the The world’s largest iceberg A23aIt’s about three times the size of New York City, and weighs about a trillion tons, CBS partner BBC News reports, citing data from the European Space Agency (ESA). Using data from the agency’s CryoSat-2 mission, a spacecraft carrying a type of radar capable of sensing how much mass of an iceberg is above water, scientists were able to obtain information about how much mass is underwater.

A23a broke away from Antarctica in 1986 and became stuck almost immediately after a deep portion of it became lodged on the sea floor. Recently, it has been displaced and has begun to drift again.

“Over the past decade, we have seen a steady decline of 2.5 meters (about 8 feet) per year in sea fish, which is what you would expect given the water temperatures in the Weddell Sea,” said Andy Ridout, a University College London scientist and scientist at University College London. The Natural Environment Research Council’s Center for Polar Observation and Modeling told CBS News partner BBC News.

As it moves again, it is still unclear where winds and ocean currents will carry A23a. The huge iceberg has reached the tip of the Antarctic Peninsula, where a number of different currents meet.

The BBC said it is expected to drift through an area known as “Iceberg Alley,” and its path will affect any part of the ocean and ocean floor it travels over.

Mike Meredith, a professor at the British Antarctic Survey, told the BBC that icebergs were “responsible for very deep mixing of seawater”.

“They stir up ocean water, bring nutrients to the surface, and of course, they also drop a lot of dust. All of this will fertilize the ocean. You’ll often see phytoplankton thriving in their wake.”