but all that cost and more comes back in less obvious ways.

煤炭产量下降的原因中，约有一半来自与天然气的竞争，而另一半则是太阳能和风能产量上升的结果。气候行动的反对者喜欢抱怨可再生能源补贴对较贫穷的消费者电费的影响，但所有这些成本和更多成本都以不那么明显的方式回来了。