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Doomsday Glacier in Antarctica Could Collapse Soon: New Research - Rolling Stonehttps://www.rollingstone.com/politics/politics-features/doomsday-glacier-thwaites-antarctica-climate-crisis-1273841/the West Antarctic ice sheet is one of the most important tipping points in the Earth’s climate system. If Thwaites Glacier collapses, it opens the door for the rest of the West Antarctic ice sheet to slide into the sea. Globally, 250 million people live within three feet of high tide lines. Ten feet of sea level rise would be a world-bending catastrophe. It’s not only goodbye Miami, but goodbye to virtually every low-lying coastal city in the world.
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Depending on various emissions scenarios in the latest Intergovernmental Panel on Climate Change report, we could have as little as one foot of sea level rise by the end of the century, or nearly six feet of sea level rise (of course, rising seas won’t stop in 2100, but that date has become a common benchmark). “The difference between those [models] is a lot of lives and money,” says Richard Alley, a glaciologist at Penn State University and one of the great ice scientists of our time. Alley adds: “The most likely place to generate [the worst scenario] is Thwaites.”
Or to put it more urgently: “If there is going to be a climate catastrophe,” Ohio State glaciologist Ian Howat once told me, “it’s probably going to start at Thwaites.”
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“We just don’t know what the upper boundary is for how fast this can happen,” Alley says. “We are dealing with an event that no human has ever witnessed before. We have no analog for this.”
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“The current divergence among model predictions is actually a good sign because it means that scientists are probing different parameterizations, representations of processes, and hypotheses,” writes Jeremy Bassis, a geophysicist at the University of Michigan. Bassis suggests not focusing so much on the long-term uncertainty and highlighting instead what scientists know about the next few decades. “The skill of models in predicting sea level change on decadal time scales is high, and we already have actionable projections on these time scales. We should be emphasizing that fact in discussions with community members, stakeholders, and decision-makers, so they can move ahead with important adaptation and mitigation planning.”
But in the long run, it is not clear that the dynamics of ice sheet collapse that are underway at Thwaites can be stopped. As glaciologist Eric Rignot put it in 2015, in Antarctica, “the fuse has been blown.” Even if we cut carbon emissions to zero tomorrow, warm water will continue to flow beneath the ice sheet for decades, destabilizing the ice and further pushing the glacier toward eventual collapse. This doesn’t means that cutting carbon pollution to zero isn’t an important goal — nothing, in fact, is more important or more urgent. “We may have a small safety margin in Antarctica, but not a large one,” says Alley. Even if the fuse is blown, cutting emissions fast could slow it all down to a millennium-long crack-up that will give us more time to adapt. One way or another, our future is written in ice.