Climatide

Courtesy of Prof. Andreas Muenchow, University of Delaware

Satellite image of the massive ice island that recently broke off Greenland’s Petermann Glacier.

It has been 35 years (and one day) since the publication of the Science paper in which Columbia University’s Wally Broeker first coined the term ‘global warming.’ As Broeker reveals in an interview with NPR’s Guy Raz, that article didn’t make the kind of splash that you might expect of the naming of arguably the greatest challenge facing humanity today. Then again, Mozart and DaVinci probably didn’t garner international attention on the days of their births either. Global warming (or ‘climate change,’ as it prefers to be called these days) is all grown up now, and what better way to mark the anniversary than the birth of the largest ice island in almost fifty years.

“In the early morning hours of August 5, 2010, an ice island four times the size of Manhattan was born in northern Greenland,” said Andreas Muenchow of the University of Delaware. Greenland’s Petermann Glacier lost about a quarter of its floating ice-shelf when it calved the approximately 100 square mile island. Muenchow told NPR he can’t say with certainty that climate change caused this particular event, but Greenland’s ice sheets are calving islands with increasing frequency.

The ice was already floating so it won’t contribute directly to rising sea level. But as it melts, it will add a huge volume of fresh water to the North Atlantic – enough to supply the entire U.S. with tap water for four months. Worst-case scenarios from computer models of ocean currents suggest that cold, fresh water from melting glaciers could completely rearrange or shut down the interconnected system of ocean currents known as the ‘ocean conveyer belt’ (another concept that traces it’s roots to Wally Broeker, incidentally). The result would be rapid, dramatic climate change. Areas like North America and northern Europe, which are warmed by the Gulf Stream, would very quickly become much colder.