Faithful reader Bob W writes: "I'm a little curious about what archaeology has to say about global warming. I read that the reason that Beringia is no longer above sea level had to do with global warming. Now the scientists are telling us that the sea level will rise with global warming. It rose then, and now you're saying it will rise again? How is that possible? Which of these statements is true?"
Ilulissat Iceberg, Greenland. Photo by kaet44
Both are true, Bob, and oddly enough, for the same reason. The sea level rose at the end of the Pleistocene because glaciers covering all of Canada and parts of North America (not to mention Europe and Asia) melted, a direct result of the global increase in temperature. All that water had to go somewhere: our atmosphere can only absorb so much water. Scientists believe that as the icecaps shrink and the glaciers in Greenland and elsewhere melt, the sea levels will rise again.
Comments
Even if the ice caps do not loose ice the sea level will still rise a bit with global warming. This is because of thermal expansion of the sea water. The ocean has huge thermal inertia so it takes hundreds of years to come into balance with the atmosphere and thus the rise takes that long to complete. Sea level rise from ice cap loss could be a lot faster.
What does archaeology say about anthropocentric global warming?
Ancient societies have been affected by climatic events and changes, but these are not anthropogenic changes.
Some have linked some post last ice peak event climate changes to the rise of agriculture – but the jury is still out on that.
What archaeology teaches us (or would if we paid any attention at all) is that when climate change happens, regardless of who or what is to blame, it has huge impacts on society. Many many cultures have ended by ignoring climate change—or rather by not having the tools or the breadth of knowledge and experience to adapt when it came. Modern societies do have the tools and knowledge and experience to work out a strategy to deal with the possible changes and ameliorate some of the worst aspects—some just aren’t willing to spend the money or deny the reality.
Kris
…maybe we should start building an ark.
;o)
lots of arks & big scoop shovels
The value of my home will increase as I will have ocean front property!
For anyone interested in this topic, I highly recommend a new book edited by by Brian Fagan titled The Complete Ice Age: How Climate Change Shaped the World. Essays by Fagan and others explain the dynamics of of glaciers, climate change, and human responses in a better way than I have ever encountered. The book is a bit pricey ($40) but is loaded with fantastic illustrations. I would try to get it used on Amazon.com or some other place.
The phrase “climate change” has become synonymous in popular usage with suspected warming due to human generated CO2 and other gasses which are involved in heat transport, though an objective look at the last ten thousand years show plenty of climate change having happened, some of it quite rapidly, and were our numbers as great as they are these days, these changes in climate would be equally calamitous as any being predicted now. Interetingly, climate change can be caused by humans even without buring petro-carbon. Take, for instance, the case of Kilimonjaro’s dissappearing glacier, and presumably others such as some in the the Andes, which used to recieve significant moisture due to the forests whose evapo-transporation/respiration produced and lofted into the region’s atmoshpere enormous volumes of water, and which, due to land use changes (deforestation and grazing) in the region from which the prevailing winds come, that moisture is reduced. Even without warming there could very well be disappearing glaciers. Glaciers can extend even in the warmer sub-tropics, such as seen at the terminus New Zealand’s Fox and Franz Josef Glaciers on the South Island, if there is enough snow to replenish them. One salient fact of our natural history over the last 20 thousand years is that as the temps warmed, conditions favorable to human activities in agriculture and civilization improved steadily, including increased precipitation, longer growing seasons and favorable climate while periods of cooling accompanied a general drying out of the environment and expansion of inhospitable and arid regions.
Shishmaref, as well as other Bering Strait villages are currently experiencing massive erosion along the beaches and some are in the process or planning for whole village relocation. Others are in the process of planning and completing erosion control devices.
Some of these village sites have been occupied over the last several thousand years, or longer, without the threat of erosion at the current levels.
The communities are working hard to preserve their cultures despite the changes in conditions. Only time will tell .
Before the Little Ice Age that started around the beginning of the 14th century, most of Greenland was free of ice, in the summer. And even now with all the global warming land on Greenland that was farmed by the Vikings is still under ice.
To find out how high sea levels will rise if Greenland’s glaciers melt just look at what the sea levels were before the 14th century. There are plenty of buildings and other construction from that time still standing in Europe. Just look at where the water level was then.
I don’t think things will get as bad as all the doomsayers predict. If your paycheck is from forecasting doom, you forecast doom, big time!
Bering Strait is a literal choke point for climate change, with regard to ice floes and current flows. Did you all see the National Science Foundation release on the stuff last year? I blogged it here.
Ken, You need to do a little research. The Greenland ice sheet has been in existence for at least 100,000 years, and more likely 400,000 to 900,000 years.
I also wish people would quit insulting climate scientists with this crap about forecasting doom to increase their funding. The climate scientists I know are dedicated professionals who are desperately trying to provide us with accurate information so we can understand what is happening and what we need to do.
Who gets paid for forecasting doom? No one.
Who gets paid to cover up such forecasts, to continue profligate living until the end?
The grasshoppers never learn from the ants. Never.