The extinction does not coincide with the end of the last ice age, but does coincide with a minor yet severe climatic reversal that lasted for about 1, 000 & ndash; 1, 250 years, the Younger Dryas ( GS1 Greenland Stadial 1 ), characterized by glacial readvances and severe cooling globally, a brief interlude in the continuing warming subsequent to the termination of the last major ice age ( GS2 ), thought to have been due to a shutdown of the thermohaline circulation in the ocean due to huge influxes of cold fresh water from the preceding sustained glacial melting during the warmer Interstadial ( GI1 Greenland Interstadial 1 : ca . 16, 000 11, 450 14 C years B . P . ).
42.
The climatic deterioration which culminated in the Last Glacial Maximum, between about 26, 500 and 19, 000 20, 000 years ago, drove humans out of Britain, and there is no evidence of occupation for around 18, 000 years after c . 33, 000 years BP . Sites such as Cathole Cave in Swansea County dated at 14, 500BP, Creswell Crags in Nottinghamshire at 12, 800BP and Gough's Cave in Somerset 12, 000 years BP, provide evidence suggesting that humans returned to Britain towards the end of this ice age during a warm period from 14, 700 to 12, 900 years BP ago ( the B�lling-Aller�d interstadial known as the " Windermere Interstadial " in Britain ), although further extremes of cold right before the final thaw may have caused them to leave again and then return repeatedly.
43.
The climatic deterioration which culminated in the Last Glacial Maximum, between about 26, 500 and 19, 000 20, 000 years ago, drove humans out of Britain, and there is no evidence of occupation for around 18, 000 years after c . 33, 000 years BP . Sites such as Cathole Cave in Swansea County dated at 14, 500BP, Creswell Crags in Nottinghamshire at 12, 800BP and Gough's Cave in Somerset 12, 000 years BP, provide evidence suggesting that humans returned to Britain towards the end of this ice age during a warm period from 14, 700 to 12, 900 years BP ago ( the B�lling-Aller�d interstadial known as the " Windermere Interstadial " in Britain ), although further extremes of cold right before the final thaw may have caused them to leave again and then return repeatedly.
