評(píng)論
打印
I'd like to look into your past, and predict the future.
我想看看你的過(guò)去,預(yù)測(cè)未來(lái)。
I bet that the last time you went to the beach, the wind was blowing in off the water.
我敢打賭，你最后一次去海灘的時(shí)候，海風(fēng)正從水面吹來(lái)。
Maybe it was just a pleasant breeze, maybe something a little stronger.
或許是令人愉快的微風(fēng)，也或許是更強(qiáng)一點(diǎn)的風(fēng)。
But it was definitely coming in off the water.
但是它的確來(lái)自于水面，
What's more, a breeze will be coming in off the water the next time you go to the beach.
更重要的是，你下次去海灘的時(shí)候微風(fēng)又會(huì)徐徐吹來(lái)。
How do I know? Easy.
我為什么會(huì)知道？答案很簡(jiǎn)單。
Wind is caused by differences in the temperature of air.
風(fēng)是由空氣的溫差引起的。
If you have a lot of hot air in one location and a lot of cold air next to it, the line where they meet will be windy.
如果一個(gè)地方有大量的熱空氣，它的旁邊又有大量的冷空氣，那么冷熱空氣相交的地方就會(huì)形成風(fēng)。
That's because the hot air is rising and the cold air is rushing in to fill the space left behind. Whoosh!
因?yàn)闊峥諝馍仙淇諝饩蜁?huì)迅速?zèng)_到熱空氣留下的位置里并填滿整個(gè)空間。
Now, here we are at the beach.
現(xiàn)在我們站在海灘上。
What do you notice?
你注意到了什么？
Well, the sand under your feet retains heat pretty effectively.
你腳下的沙子能夠有效的保持熱量。
Once it is hot, it stays hot.
一旦它變熱了，它就會(huì)維持熱度。
Not so for ocean water, which is much harder to heat.
可是海水卻很難變熱。
Think of how cold the water feels when you step into it off a hot beach.
想想當(dāng)你從水中踏入炙熱的沙灘時(shí)，會(huì)發(fā)現(xiàn)海水是多么的寒冷啊！
This distinction is true of land and sea in general.
總的來(lái)說(shuō)，這就是陸地和海洋的真實(shí)區(qū)別。
On a sunny, summer day, the land gets hotter, and stays hotter, than the sea.
陽(yáng)光明媚的日子，陸地比海洋要熱很多，
That means the air over the beach will be hotter than the air over the water.
那意味著海灘上空的空氣將會(huì)比水面上空的空氣熱，
And that means the air will be rising over the beach.
也就是說(shuō)海灘上的熱氣將會(huì)上升。
As the hot beach air rises up, the relatively cooler air over the water moves in to take its place.
隨著海灘上空熱空氣的上升，水面上相對(duì)寒冷的空氣就會(huì)流動(dòng)過(guò)來(lái)代替熱空氣的位置。
The result? A sunny day in summer creates its own breeze.
結(jié)果是什么呢？在夏天一個(gè)陽(yáng)光燦爛的日子里有微風(fēng)吹過(guò)。
