《那些古怪又讓人憂心的問題》第95期:把海水抽乾(1)
DRAIN THE OCEANS
Q. How quickly would the oceans drain if a circular portal 10 meters in radius leading into space were created at the bottom of Challenger Deep, the deepest spot in the ocean? How would the Earth change as the water was being drained?
Q．如果在海底最深處——挑戰者深淵——挖一個半徑10米且通向太空的圓形傳送門，那麼海水會以多快的速度漏出去？海水一點點被抽乾了，地球又是怎樣一番景象呢？——Ted M
——特德•M
A. I WANT TO GET one thing out of the way first:
A．首先說一點。According to my rough calculations, if an aircraft carrier sank and got stuck against the drain, the pressure would easily be enough to fold it up and suck it through. Cooool.
我粗略地估算了下，如果航空母艦沉沒了而且又恰好卡在這個排水口，那麼洞口處的壓強足以輕鬆將其折斷，然後把它吸進去。哈哈哈哈！Just how far away is this portal? If we put it near the Earth, the ocean would just fall back down into the atmosphere. As it fell, it would heat up and turn to steam, which would condense and fall right back into the ocean as rain. The energy input into the atmosphere alone would also wreak all kinds of havoc with our climate, as would the huge clouds of high-altitude steam.
那你要把洞的另一頭放在那裏呢？如果它太靠近地球，那麼海水又會掉回大氣層。在海水下落的過程中，它的溫度會不斷升高，然後變成水蒸氣，而水蒸氣最後又會冷凝成雨，最後還是會落回海洋。只是在這個過程中，對大氣層的能量輸入足以徹底攪亂地球的氣候，這還沒考慮高空巨量水蒸氣帶來的後果呢。So let's put the ocean-dumping portal far away-say, on Mars. (In fact, I vote we put it directly above the Curiosity rover; that way, it will finally have incontrovertible evidence of liquid water on Mars's surface.)
所以我們得把洞的另一頭放得遠一點——比如放到火星上。（其實我很想把它放到“好奇號”火星探測器上面，這樣我們就終於能有火星存在液態水的確切證據了！）What happens to the Earth?
那地球上會發生什麼變化呢？Not much. It would actually take hundreds of thousands of years for the ocean to drain.
變化不大。事實上要等上幾十萬年海水纔會全部漏完。Even though the opening is wider than a basketball court, and the water is forced through at incredible speeds, the oceans are huge. When you started, the water level would drop by less than a centimeter per day.
雖然這個洞比籃球場還寬，而且海水將以極高的速度從這個洞流出去，但是記住海水是非常非常多的。一開始，海平面每天下降的高度不會超過1釐米。There wouldn't even be a cool whirlpool at the surface-the opening is too small and the ocean is too deep. (It's the same reason you don't get a whirlpool in the bathtub until the water is more than halfway drained.)
而且海面上還不會出現酷炫的漩渦——因爲洞太小了，大海太深了。（這也是爲什麼浴缸裏的水在剛開始流出去時不會產生漩渦，至少要等一半的水流出去時纔會有。）But let's suppose we speed up the draining by opening more drains,1 so the water level starts to drop more quickly.
但不妨假設爲了讓水漏得更快些，我們喪心病狂地挖了更多的洞。1Let's take a look at how the map would change.
然後我們來看看世界地圖會發生怎樣的變化。
