By Robert Krulwich
It was three, maybe four o’clock in the morning when he first saw them. Grad student Jeff Bowman was on the deck of a ship; he and a University of Washington biology team were on their way back from the North Pole. It was cold outside, the temperature had just dropped, and as the dawn broke, he could see a few, then more, then even more of these little flowery things, growing on the frozen sea.
“I was absolutely astounded,” he says. They were little protrusions of ice, delicate, like snowflakes. They began growing in the dry, cold air “like a meadow spreading off in all directions. Every available surface was covered with them.” What are they?
“Frost flowers,” he was told. “I’d never heard of them,” Jeff says, “but they were everywhere.”
They aren’t flowers, of course. They are more like ice sculptures that grow on the border between the sea and air. On Sept. 2, 2009, the day Jeff’s colleague Matthias Wietz took these pictures, the air was extremely cold and extremely dry, colder than the ocean surface. When the air gets that different from the sea, the dryness pulls moisture off little bumps in the ice, bits of ice vaporize, the air gets humid — but only for a while. The cold makes water vapor heavy. The air wants to release that excess weight, so crystal by crystal, air turns back into ice, creating delicate, feathery tendrils that reach sometimes two, three inches high, like giant snowflakes. The sea, literally, blossoms.