Sunday, August 8, 2010

Striped Icebergs

Icebergs in Lake Michigan sometimes have stripes, formed by layers of snow, that react to different conditions.

Blue stripes are often created when a crevice in the ice sheet fills up with melted water and freezes so quickly that no bubbles form.

When an iceberg falls into the lake, a layer of water can freeze to the underside. If this is rich in algae, it can form a green stripe.

Brown, black and yellow lines are caused by sediment, picked up when the ice sheet grinds downhill towards the lake. The water froze the instant the wave broke through the ice.

That's what it is like in Lake Michigan where it has been some of the coldest weather in decades. Water freezes the instant it comes in contact with the air. The temperature of the water is already some degrees below freezing. Just look at how the wave froze in mid-air...

Nature is truly awesome. Global warming is not so awesome but it's affects are phenomenal.

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