Yaël: What are you doing outside, Don? It's about to rain.
Don: I'm setting out bottles.
Y: I can see that. But why?
D: For my new business venture. Bottled rainwater!
Y: As in living plastic bottles out in the rain and then selling them as health drinks?
D: Exactly! What could be more pure and fresher than what straight from the heavens!
Y: Maybe water from the a mountain stream!
D: You see any mount stream around here?
Y: Fine. But rainwater isn't exactly pure, Don. It's got a lot chemicals.
D: Like what?
Y: Well, even without industrial pollution, atmospheric carbon dioxide dissolved into clouds makes rainwater at least slightly acidic.
D: Oh!
Y: But here in Indiana, a rain is almost ten times more acidic than natural rainwater.
D: Why?
Y: Well, a lot of power plants and other factories that burn coal to make energy in this Midwestern state. Burning coal releases sulfur and nitrogen oxides into the atmosphere, which make rain more acidic.
D: That does sound good! What would happen if you drag a rainwater?
Y: Nothing! The acid content isn’t high enough to harm humans, and it doesn’t affect the taste of the water, either. But acid rain can damage lakes, streams, and harm trees at high elevations. Also, acid rain accelerates the decay of buildings, statues, and sculptures.
酸雨
Yaël: Don你在干嘛呢?這天都快下雨啦!
Don: 我在放瓶子。
Y: 我看得出來(lái)!你放瓶子有什么用呢?
D: 做新的投資啊。瓶裝雨水!
Y: 就像這樣子把生活塑料瓶放在雨中裝雨水,然后再把它們當(dāng)健康飲用水賣(mài)了?
D: 一點(diǎn)不差!還有什么水比從天上直接降下來(lái)的水更純凈更新鮮呢!
Y: 或許山泉水可以!
D: 那你在附近有看到山泉嗎?
Y: 好吧,是沒(méi)有。但是雨水絕不是那么純凈的。雨水中有許多化學(xué)物質(zhì)。
D: 比如說(shuō)?
Y: 嗯……即使是沒(méi)有工業(yè)污染,空氣中的二氧化碳被云層吸收也會(huì)使雨水呈弱酸性。
D: 噢!
Y: 但是,我們印第安納州雨水的酸性比天然雨水要高出整整十倍!
D: 這又是為什么啊?
Y: 在這個(gè)中西部城市,有許多的發(fā)電廠和其他的工廠都是靠燒煤來(lái)產(chǎn)能的。煤燃燒時(shí)會(huì)產(chǎn)生硫和氧化氮,揮發(fā)到大氣中,使這里的雨水呈較強(qiáng)的酸性。
D: 這個(gè)聽(tīng)起來(lái)確實(shí)很有道理!那如果人喝了這些酸性的雨水又會(huì)怎么樣呢?
Y: 那倒沒(méi)事。雨水的酸含量不高,不會(huì)對(duì)人體造成什么傷害,也不會(huì)影響水的味道。但是,酸雨會(huì)影響湖泊,溪流,以及高海拔地區(qū)的樹(shù)木植被。同時(shí),酸雨還會(huì)加快建筑物,雕像,雕塑等的腐蝕。