William sent in this link – https://www.nationalgeographic.com/science/article/430000-years-ago-a-me… … 430,000 years ago, a meteor exploded over Antarctica and left behind a debris field that has recently been explored by scientists. It was of course a patch of ground, without ice, that is thought to have lain dormant during the whole of that time, during Ice Ages and Interglacials. At 430,000 years ago we have the Neanderthals and other early humans, but not living in the vicinity of Antarctica. National Geographic describe it as an atmospheric blast that produced a flaming incandescent trail in its wake. It didn't leave behind a crater as it exploded in the air – above the surface of the ground. It did, however, leave behind its fingerprints.
430,000 years ago is around the time of the Anglian Glaciation in Britain, known mainly from East Anglia but reckoned to have reached further south than any earlier Ice Age. According to Wiki it began 480.000 years ago and came to an end at 424,000 years ago. It is assumed ice sheets around the world grew exponentially at the same time. According to the Wiki it corresponds to Pre-Illonian B in North America – but the extent of the ice sheet, westwards across North America, might be interesting to have a peak at. One has to take into consideration that it is assumed the Anglian Ice Age covered a wider area of the earth then as water was locked up as ice. What if the poles were positioned slightly differently? Would that mean Antarctica was not the frozen world of today?
At https://wattsupwiththat.com/2021/06/16/icebergs-drifting-from-canada-to-… … concerns a new study which has looked at sea floor bathymetry, using sonar. This has shown up huge grooves at the bottom of the Atlantic as icebergs ploughed the bottom of the ocean. They date, it would seem, to the last Ice Age, and are associated with Heinrich events. The peculiarity is that icebergs were able to reach as far south as Florida without melting [or not to any great degree]. The authors say this fact is amazing. However, one might say not as amazing if there had been a different configuration of the poles – particularly during the Late Glacial Maximum. If one assumed the poles do not move and then it is an amazing discovery. To try and understand how it might have happened modelling was used. Some of ther results are interesting – and the links provided.