New Video: Greenland “Starting to Slip”
July 29, 2013
Latest video for The Yale Forum on Climate Change & the Media, the first since returning from Greenland – includes interviews with Ice expert Alun Hubbard, who I met in Kangerlussuaq, as well as a snip from Richard Alley, at June’s Chapman conference in Granby, CO, and Jason Box, who spoke from our DarkSnowProject HQ in Sisimiut, in early July.
Takeaway – Greenland represents 22 feet of sea level rise, it’s moving faster than anyone thought it could just a few years ago, and there are processes occurring deep in the ice that may make even faster movement inevitable. According to Hubbard, we may we witnessing the deglaciation of a major ice sheet, with serious global implications.
Climate Denial Crock of the Week 
July 29, 2013 at 7:59 pm
This slippage is evident all around Greenland such as on Tracy Gletscher in the NW and Zachariae in the NE and the list could go on and on.
July 29, 2013 at 8:24 pm
I know that water is essentially injected into the glacier’s base forcing an ice quake and lift locally, but I was wondering if there was any research about what happens to the water after it reaches the bottom. In particular is there a jackhammer effect when the water refreezes or does it typically stay in a liquid state till it gets cost. Anyway if you can direct me to any information I would greatly appreciate it.
July 29, 2013 at 8:26 pm
That should be as it get to the the coast. Sorry I’m having a difficult time talking today.
July 29, 2013 at 9:13 pm
[…] Takeaway – Greenland represents 22 feet of sea level rise, it’s moving faster than anyone thought it could just a few years ago, and there are processes occurring deep in the ice that may make even faster inevitable. According to Hubbard, we may we witnessing the deglaciation of a major ice sheet, with serious global implications Source […]
July 29, 2013 at 9:36 pm
I’ve sometimes wondered if the melting and the lubrication of the base could accelerate to such a degree that an extraordinarily large portion of the ice sheet could slide into the sea at once – causing a coastal catastrophe world wide.
Does anyone know if this is even possible?
July 29, 2013 at 10:59 pm
ice experts weigh in – but I think the general idea is that there are a number of main outlet glaciers that flow out of fiords along the coast – previous numbers for how much ice could be lost focused on what the contraints of these outlet pathways were, ie friction from bottom and sides.
more recently, there is appreciation that a lot of loss is occurring just from flat-out runoff – meltwater just running off the ice sheet and being lost to streams, rivers etc
Such surface melt is not constrained by geography, and so, the “speed limit” for melt loss from the ice sheet may be much higher than thought, and observed darkening of the ice sheet accelerates this trend.
Not aware that anyone is concerned about huge masses slipping off, but there is concern about water from the sea reaching inland to below-sea-level zones – discussed here
July 29, 2013 at 11:17 pm
Thanks.
July 30, 2013 at 8:38 pm
Last point in the video is very interesting. I take it that means that sea level rise could start to force warm seawater under the ice sheet. So the idea of catastrophic failure in the future may NOT be out of the question.
July 30, 2013 at 12:52 am
My understanding is that the bottlenecks around the coast would prevent that from happening.
July 30, 2013 at 3:39 pm
Unless, of course, we discover a previously unknown phenomenon whereby huge ice sheets, whose temperatures have been raised closer and closer to melting points, decide to fracture horizontally, and shear off above the tops of those stabilizing mountains, and slide into the sea.
Nah – that’s impossible. Right?
July 30, 2013 at 4:08 pm
Yeah, I guess my question was not all that well thought out.
But I do think that as warming becomes more pronounce, portions of Greenland will certainly become much more dangerous – with raging, nearly lifeless rivers like the world has never seen.
July 30, 2013 at 6:47 pm
Thanks, Peter, you continue to do excellent work.
At some point there will be a phase change, where deglaciation accelerates and the water hurtles into the ocean. The models, as the speaker pointed out, are currently way behind observations.
What do current observations mean in terms of added projected sea level rise between now and 2100? I know this is a difficult question, and the answer will be a range, but I’d be interested in it.
July 30, 2013 at 7:23 pm
cautious scientists still won’t go out on a limb as to what Greenland is going to do in coming
decades. A lot may have to do with how the jet stream behaves – ie from 2007 to 2012, a large
ridge of warm air moved over Greenland in the summer, and accelerated melting. This year, that
did not happen, and melting was delayed – although will still be considerable.
Hansen has written that if Greenland melt continues on a 10 year doubling over coming
decades, that sea level rise will reach a meter by 2067, and 5 meters by end of century.
Scientists like Hubbard and Box would come down on the high side of estimates,
but there’s still a lot of “wait and see” out there.