This is an interesting image from the Aberystwyth team which has been modelling the behaviour of the BIIS (British and Irish Ice Stream) during the Late Devensian glaciation. It appeared on one of their recent publicity pages. I'm not sure how old the image is -- the modelled animations are a bit difficult to get at with old Apple Mac computers.
But this is a reconstruction of the situation at 21,000 BP, following two or three thousand years of retreat from the maximum ice edge position, which was near the shelf edge at the bottom left of the image. If you look carefully, you can see Devon, Cornwall and the Isles of Scilly.
This image may come from one of the computer runs made by the Aberystwyth team a few years ago, showing the "maximum" ice cover consistent with evidence on the ground (and on the sea floor). But it is faithful to the laws of physics and conforms with what we know about glacier and ice stream behaviour. What is important is that it confirms that the idea of a narrow ice lobe pushing through St George's Channel and extending all the way to the shelf edge is more than a little ludicrous -- because, as I have pointed out many times on this blog, ice does not push out in long lobes in unconstrained locations such as the Celtic Sea arena -- and it MUST have spread laterally onto and possibly beyond the coasts of Devon and Cornwall.
And what is even more interesting -- and surprising -- is that DEVENSIAN Irish Sea ice is shown flowing across Somerset and all the way to Salisbury Plain. ( I had assumed something like this for the Anglian Glaciation, but not for the Devensian.......)
We know from James Scourse that new modelling is under way, which will take account of the latest field research by the BRITICE team. Watch this space......
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