During the last interglacial, herewith dated 125,000 years ago average global temperatures, it is said, were not a lot different than today – yet large areas of what are now coastal zones, sometimes with great cities, are thought to have been under water – see http://phys.org/print339957733.html
Not a lot of research into actual regional sea levels have taken place – most of what is bandied about is modelled data and not actual field research. However, it is quite clear that sea levels in the last interglacial, and at various other times, differed to those of today. It is assumed they rose universally in every part of the world, an assumption that is carried into the models. The reason why is derived again from an assumption – that ice melt from the Ice Age event prior to the interglacial was enough to account for the sea level changes where it has been documented in the real world.
On the Indian Ocean islands of the Seychelles the sea level was between 20 and 30 feet above modern mean level during the last interglacial – and fossil corals from the period are being used to increase global warming doomsaying. The implication that is being foisted on the general public is that a small increase in global temperatures is potentially a threat to life as we know it – and not only that, even the Antarctic and Greenland ice sheets are under threat. This is of course complete phooey. The problem is exacerbated by scientists favouring models over reality. In the real world there is no global warming – it has been static for at least ten years. Some say it has been at a plateau for 18 years – which would be an even worse scenario.
On the one hand we have geologists assuring us that the Antarctic ice sheet has been with us for millions of years, through episodes of greater warming than has occurred in the last 35 years. On the other hand we have a group of scientists spreading a nonsense that the polar ice sheets are about to melt – which contradicts geological history. It is all a matter of guesswork – or the pot of gold.