Saturday, June 29, 2024

New Sobering Studies about Antartica's Melting Ice


It was only two years ago that studies of the infamous Thwaites Glacier, aka: the Doomsday Glacier located in West Antarctica, found rapid melting. At the time, scientists said it was “hanging on by its fingernails.” (Source: ‘Doomsday Glacier’ Which Could Raise Sea Level by Several Feet, is ‘Hanging by its Fingernails,’ Scientists Say, CNN, September 6, 2022)


Since that warning was issued the planet has vastly exceeded global warming expectations. A new study raises the bet on sea level rise, maybe by a lot. The study warns that the Antarctic ice sheet is melting in a “new, worrying way” that scientific models of sea level rise have failed to account for. (Source: Alexander T. Bradley, et al, Tipping Point in Ice-Sheet Grounding-Zone Melting Due to Ocean Water Intrusion, Nature Geoscience, 2024)


British Antarctic Survey scientists discovered warm ocean water seeping beneath the ice sheet down to the grounding line, which is where the ice rises from the seabed and starts to float. Moreover, adding another dimension, new studies show that small increases in ocean temperatures can have big impact on melting. 


These new facts raise very serious concerns about all projections of sea level rise. Moreover, ocean temperatures have been setting new records. “The ocean has now broken temperature records every day for more than a year.” (Source: The Ocean Has Shattered Records for More Than a Year, The New York Times, April 10, 2024)


Making matters more edgy yet, a 2,000-foot-long ice core removed from West Antarctica looks like a game-changer. And it’s not pretty. (Source: Mackenzie M. Grieman, et al, Abrupt Holocene Ice Loss Due to Thinning and Underground in the Weddell Sea Embayment, Nature Geoscience, Feb. 8, 2024)

The 2,000-foot-long ice core is the first paleoclimatic proof that the Antarctic ice sheet can melt very fast in a relatively short period of time.


Under circumstances somewhat like today, but 8,000 years ago, part of the ice sheet melted by 450 meters (1,476 feet, or higher than the Empire State Bldg.) over a period of only 200 years, which was at the end of the last ice age. 


According to Eric Wolff, glaciologist at University of Cambridge/UK: “We’ve been able to say exactly when it retreated, but we’ve also been able to say how fast it retreated.” (Source: Scientists Discover an Alarming Change in Antarctica’s Past That Could Spell Devasting Future Sea Level Rise, CNN, February 8, 2024)


According to the scientists, in today’s world: “If it does start to retreat, it really will do it very fast.” And of course, the concern is not only 1,476 feet of ice melt over 200 years, but also, and more importantly, what will be the sea level impact of the initial several feet over upcoming decades, assuming a repeat of what occurred 8,000 years ago, which, so far, knock on wood, does not look to have started, yet. But West Antarctica is not going to make a pre-announcement that it’s ready to commence a cascading meltdown!


According to Ted Scambos, glaciologist, Univeristy of Colorado, Boulder: “The amount of ice stored in Antarctica can change very quickly— at a pace that would be hard to deal with for many coastal cities,” Ibid.


The Grieman, et al detailed study of the 8,000-year-old ice core revealed the biggest surprise in recent memory: Antarctic ice meltdowns can happen much faster than current sea level studies assume. According to Wolff: “We actually spent a lot of time checking that we hadn’t made a mistake with the analysis,” Ibid.


Wolff warns that it is crucial to take all measures possible to tackle climate change to avoid “these tipping points.” We do not want the same 1,476-foot ice meltdown to start again at such an alarming rate. 


The point is: It already happened under similar circumstances as today so it’s an understatement that nation/states should react as soon as possible and take all measures possible to mitigate climate change/global warming.


The most recent National Oceanic and Atmospheric Administration report highlights concerns: The month of May had a record-high monthly global ocean surface temperature for the 14th consecutive month. The ocean-only temperature for May in the Southern Hemisphere ranked the highest on record.


“Over the past 50 years, the west coast of the Antarctic Peninsula has been one of the most rapidly warming parts of the planet. And it has been established that Antarctic Circumpolar Current is warming more rapidly than the global ocean as a whole.” (Source: Impacts of Climate Change, Discovery Antarctica)


Assuming nation/states fail to take enough measures soon enough to mitigate global warming, which increasingly looks likely, a significant issue arises: When should sea walls be built and how high will be high enough?  


-Robert Hunziker lives in Los Angeles and can be reached at rlhunziker@gmail.com.   

Image by Torsten Dederichs    

from CounterPunch




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