William Colgan, a Canadian senior researcher with the Geological Survey of Denmark in Greenland, recently remarked on a study published in Nature that found the Greenland ice sheet is losing twenty percent more ice than previously thought. An area roughly the size of 2,000 square miles of ice has been lost at the margins of the ice sheet since 1985. What the study did not take into account was the inland meltwater that drains into the ocean. Amazingly, inland meltwater from Greenland is not considered in any oceanographic model, as reported by the Guardian.
The most recent update from a project that collates all the other measurements of Greenland’s ice found that 221bn tonnes of ice had been lost every year since 2003. The new study adds another 43bn tonnes a year, making the total loss about 30m tonnes an hour on average.
The scientists said: “There is some concern that any small source of freshwater may serve as a ‘tipping point’ that could trigger a full-scale collapse of the Amoc, disrupting global weather patterns, ecosystems and global food security. Yet freshwater from the glacier retreat of Greenland is not included in oceanographic models at present.” The influx of less dense freshwater into the sea slows the usual process of heavier salty water sinking in the polar region and driving the Amoc.
William Colgan shed light on the effect of meltwater on the AMOC and marine biodiversity, but I was unaware of his statement on gravity. (He is the only one I have found who pointed this out from the decades-long underestimation of Greenland ice.) Massive ice loss weakens Greenland’s gravity.
Matt Galloway (MG) of CBC News interviewed William Colgan (WC) recently (the audio file is here). Colgan stated a mind-boggling truth that is not common knowledge within scientific communities or among many climate activists.
From the interview transcript:
MG: The ice isn't disappearing. I mean, it turns into water. The water has to go somewhere. So, when it ends up in the oceans, what does that mean?
WC: Oh, boy. It's pretty complicated, actually. So, Greenland is losing so much ice. In addition to the study that we're talking about today that just came out, this is... they're just talking about, 40 million tons of the floating ice at the edge of the ice sheet. But all together, the ice sheet is losing about five times more than that or about, you know, it's 9 or 10 thousand tons a second. And it's so much ice that the gravity is weakening over Greenland. And that has an impact on how the ocean is shaped.
MG: Sorry, the gravity is weakening over Greenland.
WC: Isn't that weird?
MG: Because the displacement is less?
WC: Well, the mass in Greenland is less.
MG: Yeah.
WC: And I mean, if you think of how the moon orbits Earth and it pulls a tide around with it. Greenland is a relatively massive object, and it holds sort of a permanent tide of water close to it. And so, as Greenland begins to get smaller, its gravity begins to get weaker, and that water that it holds tight begins to slosh away to faraway places in the world where the gravity is not weakening. So, the upshot is, is that when Greenland loses mass and dumps ice into the ocean, most of the sea level rise is felt in the Southern hemisphere. And on the flip side, when Antarctica loses mass and weakens its gravity. That's when the sea level is felt in the Northern hemisphere.
I occasionally share the words of Peter Brannen from his introduction in the Atlantic titled The Terrifying Warning Lurking in the Earth’s Ancient Rock Record.
We could be missing something Big.
We live on a wild planet, a wobbly, erupting, ocean-sloshed orb that careens around a giant thermonuclear explosion in the void. Big rocks whiz by overhead, and here on the Earth’s surface, whole continents crash together, rip apart, and occasionally turn inside out, killing nearly everything. Our planet is fickle. When the unseen tug of celestial bodies points Earth toward a new North Star, for instance, the shift in sunlight can dry up the Sahara, or fill it with hippopotamuses. Of more immediate interest today, a variation in the composition of the Earth’s atmosphere of as little as 0.1 percent has meant the difference between sweltering Arctic rainforests and a half mile of ice atop Boston. That negligible wisp of the air is carbon dioxide.
Since about the time of the American Civil War, CO2’s crucial role in warming the planet has been well understood. And not just based on mathematical models: The planet has run many experiments with different levels of atmospheric CO2. At some points in the Earth’s history, lots of CO2 has vented from the crust and leaped from the seas, and the planet has gotten warm. At others, lots of CO2 has been hidden away in the rocks and in the ocean’s depths, and the planet has gotten cold. The sea level, meanwhile, has tried to keep up—rising and falling over the ages, with coastlines racing out across the continental shelf, only to be drawn back in again. During the entire half-billion-year Phanerozoic eon of animal life, CO2 has been the primary driver of the Earth’s climate. And sometimes, when the planet has issued a truly titanic slug of CO2 into the atmosphere, things have gone horribly wrong.
Today, humans are injecting CO2 into the atmosphere at one of the fastest rates ever over this entire, near-eternal span. When hucksters tell you that the climate is always changing, they’re right, but that’s not the good news they think it is. “The climate system is an angry beast,” the late Columbia climate scientist Wally Broecker was fond of saying, “and we are poking it with sticks.”
The beast has only just begun to snarl. All of recorded human history—at only a few thousand years, a mere eyeblink in geologic time—has played out in perhaps the most stable climate window of the past 650,000 years. We have been shielded from the climate’s violence by our short civilizational memory, and our remarkably good fortune. But humanity’s ongoing chemistry experiment on our planet could push the climate well beyond those slim historical parameters, into a state it hasn’t seen in tens of millions of years, a world for which Homo sapiens did not evolve.
Colgan also mentioned that Greenland Glacier Jacobshavn is in serious trouble because of cracking. It is already the world's fastest-moving glacier, and one of its icebergs is believed to have sunk the Titanic.
"The crevasses are phenomenally large. They're 20 meters wide (65 feet) and five kilometers (3.1 miles) long and quite bottomless; they weren't there 20 years ago."I will prepare something on the hairline fractures and massive crevasses on the Greenland Ice Sheet. Stay tuned. I seemed to have found my second wind again.
Climate change may not be headlines anywhere anymore, but that doesn’t mean the climate system is not in a death spiral. Activists across the country need to not only defeat MAGA but destroy them and get rid of Trump’s Supreme picks as soon as possible.
There is *nothing* you care about that survives a 6-3 Republican court for a generation. Nothing. I don’t know how many times the Court has to prove that to people before liberals unify and act. Elie Mystal.