Australian Antarctic Division glaciologist Neal Young says satellite images show the new iceberg broke off the Mertz Glacier Tongue in mid-February.

The unnamed chunk is about the size of Luxembourg or Hong Kong, and could possibly impact ocean currents that control the weather, French oceanographers cautioned.

The Laboratory for Geophysics and Oceanographic Space Research in Toulouse said that while the impact would not be felt for decades or longer, a decrease in the production of colder, dense water around the two icebergs could eventually result in less temperate winters in the North Atlantic.

Glaciologist Benoit Legresy said that if the icebergs move east and run aground, or drift northward into warmer waters, they will have no impact on currents.

But if they stay in this area -- which is likely -- they could block the production of this dense water, essentially putting a lid on the polynya (ice-free water around Antarctica),” Legresy explained.

The iceberg involved in the collision (B09B) broke off itself in 1987. It then became jammed up against Antarctica for more than 20 years before starting a slow-motion battering movement responsible for the new iceberg.

Images: NASA