250 Meter High Channel Hundreds of Kilometers Long Discovered Underneath Antarctic Ice Shelf

Credit: MODIS Mosaic of Antarctica (MOA) Image Map / Anne le Brocq.

An ice channel stretching hundreds of kilometers and reaching as high as 250 meters have been discovered under a floating ice shelf in Antarctica. The ice shelf was discovered using satellite image and radar measurements from the sky. Based on the data recorded, the channel is as tall as the Eiffel tower.

The image map from the MODIS Mosaic of Antarctica (see image above) shows the ice shelf channel as it aligns the flow route of the water under the ice sheet and the start of the ice shelf cannel. The dashed line marks the border where the ice leaves solid ground and starts to float on the ocean surface.

Ice shelves are thick platforms of ice 100 to 1000 meters thick that forms where a glacier or ice sheet flows down to a coastline and onto the ocean surface; similar to a pier or a dock. These can only be found in Antarctica, Greenland and Canada.

Around 44% of the ice shelves are connected to the Antarctic coastline covering an area of 1,541,700 km². In the image map above, the part of the ice sheet between the grounded ice (part of the ice shelf that rests on bedrock) and the floating shelf (on the ocean surface) is called the grounding line.