According to William Ryan and Walter Pitman in their book Noah's Flood: The New Scientific Discoveries About the Event that Changed History (1999), the Black Sea was once a freshwater lake that suddenly and violently filled up with salt water from the neighbouring Mediterranean Sea sometime around 5600 BCE, causing the lake to drastically rise and turn into a connected "sea". He adds that all the flood stories of the Near East are somehow a memory of this major event in prehistory. My immediate impression is: "Yeah, right. Tell me another story".
This is a good article from Flavin's Corner entitled Atlantis in the Black Sea? which nicely expresses the kinds of criticisms I also have in mind:
"Okay, so the Black Sea flooded c. 5200 BCE and maybe some people drowned. Maybe… Why not associate this with Atlantis? Why bring in biblical myths? Are we bored with Plato? Whatever the answers to these silly questions, I'm profoundly disappointed with National Geographic and what I regard as a cheap attempt to entice Christians to open their wallets."As someone who grew up in a hardcore Christian household with biblical literalism crammed down my throat, I'm thankful that school "corrupted" me into learning about evolution and science. So while some may feel sensitive to this Christian pandering, you can probably imagine my particularly personal perspectives on what I see as nothing less than religious stupidity and lies. Even worse, a mockery of spirituality by dunces hiding behind one religion or the next who aren't intellectually sophisticated enough to make a distinction between metaphysical questions about existence on the one hand and the physical reality immediately around us on the other hand that can only be understood through the method of science and logic.
In case anyone is still confused, Noah and much of the biblical myth of the flood in the book of Genesis is based on established Babylonian legends beforehand that had also been recorded. It's also not necessary for a people to have a real flood in order to invent a legend about a mythical flood. My own impression of this particular flood myth of the Near East is that it is in fact originating from a creation tale started by coastal peoples who would have looked out into the sea (whether the Black or Mediterranean Sea) with contemplative mind and pondered that maybe it was the sea that came first, the land emerging later from it. This is the basis of Egyptian creation myth, for example, where Nu "the Nile god", the primordial waters incarnate, is the oldest of gods and creator of all. Flood myths are common around the world, even among the Maya, and there is no need nor is there any evidence for a real world flood to inspire ancient people to recount a flood myth (as if this even needs to be said in the company of educated adults). Abstract association, something that humans do well, suffices to explain these legends.
Yet, even though I smell a scam to sell a truckload of books in the name of sensationalism, what exactly did happen with the sea levels of the Black Sea? Where's the real information? Now that the internet and popular "science" magazines are swamped with headlines about Noah's Flood, it's hard to get at the more "mundane" truth that unfortunately can't match the rabid publicity of a good mythological tale. Part of the problem too is that the more level-headed researchers are not connecting with the people and sharing their information in a public-friendly format in order to properly educate everyone. So, in effect, universities and other institutions are only encouraging more sensationalism as their scientists and researchers continue to shun the public eye, detaching from the world that funds their science.
There's a book by Valentina Yanko-Hombach that I need to get my hands on called The Black Sea Flood Question: Changes in Coastline, Climate and Human (2006) that apparently criticizes Ryan and Pitman's "sudden flood" hypothesis. Interestingly, she lives in my city, Winnipeg! I could walk over and touch her, but I'm sure the security guards would unleash their hounds on me so I better not. If only Yanko-Hombach were more hip and net-savvy by taking advantage of the word-of-mouth of the internet, her message could finally be heard over the din of nauseating sensationalism. Instead (and I believe this a perfect example of what's going wrong with modern academia), she hides her views behind expensive technical books and outdated copyrights. So not a peep is heard from her data unless one can obtain access to her work, either by shelling out the money or accessing it in a well-stocked university library, and unless one has a strong archaeological background to understand it. It's a hideous shame.
It's even more shameful because there is truly a segment of the public that's had enough of sensationalist, dumbed-down lies and wants plausible explanations with real science and responsible journalism behind it. You can see this seething undercurrent of anti-populist dissent in the discussion that took place on groupsrv in December of 2006 concerning the dubious evidence for "Noah's Flood": http://www.groupsrv.com/science/about189563.html.
As of now, I still don't have a clue about what happened to the Black Sea shoreline at that period. Bare with me. I will certainly have to dig for Yanko-Hombach's work underneath the flood of pop-science because of course, it's one crucial detail in understanding IE/Pre-IE speaking peoples who lived in that area at the time.
 Andrews, Dictionary of Nature Myths: Legends of the Earth, Sea, and Sky (2000), p.153 (see link).