Monday, February 13, 2023

An Unexpected Climate Change issue

Most of the effects of Climate Change has been known or projected for a long time. Most of them at least 40 years.

But a new and previously unknown threat has emerged. And, as you might of guessed, it was worse than we thought. Rarely does new climate news turn out to be good news.

So here's the thing. Back in the early 1980s we were working with state of the art scientific tools. Our tools in the 2020s are much better and complete. And we have found issues in the Antarctic.

Antarctic has actually been less effected by Climate Change to date than the Arctic. We have seen the loss of Sea Ice in the Arctic. And we see the interlink effects. Sea Ice reflects the suns rays back to the sky. Where as blue seas absorb more heat. Around the arctic, melting of the permafrost in Russia, Alaska and Canada ends up release more methane, a very powerful greenhouse grass.

And many people were looking at the Antarctic and being happily surprised by the loss of ice to date. And then scientists looked down, under the water. They were not so happily surprised. It turns out that most warming in the Antarctic is in the ocean. Why is that bad?

There are two relatively small glaciers that essentially hold back the massive West Antarctica glacier system - Pine Island and Thwaites Glacial Tongue. They was these systems hold back the system is that they are both anchored to the bedrock under the ocean floor, which makes their areas stable, and is holding back the large system.

It turns out this system is failing and collapse is a possibility. Climate Change is heating the water of the Antarctic Ocean, which is being pushed by the currents to go under ice shelfs. In the case of these two sites, the glaciers are being quickly undermined. If they both are floated off the bedrock and removed from the front of the Antarctic West Glacier Fields, there is nothing holding them back from traveling downhill and entering the ocean. This will seriously raise sea levels. 

The new hope - and hope is the word as we don't understand enough - that the glacial collapse we be slow (in human terms  - glacial terms it is Formula 1 fast). Greenlands glaciers are moving much faster than in history, but there has been no collapse yet. Hopefully Antarctica will act in the same way. But fast or slow, the sea level rise will be centuries earlier than we thought.


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