James Hansen says that the melt rate of Greenland's Ice sheet is doubling every ten, or even every 5 years. Thermohaline circulation in the Atlantic is expected to slow by 2075 as a result. Atlantic Ocean storms may intensify due to more cold water staying on the surface in the north Atlantic while the south Atlantiac continues to heat up, creating a stronger gradient.
Greenland ice melting at an expanding pace may begin cooling the North Atlantic and increasing the severity of storms by 2075, said James Hansen, the former NASA scientist who raised concerns about global warming in the 1980s.
“If we stay on this path where the rate of mass loss from Greenland doubles every 10 years, we would get to a situation by about 2075 or 2080 where the mass loss is so fast that it causes the whole North Atlantic to be colder,” Hansen said in London.
The findings are from computer models using current rates of ice melt and will be detailed in a paper that Hansen plans to finish writing in the summer, he said on Thursday in an interview.
Inflows of cold, fresh water from Greenland would slow deep currents that carry cold water south, cooling the North Atlantic as tropical waters get warmer, Hansen said. That would increase a “temperature gradient” that’s conducive to stronger storms.
“It could happen sooner” than 2075, Hansen said. “If you look at how fast the mass loss is increasing, it looks like the doubling time is between five and 10 years.”
The findings add to research showing the system of Atlantic currents that channels the warm Gulf Stream to the northeast and moves colder, deeper waters south may slow this century because of climate change. [emphasis mine]
This April 20, 2013 NASA handout image shows Saunders Island and Wolstenholme Fjord with Kap Atholl in the background seen during an IceBridge survey flight nea Qaasuitsup, Greenland. Sea ice coverage in the fjord ranges from thicker, white ice seen in the background, to thinner grease ice and leads showing open ocean water in the foreground.