The Gulf Stream is in imminent danger of shutting down due to the disintegration of the Greenland Ice Sheet.
N.S.F. Summit
Chapter 31
N.S.F. Summit
Greenland
April 25, 2025
“Watching a glacier disintegrate is like visiting an old friend with a terminal illness, you have to have the strength to say goodbye. But I see this and say, ‘Oh man this is happening really fast.’”
Marco Tedesco
VW Road Russell, Greenland
July, 2024
Gregor woke in the middle of the night with a blinding headache.
He had flown to Greenland’s N.S.F.’s Summit station the day before where the resident doctor had warned him that newcomers often experienced altitude sickness.
“In most cases it only produces hangover-like symptoms, but on occasion it can result in brain swelling and death.”
“Oh great, and I forgot to ask how to tell the difference.”
In the morning a small group of ice scientists filled him in on the ropes, over breakfast.
“The first thing you have to know is to always refer to the station as N.S.F. Summit. That’s the rule. You also have to have a handler that follows you everywhere, but it’s OK, if you get separated, we will tell her you wandered off in the snow.”
“When I was covering the war in Ukraine, I also had a handler and we often wandered off alone.”
“Where is she now?”
“She is my wife, the beautiful Petra.”
“What a lovely name.”
“But tell me about the Summit.”
“N.S.F. Summit, remember.”
“OK, OK, N.S.F. Summit.”
“First, the Greenland ice sheet is in the shape of a dome, with N.S.F. Summit sitting on the very top. The ice below us is two miles thick. If we chopped up all this ice into one-inch cubes and stacked them on top of each other, they would reach Alpha Centauri, several light years away.”
“Or melt and inundate the world’s coasts under twenty feet of water.”
“Yes, admittedly the most likely scenario.
But since the nineteen-seventies the ice sheet has shed six trillion tons of ice and the loss is accelerating. Those of us who have spent our whole lives studying the ice sheet are shocked by how quickly this is all happening.”
“Frightening.”
“But also fascinating, the ice sheet’s glaciers are moving at non-glacial speeds and temperatures are rapidly rising. At the same time the ice sheet seems to be twisting and writhing like a snake.”
“I read that it rained at the station for the first time in history.”
“You read right. That was in 2021. But the most worrisome thing is that while we know that the future depends on how we react to human caused global warming, we found that the climate is also prone to its own sudden dramatic shifts.”
“How do you know that?”
“Follow me to the snow pit. Zoe Courville, our ice scientist from your Mount Washinton in New Hampshire, dug it to show visiting scientists the difference between summer and winter snow.
It is only seven feet deep but I expect even a journalist can see the difference between the grainy summer snow and the dense finer winter snow.”
“I can but how do you know the ice up here is two miles thick?”
“In the Nineteen Nineties one of our teams drilled from the top of the ice sheet all the way down to the bedrock and pulled up two miles worth of long skinny cylinders of ice.
Some of the ice came from snow that fell when Nero was emperor, and some came from during the reign of Tutankhamum. And, at the very bottom of the cores was snow that fell at the beginning of the last ice age.”
“Cool, and what do you do with ice cores?”
‘We have analyzed the cores with a mass spectrometer to calculate the average temperature of Greenland in any given year.”
“And what did you find?”
“We discovered that during the last ice age, Greenland was unimaginably cold with temperatures thirty degrees lower than today. But then for some reason that we don’t fully understand, the temperatures suddenly shoot up, only to drop again.”
“Interesting.”
“We are still struggling to make sense of all this data. The best theory we have is that these wild swings are set off by some daisy chain of feedbacks involving the ice, the air and most importantly AMOC.”
“I’ll bite, what’s AMOC?”
“The Atlantic Meridional Overturning Circulation, a fancy way of referring to what you civilians might call the Gulf Stream.”
“OK, I’ve heard of that.”
“What happens is that in the North Atlantic, cold salty water is so dense that it sinks to the bottom and snakes its way south. That draws warm surface water north in the Gulf Stream, where it cools and sinks again. So, the circulation is like a giant escalator.”
“And we only see the top of the escalator.”
“The Gulf Stream, exactly.
When AMOC is running full steam, the water circulates with a hundred times the flow of the Amazon River. The consensus among scientists is that AMOC collapsed repeatedly during the last ice age even though they are not exactly sure what triggered the collapse. But now we have evidence that AMOC is already slowing down and could fully shut down entirely between 2037 and 2064.”
“So, we are rapidly approaching the point of no return.”
“Yes, watching the glaciers disintegrate is like visiting an old friend with a terminal illness, you have to have the strength to say goodbye. You see this and say, ‘Oh man this is happening really fast.’
When I see tourists flying carbon spewing jets up here to see the glaciers before they disappear, I want to tell them, it is like shooting the last passenger pigeon before it goes extinct … but I usually don’t.”