Monday, February 19, 2007
Remember that really bad Kevin Costner film, “Waterworld”?
It seems our near future (i.e., 100 to 200 years) might include some of the basis for that film, hopefully without the bad acting. This from the Guardian, via HuffingtonPost:
New studies of Greenland and Antarctica have forced a UN expert panel to conclude there is a 50% chance that widespread ice sheet loss "may no longer be avoided" because of greenhouse gases in the atmosphere.
Such melting would raise sea levels by four to six metres, the scientists say. It would cause "major changes in coastline and inundation of low-lying areas" and require "costly and challenging" efforts to move millions of people and infrastructure from vulnerable areas. The previous official line, issued in 2001, was that the chance of such an event was "not well known, but probably very low".
The melting process could take centuries, but increased warming caused by a failure to cut emissions would accelerate the ice sheets' demise, and give nations less time to adapt to the consequences. Areas such as the Maldives would be swamped and low-lying countries such as the Netherlands and Bangladesh, as well as coastal cities including London, New York and Tokyo, would face critical flooding.
The warning appears in a report from the Intergovernmental Panel on Climate Change, which assesses the likely impacts of global warming and will be published in April. A final draft of the report's summary-for-policymakers chapter, obtained by the Guardian, says: "Very large sea level rises that would result from widespread deglaciation of Greenland and West Antarctic ice sheets imply major changes in coastlines and inundation of low-lying areas, with greatest effects in river deltas.
"Relocating populations, economic activity and infrastructure would be costly and challenging. There is medium confidence that both ice sheets would be committed to partial deglaciation for a global average temperature increase greater than 1-2C, causing sea level rise of 4-6m over centuries to millennia." Medium confidence means about a five in 10 chance.
What’s really scary about this prediction is that the influx of so much freshwater would likely interrupt the oceans currents. Fresh water and salt water do not readily mix, and therefore the fresh water would set up a boundary between the two. The normal circular current rotations where the warmer salt water rises, moves around, cools and then sinks would not work anymore. If this were to happen, we could be seeing much larger climatic changes than just rising sea levels and inundated coastal cities. (Which, incidently, was the subject of another forgettable Hollywood film, "The Day After Tomorrow". Those whacky, reactionary Hollywood types, always making goofy movies out of probable events.)
Personally, I had been hoping that the human race would run out of cheap energy before we inflicted huge damage on our home planet of Earth. However, that seems to be no longer the case. It appears as if these two things are going to occur simultaneously. I predict it will not be pretty. Our food production and distribution system will likely fall apart right at the time that massive population relocation is going to have to occur. Very selfishly, I guess I am glad that I will not likely be around to see the worst of it. Our children’s children may have a very hard time of it, though. I certainly hope I am wrong, but I cannot see another conclusion that is more logical.
What the world needs right now is for a “Manhattan-type project” on a global scale to find ways of immediately reducing our greenhouse gas output, finding new energy sources that will replace all petroleum and coal based sources, and figure out a way to cope with the likely changes that will result in the next 100 years. However, I have absolutely no hope that this will ever happen. Our society is pretty good at coping, but only AFTER a disaster has happened. We do not seem to be able to deal with things proactively, even when our very existence, as we now know it, may be at stake.