That piedmont glacier........

On doing some more research on ice directions etc at the peak of the Devensian (ie at the time of the LGM) I came across this map in Greenwood and Clark 2009 -- after McCabe 2008.  Interesting -- because it shows ice streaming off the south coast of Ireland, derived from the Irish Midlands.  The portrayal of the Irish Sea ice stream is speculative, and of course there is no ground evidence south of the Wicklows to support it.  (If there is evidence for this phase of activity involving the Irish Sea ice stream around 22,000 years ago, it is on the bed of St George's Channel, and is thus a bit difficult to get at.....)

If we wipe off the Irish Sea ice stream arrow from this map, and assume that the Southern Irish piedmont glacier went into a phase of rapid expansion or surging behaviour, at the same time as a reduction in the power of ice flowing through St George's Channel from the north, we have the scenario on which I speculated a few days ago.