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[Music]

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we passed the point of no return and at

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this point would say it's just a matter

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of time before these glaciers completely

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disappear to see we've focused more on

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this particular sector of West

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Antarctica because this is where we see

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the most dynamic changes but we've been

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observing changes in speed the

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acceleration of these measures

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feeling of its relations and also the

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retreat inland which is kind of a

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feedback that will maintain that which

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that retreat and that feeling and that

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acceleration for many years to come

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we've been looking at 40 years of

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changes in velocity over that whole

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sector and what we see is a continuous

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increase in discharge of ice from the

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glacier to the ocean in most cases when

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you look at ice sheets the important

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stuff is taking place at the bottom that

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you can't see

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so the grounding line is the place where

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the glacier detaches from the bed and

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becomes a float with the ocean and as it

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becomes a float in the ocean we see the

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retreat of the grounding line on the

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glacier as it's being melted more

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strongly by the ocean and you see that

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the bed of the glacier slopes inland it

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never gets away from the water the water

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keeps following the glacier because it

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gets deeper inland the first time we

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could image it was in 1992 and in 2011

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we look at the data and went wow it's

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been so much change in the position of

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this grounding line you can't miss it

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so this bunch of feedbacks that makes

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this this retreat and stoppable

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unless suddenly the glacier starts

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retreating in a bed that rises up right

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but we don't see that in any of these

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glaciers this system is evolving very

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fast and is progressing exactly as you

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would you expect if it was about to

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collapse

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they retreating at rates of about a

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kilometer per year if these glaciers

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were sustaining this rate of between