万物简史 第370期:进入对流层(11)

 What we do know is that because heat from the Sun is unevenly¹ distributed, differences in air pressure arise on the planet. Air can't abide² this, so it rushes around trying to equalize things everywhere. Wind is simply the air's way of trying to keep things in balance. Air always flows from areas of high pressure to areas of low pressure (as you would expect; think of anything with air under pressure—a balloon or an air tank—and think how insistently³ that pressured air wants to get someplace else), and the greater the discrepancy⁴ in pressures the faster the wind blows.

我们知道的是，太阳的热量分布不匀，形成了本行星上的不同气压。空气无法容忍这种状态，于是就横冲直撞，想要实现处处平衡。风就是空气想要实现这样的平衡的一种办法。空气总是从高压地带向低压地带流动（你会料到这一点。想像一个含有压缩空气的任何东西——一个气球，或一个气罐，或一架没有窗户的飞机，想像一下压缩空气如何老是想去别处）。压力相差越大，风的速度就越快。

Incidentally, wind speeds, like most things that accumulate, grow exponentially, so a wind blowing at two hundred miles an hour is not simply ten times stronger than a wind blowing at twenty miles an hour, but a hundred times stronger—and hence that much more destructive. Introduce several million tons of air to this accelerator effect and the result can be exceedingly energetic. A tropical hurricane can release in twenty-four hours as much energy as a rich, medium-sized nation like Britain or France uses in a year.

顺便说一句，风速像大多数累积的东西一样，是以指数来增长的，因此以每小时300公里的速度刮的风，不是比以每小时30公里的速度刮的风强10倍，而是强100倍——因此它的破坏性也要大得多。要是将几百万吨空气加速到这种程度，就能产生极其巨大的能量。一场热带飓风在24小时里所释放的能量。相当于像英国或法国这样一个富裕的中等国家一年所使用的能量。

The impulse of the atmosphere to seek equilibrium⁵ was first suspected by Edmond Halley—the man who was everywhere—and elaborated upon in the eighteenth century by his fellow Briton George Hadley, who saw that rising and falling columns of air tended to produce "cells" (known ever since as "Hadley cells").

大气寻求平衡的干劲，是由埃德蒙·哈雷首先发现的——他是个无处不在的人物，并由他的英国同胞乔治·哈德利在18世纪加以阐述。哈德利注意到，上升和下降的气柱往往会产生“环流”（自那以后一直被称之为哈德利环流）。

1 unevenly   

adv.不均匀的

参考例句：

• Fuel resources are very unevenly distributed. 燃料资源分布很不均匀。
• The cloth is dyed unevenly. 布染花了。

2 abide   

vi.遵守；坚持；vt.忍受

参考例句：

• You must abide by the results of your mistakes.你必须承担你的错误所造成的后果。
• If you join the club,you have to abide by its rules.如果你参加俱乐部，你就得遵守它的规章。

3 insistently   

ad.坚持地

参考例句：

• Still Rhett did not look at her. His eyes were bent insistently on Melanie's white face. 瑞德还是看也不看她，他的眼睛死死地盯着媚兰苍白的脸。
• These are the questions which we should think and explore insistently. 怎样实现这一主体性等问题仍要求我们不断思考、探索。

4 discrepancy   

n.不同；不符；差异；矛盾

参考例句：

• The discrepancy in their ages seemed not to matter.他们之间年龄的差异似乎没有多大关系。
• There was a discrepancy in the two reports of the accident.关于那次事故的两则报道有不一致之处。

5 equilibrium   

n.平衡，均衡，相称，均势，平静

参考例句：

• Change in the world around us disturbs our inner equilibrium.我们周围世界的变化扰乱了我们内心的平静。
• This is best expressed in the form of an equilibrium constant.这最好用平衡常数的形式来表示。