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Climate Brief: East Antarctica's Conger Ice Shelf is gone.

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According to reporting by The Guardian, the entirety of the Conger ice shelf in East Antarctica has collapsed over a couple of days.

An ice shelf is the marine extension of a land-based glacier, and it works like a cork in a bottle holding the land ice in place as not to add to sea-level rise from land ice. These ice shelves dominate West Antarctica, but they are rare in the eastern part of the continent as most of the ice of a glacier is on land. East Antarctica has been considered stable, but the past couple of weeks has shocked scientists on a couple of fronts.

NASA planetary scientist and Woods Hole National Oceanographic Institution Dr. Catherine Colello Walker is quoted in the article describing the event as "one of the most significant collapse events anywhere in Antarctica since the early 2000s when the Larsen B ice shelf disintegrated". Larsen B collapsed on the peninsular Antarctic in 2002 due primarily to surface melting. Because the Conger ice platform is nowhere near as enormous (comparable in size only to New York City) as other glaciers such as Totten and Thwaites, its effect on the sea-level rise will be minimal. 

The US National Ice Center confirmed the collapse of Conger, but two smaller icebergs calved from the Totten glacier and the Glenzer ice shelf, also located in East Antarctica. Conger and Glenzer are adjacent to each other, and both have had their ice underbelly tunneled out by the upwelling of wind-driven warm ocean water. But it is believed the extraordinary warming of East Antarctica by last week's record-breaking atmospheric river with heavy rainfall was the likely trigger for the weakened ice to collapse. 

The long term demise and eventual collapse of Conger ice shelf in East Antarctica 🇦🇶 as observed by @CopernicusEU#sentinel1🛰️ pic.twitter.com/z78KGokTna

— Stef Lhermitte (@StefLhermitte) March 25, 2022

The Conger ice shelf had been shrinking since the mid-2000s, but only gradually until the beginning of 2020, Walker said. By 4 March this year, the ice shelf appeared to have lost more than half its surface area compared to January measurements of around 1,200 sq km.

Peter Neff, a glaciologist and assistant research professor at the University of Minnesota, said that to see even a small ice shelf collapse in East Antarctica was a surprise.

“We still treat East Antarctica like this massive, high, dry, cold and immovable ice cube,” he said. “Current understanding largely suggests you can’t get the same rapid rates of ice loss [as in West Antarctica] due to the geometry of the ice and bedrock there.”

“This collapse, especially if tied to the extreme heat brought by the mid-March atmospheric river event, will drive additional research into these processes in the region.”

Satellite data from the Copernicus Sentinel-1 mission showed that movement of the ice shelf began between 5 and 7 March, Neff said.

By the way, the Totten glacier holds 11 feet of sea-level rise. Thwaites is nicknamed the Doomsday Glacier due to its likely near-term collapse, while Totten is called the Sleeping Giant because the wind eats away at it by upwelling warm ocean water. 

Here's how wind-driven upwelling affects Totten Ice Shelf. pic.twitter.com/urJNYll83D

— Chad A. Greene (@chadagreene) November 1, 2017

An exceptional #heatwave hit #Antarctica🇦🇶 last week Temperature anomalies reached 40°C above average in the east of the continent ⬇️The effects of abnormal temperatures and 🌧️ at Totten Glacier, as seen by #Copernicus#Sentinel1🇪🇺🛰️on 6 (before) and 18 March (after the ♨️) pic.twitter.com/ADwMip3bvI

— Copernicus EU (@CopernicusEU) March 23, 2022

We Don't Talk About Collapse To Revel In It; We Talk About Collapse to Prevent It

Those dismissing us all as doom-and-gloomers hoping for collapse have it backward: yes, some long for collapse as a real-life disaster movie, but those discussing collapse in systems terms are trying to avoid it, not revel in it.

If the system is vulnerable beneath a surface stability, then the only way to avoid negative consequences is to understand those vulnerabilities / fragilities and work out systemic changes that reduce those risks.

It’s not the analysis of vulnerabilities that causes collapse, it’s refusing to look at vulnerabilities because to do so is considered negative. Why not be optimistic and just go with the consensus that the status quo is impervious to serious disruption? Can-do optimism is all that’s needed to overcome any spot of bother.

The problem is humanity’s propensity to confuse optimism with magical thinking. This confusion is particularly visible in any discussion of energy. The status quo holds that every problem has a technological solution, and doubting this optimism is dismissed as naysaying: “why can’t you be positive?”

It's right there above you—just look up.


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