18 March, 2001

Green Ice March 18

-066 51 Lat / 069 37 E Long

Since we had entered the Amery Ice Shelf area weeks ago I had been on the lookout for the elusive green iceberg. Then as we were traveling down Iceberg Alley, Pat showed me off in the distance a mere speck in my binoculars. My quest was finally over. There it was seemingly hiding behind a larger icebergŠ a. Others and myself brought it to the attention of Captain Joe. Amy, our chief scientist, had just joined us on the bridge. Captain Joe said "Amy I think that berg over there is right were we want to do some surveying". "I agree", Amy replied. Within moments the ship was abuzz trying to let everyone know about our find.

The view became more spectacular the closer we went. The green was jade in color with parts so clear it was translucent. We circled the berg to get a better view. I had a hard time filming as the sight before me was breath taking beyond anything I could imagine. I made a point to put the camera down and enjoy this rare treasure of nature. The temperature was below freezing and the wind bit through us. But I stayed out moving with the ship to find protection from the wind. Just as quickly as we had arrived we left to continue our surveying leaving the green berg a distant memory. Several times we came upon other green bergs but none compared to this one.

I had mentioned briefly before that green icebergs are green from organic material that has degraded from marine plants and animals. Because glacial ice is less dense than seawater 90 percent of the ice shelf is below water. This can reach upwards of 450 meters under the water. At that depth seawater slowly freezes to the underside of the ice shelf, forming "marine ice." It is in that marine ice that organic materials can become frozen in with the glacial ice. Green icebergs are rarely seen because you have to have just the right conditions for them to form. To see the green ice the iceberg has to have turned over. This happens when uneven melting occurs leaving the top heavier than the bottom, causing the berg to list and eventually flip over exposing its green underbelly.