冰山是什麼顏色的？
Most people would say that icebergs are white, and most of them are. But did you know that icebergs can also be stunning shades of blue and green?
An iceberg looks white because the packed snow on its surface is full of tiny air bubbles and the edges of ice crystals. Together, these reflect all the colors of visible light equally, so we see white.
As more and more snow piles up on top of an iceberg, the air bubbles are squeezed, and small ice crystals grow together into larger grains. Underwater, the air bubbles are squeezed out completely. When light hits this dense, compressed ice, much of it travels deep inside. The ice absorbs colors with longer wavelengths, such as red and yellow, while colors with shorter wavelengths, like green and blue, are reflected back. This "leftover" blue-green light is what gives some icebergs their remarkable colors.
Algae also often grow on the underwater sides of icebergs, leaving beautiful green stripes in the ice. These are easy to see when an iceberg rolls over and parts that used to be underwater come to the surface.
大部分的人都會說冰山是白色的，而大多數的冰山也確實是白色的。可是你知道嗎？冰山也會呈現令人驚嘆的藍色和綠色。
冰山看起來是白色的，是因為它表面壓實的積雪裡充滿了細小的氣泡和冰晶的稜角。它們對所有顏色的可見光反射得一樣多，所以我們看到的是白色。
隨著冰山頂上積的雪越來越多，氣泡被擠壓，小冰晶也會長在一起，形成更大的顆粒。到了水面下，氣泡會被完全擠出去。當光照到這種緻密、壓實的冰上時，大部分的光會深深透進冰裡。冰會吸收波長較長的顏色，例如紅色和黃色，而波長較短的顏色，例如綠色和藍色，則被反射回來。正是這些「剩下來」的藍綠色光，讓有些冰山呈現出非常美麗的顏色。
另外，冰山泡在水下的那一面常常長著藻類，在冰裡留下漂亮的綠色條紋。當冰山翻轉過來，原本在水下的部分露出水面時，就很容易看到這些條紋。