Yedoma

At https://en.wikipedia.org/wiki/Yedoma … Yedoma are Pleistocene age permafrost pockets with ice content at 50 to 90 per cent by volume. Yedoma are abundant in eastern Siberia, such as northern Yakutia. They also occur in Alaska and the Yukon. In many regions this permafrost is many metres deep. Not only that, Yedoma occur from western Siberia right across the top of the world in Alaska and Yukon. These are areas thought to have been ice free in the Late Glacial Maximum. A more infromative source is https://www.sciencedirect.com/science/article/abs/pii/S0277379108001054 … which concerns permafrost deposits on an island in the Lena delta, NE Siberia. It focuses on the period, 50,000 to 32,000 years ago, embracing the Laschamp Event and the beginning of the Late Glacial Maximum. However, one of the more illuminating articles is in Quaternary International 89 [2002] pages 97-118 ‘Permafrost deposits in the Arctic region of modern Siberia’ which says the Late Glacial Maximum was basically warmer in Siberia than it is in the modern world.