At https://archaeologynewsnetwork.blogspot.com/2020/02/long-ago-record-of-b… …. the problem is the mainstream theory to account for sudden drops or rises in sea historical sea levels. For instance, continental shelf systems, including the one beneath the Bering Sea (see image below), was dry land during the Late Glacial Maximum. We don't have much information or research on what the situation was like prior to the LGM (prior to 30,000 years ago) but it is clear that it was dry land during the LGM as mainstream theory is that Beringia (as it is now known) harboured humans on their way from Siberia to N America (who arrived in the period between the end of LGM and the onset of the Younger Dryas cooling period. Mainstream theory is simply that during the Ice Ages lots of water is locked up in a massive ice sheet stretching across the top of the world (the northern hemisphere). Hence, after LGM came to an end ice melt (as it grew warmer, fairly abruptly) caused sea levels to rise and drown Beringia – but here is the rub as outlined in an article in Scientific Advances …
…. some researchers say the presence of Pacific species in the Arctic Ocean implies the Bering Strait was open water by 13,000 years ago. This is roughly the date when the Younger Dryas cooling period kicked in – and the period between the end of LGM (roughly 15,000 years ago, and the onset of the YD, was warm – and one would have thought the ice sheets would have melted. They had enough time. If, as seems likely, the shift from cold to warm was fairly rapid. Richard Alley, in his book 'The Two Mile Time Machine', a reference to an ice core from Greenland, claimed temperatures rose by 10 degrees within 50 years (and possibly in a shorter period of time). That is virtually instantly – as much as geologists can measure. It was even used by climate alarmists to heighten fear mongering over global warming – coming on rapidly. What the trigger to the sudden rise in temperature was is more or less an unknown. Lots of guess work – and hype to accentuate the rapidlity (and we all should be worried as the end of the world approaches). Naturally, this research paper pays lip service at least to the climate change meme but it is interesting to note how they get around a problem – why did sea levels rise during the cooling period of the Younger Dryas. Firstly, they have to suppose the ice sheets still existed (in spite of 2000 years of warming). Sediment cores in Beringia seem to show dry land still in existence in 11,500 years ago (roughly at the end of the Younger Dryas and the beginning of the Holocen (when temperatures again increased on a global basis). Funnily enough they may not have increased to any degree in Beringia as during the LGM this region was not glaciated (as numerous studies have shown). Indeed, NE Siberia and lowland Alaska and the Yukon were not glaciated, either. The authors have a problem as they need ice to cause sea levels to drown Beringia but there was none in proximity during LGM. There is nowadays and the climate today is much colder than it was during LGM – which is itself something of a paradox. They are forced to assume massive ice sheets existed across most of North America (in what is now Canada in the main) and this was still in the process of melting (even though catastrophic flows of water from melting ice had been a feature prior to the Younger Dryas). The study authors seem to have done an exercise in mental gymastics to reach their conclusions. They accept there must have been a sea level fall, or at least a standstill, during the Younger Dryas cooling period. How then did a melting ice sheet lead to sea level falling. The answer is gravity we are told. It was the melting ice that caused the cooling event. This is an appropriation of the old missive that a huge sink of cold water flowed into the Atlantic (somewhere) and switch on the cooling period – usually defined as a massive catch of glacial water land locked that was suddenly released and poured into the ocean. However, no evidence of where this glacial lake was situated or how it travelled through the landscape in eastern N America has ever been found, leading to the idea it flowed north along what is now the MacKenzie river system into the Arctic (and therefore by a northern route into the Atlantic). We do know lots of water went west through the Scablands but this idea has been neutered and is now considered a series of small events rather than a single mass event. This has the additional benefit of erupting into the Pacific not too distant from Beringia. Might this theory be revived – now that Bretz has died. However, it is the Atlantic where they want the cold pulse of water to strike – affecting the ocean conveyor system (shutting down the AMO). I suppose it could be argued this is a good try in order to explain the problem – a lowering sea levels during a cooling period. The article is available to read at https://doi.org/10.1126/sciadv.aay2935
In a catastrophist model one might look at all these changes in sea level as abrupt affairs rather than tediously slow exponential rises (which came about by drawing a line between two points and assuming sea levels rose gradually between those two points). In other words, changes in the geoid could amply explain the mystery. One might go further in a catastrophist model and broach the idea of pole change at the end of the LGM and a wobble in order to explain some oddities of the Younger Dryas period. All the old calculations regarding how difficult it would be to cause the poles to move are out of date since the discovery of plasma and electro magnetic effects at the poles, and the possibility of a Centaur object floating around in the inner solar system. Mind you, we may have to wait until the next Centaur object escapes from Jupiter in order to find out what possibilities there might be. Trying to make sense of a problem such as outlined in this paper is restricted by what is allowed by mainstream. Pity.