Alaska ice free 17,000 years ago

3 Dec 2012

This story has a direct correlation with the previous one as it provides the means for human migration into North America quite a bit earlier than previously allowed. This has been forced on science as there is no doubt now that humans were living in Chile and Peru as early as 1450 years ago, whereas the old consensus, Clovis First, insisted humans could not have entered the continent that early. The story can be seen at www.sci-news.com/othersciences/paleoclimatology/article00432.html ... and began as a way to measure salmon runs in western Alaska in the past and compare them with today's numbers running during spawning season. The research was centred on Sanak Island, part of the long spine of a peninsular that arcs across the Bering Strait towards the Aleutians, and homed in on a lake. The lake, the sediment core and C14 methodology showed, was a waterscape as early as 17,000 years ago - which came as a surprise. It is assumed by the researchers, and everybody concerned, that Alaska was frozen during the Late Glacial Maximum, and glaciers existed where the lake was born. No earlier dates were achieved which indicates the lake itself came into existence at that time - but this does not necessary imply it appeared as a result of the melting ice sheet. On the other hand, the spine of the peninsular was probably a range of mountains during the last Ice Age, and as the Bering Strait was submerged the mountains were too high to disappear, remaining as a sliver of land surrounded by lots of islands. On that basis the mountains may well have been glaciated - but it is worth pointing out that this may not strictly be true, especially if a large part of Alaska was not frozen during the Late Glacial Maximum.

Meanwhile, at www.sci-news.com/archaeology/article00755.html ... the subject is an engraved stone as reported in the journal Chinese Science Bulletin and reputedly goes back to 30,000 years ago - the beginnings of the Late Glacial Maximum. This was the deep into the Palaeolithic era and the stone was presumably engraved by hunter-gatherers - but why? This find is going to spark a lot more investigation by the Chinese of their deep past and we must all be interested in what was happening in that part of Asia during the next 10,000 plus years or so. Was there ice in Siberia and Alaska, and if not, what were the average temperatures? Was it temperate and was the Late Glacial Maximum a fact only in NW Europe and NE America (as claimed by Peter Warlow, for example, at our last Cambridge Conference, a few years ago). Interesting days and largely outside the control of western academics.