Dry ice and sea smoke

Today I overheard a conversation while I was on a shuttle bus from Toronto Airport to downtown Toronto. We went along Lake Ontario in the -15C temperature, and the bus driver told the other two passengers about the "dry ice effect" on the water surface. It took me a while to realise that he was talking about sea smoke. In very cold winter (e.g. < -15C in Halifax), there is fog on the surface of warm water.  (I think it looks more like steam rather than fog because it rises quite fast into the air.) This is caused by moisture condensation, and is called sea smoke. On second thought, this is exactly the same physical effect of "steam" around dry ice. Well I guess this is another way to explain what is sea smoke!

3 則留言:

  1. 其實係咪簡單一點就是蒸發呢?

  2. 是蒸發,不過空氣中的水份一接觸冷空氣就立刻凝固成霧狀,所以看上去很以水滾,不過全個海面都像煲滾了一樣水氣不斷升上來,這點與沒有怎樣活動的霧不同,所以更似乾冰。

  3. 四年後更正:不是蒸發(evaporation),因為蒸發出來的是水氣,氣態的 H20。Sea smoke 是小水珠,如霧一樣是液態的 H20 ,甚至乎是小冰粒。