【英语时差8,16】冰川渐渐融化

 Ya?l: Hey Don, whatch'a doing?

Don: Booking a trip to Glacier¹ National Park. I want to go there before the glaciers² disappear.

Y: What do you mean?

D: Scientists predict that within twenty years the park's remaining glaciers will melt  away.

Y: Why?

D: Whether it's because of human industry or natural cycles, temperatures are rising. And when temperatures rise, glaciers melt.

Y: Forgive me for sounding insensitive, but so what? Glaciers are nice to look at, but what difference will it make if they melt?

D: Glaciers are more than just pretty pictures. They're the main sources for many rivers that people depend on for drinking water, irrigation, and hydroelectric power.

Y: So are rivers drying up?

D: Not yet, but the amount of glacier water affects a river's flow volume. The lower the flow volume the less water there is for drinking, power, and everything else people  depend on rivers for. Also, greater water volume helps dilute³ a river's chemical content. The less water a river has, the higher the chemical concentration⁴, which can      pollute a lake fed by the river.

Y: I didn't know that. But how about this...Higher temperatures mean that more water  will evaporate⁵ from the oceans, which means more precipitation, including snow. So maybe some glaciers will actually grow even though it's getting warmer.

D: Some scientists make that argument, but most don't buy it. Sure, some glaciers are growing temporarily thanks to unusual amounts of snow, but they're the exception⁶ to  the rule. Generally, glaciers grow when the amount of snow that melts in the summer is less than the amount that falls in the winter. Right now, more snow is melting than falling.

Y: I guess you should book that trip.  

1 glacier   

n.冰川，冰河

参考例句：

• The glacier calved a large iceberg.冰河崩解而形成一个大冰山。
• The upper surface of glacier is riven by crevasses.冰川的上表面已裂成冰隙。

2 glaciers   

冰河，冰川( glacier的名词复数 )

参考例句：

• Glaciers gouged out valleys from the hills. 冰川把丘陵地带冲出一条条山谷。
• It has ice and snow glaciers, rainforests and beautiful mountains. 既有冰川，又有雨林和秀丽的山峰。 来自英语晨读30分（高一）

3 dilute   

vt.稀释，冲淡；adj.稀释的，冲淡的

参考例句：

• The water will dilute the wine.水能使酒变淡。
• Zinc displaces the hydrogen of dilute acids.锌置换了稀酸中的氢。

4 concentration   

n.集中；专注；浓度；浓缩

参考例句：

• She wrinkled her brows in concentration.她蹙额皱眉，陷入沉思。
• If smoke is going that way,then it means the concentration here should be decreasing.如果烟雾沿着这个方向飘，这意味着，这里的浓度应该是减少的。

5 evaporate   

vi.蒸发，挥发，消失；vt.使蒸发，使挥发

参考例句：

• Clearly,the star wars problem was not going to evaporate.显然，星球大战问题并没有不了了之。
• It will evaporate like a spirit.它将来总要像幽灵一样化成云烟。

6 exception   

n.例外,除外

参考例句：

• Everyone should keep discipline and you are no exception. 每个人都应该遵守纪律,你也毫无例外。
• There's an exception to every rule. 每项规则均有例外。