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Antarctic Ice Cap Breaking Up?
vrmlguy writes "Here's another reason why I'm glad to live well away from any of the coasts, East, Left, or Gulf: The Antarctic icecap (and a large number of Northern Hemisphere glaciers) may be melting faster than previously suspected. New Orleans, which is already 8 feet below sea level, may be just a memory in less than a century." Interesting stuff.
The tone of comments here seems to me to reflect a real head-in-the-sand attitude... if the release of chunks of ice the size of a small state is no big deal, what WILL get your attention? So what if this has been going on for 14,000 years - it's clearly speeded up tremendously in the last ten or so. And sure, we can put up a big dike to save Manhattan, but what about the 10 million people who live in other parts of the NYC metro area? Not to mention the other 50-100 million Americans living in coastal areas.
To give a specific example, I live in eastern Long Island, where a huge fuss is made about protecting our "sole source aquifer" from pollutants. What's the biggest threat to the aquifer? Salt water encroachment - and the extent of that is determined by the effective "height above sea level" of the water pressure. Currently the highest pressure points are 50 feet above sea level - but huge areas of the aquifer are only at pressures a few feet above sea level, so a sea level rise of even 3 feet would tremendously reduce the quantity of fresh water available here.
Multiply that problem by thousands of local regions with similar issues, and you're talking some serious costs that go with even a small sea level rise. This is a big deal folks!
Energy: time to change the picture.
New Orleans has more problems than sea level rise.
The article mentions that the barrier islands and wetlands around the mouth of the Mississippi are shrinking. This is largely due to the flood control and silt control on the Mississippi River. The dams and levees that keep the river navigable and that protect all those farms along the river also prevent the natural transport of sediment to the sea. This means that while the weight of the delta continues to cause it to sink, there is not as much sand to keep building new land.
The Army Corps of Engineers, which has been trying to tame the Mississippi for decades, may in the end be responsible for the first abandonment of a major city in the modern era.
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Don't be so hasty and naive. Think for a moment. If the Earth is warming what then should happen ? Increased heating should produce more active air mass transport to the poles. At the poles this will increase snowfall since it will be bringing in humid air. It should also produce stronger colder winds from the poles as the global heat engine starts to more effectively move heat from source to sinks.
... yeah so, thats no news, but the actual measurements are accurate.
Eventually, however the transported heat will lower the overall temperature far enough that the ice will start to melt. By then of course it is too late. I think its too late now. There is nothing we can do, there is probably nothing we could have done. It was inevitable.
There is abundant evidence for global warming. If you go looking for it you'll be amazed.
As for the opposite view, what are the options:
* GCMs arent accurate
* the old satellite argument. Now didn't I read that the recalculation of the satellite orbits showed that the orbital decay masked the increasing temperature ?
Can't think of any more. Apart from the personal slander I've heard.
On the opposing side what evidence is there for warming:
* the thermal pulse propagating down through the perma frost.
* increased wind and wave action over the last 40 years.
* ice thickness reduction in the Arctic and Antarctic.
* coral bleaching
* oxygen isotope measurements of the last 10,000 years.
etc...
But since this seems to be a religious / ideological view with many of the proponents I have absolutely no expectation that they will change their minds. If they are genuinely interested in the truth I would only suggest they look at the evidence and distrust anything that feels 'comfortable'.
Peter
Bitter and proud of it.
The real problem with melting ice caps is not the immediate sea level rise, but rather a break in the formation of North Atlantic Deep Water (NADW). NADW is the driving force behind the worlds largest ocean currents. In the north atlantic, extremely salty, cold water descends to the bottom of the; this downward flow, draws water behind it, initiating global thermohaline circulation. This circulation acts as a belt that rotates around the world, Americans would most likely identify the Gulf Stream lying off the coast of the Eastern United States; this stream is caused by the sinking of the NADW; however this flow of water from the equatorial regions of the atlantic most notably affects England and North-Western Europe. If the Polar ice caps continue to melt, or a fresh water lake in the cap were to rupture and spill out over the North Atlantic, the salty/cold water would be dilluted and would no longer sink to the bottom. This would cause all of the major ocean currents to slow and ultimately cease. Most likely the first place that this effect would be seen is in dramatic weather change in the Northeast Atlantic, if the Gulf stream stops then warm water will no longer carry warm water to these upper latitudes, resulting in much colder temperatures, and possibly a regrowth of some ice sheets over regions of England and Northern Europe.
-OctaneZ
I also think the media's attempts to hype up global warming are regrettable. Flimsy alarmism gives the impression that global warming is not a real problem, which I think it is. Air-conditioned corporate cubicle life can probably be totally insulated from the effects of global warming for the forseeable future. The difficulties are elsewhere:
that most of the Netherlands and other countries have significant ocean-side property that should be flooded, because it's below sea-level. Isn't it amazing what a little bit of old technology, called a WALL can do to a potentially flooded city in this situation?
Darn media blitz of bad news with no thought behind it...
Rise in sea level has little to do with salt encroachment. I lived on an island for a while and I learned about a freshwater lens. This is where fresh rainwater falling on the land flushes out saltwater so shallow groundwater is fresh and deep water is salt. A rise in the sea level just raises the height of the fresh water. Serious encroachment occurs when rainwater is kept out of the ground (storm sewers) and the fresh water is removed from the lens by pumping from wells. The missing normal flow of freshwater is replaced by outside water from the ocean which happens to be salty. At the end of a long dry season (in the tropics) my well did start to smell.
The truth shall set you free!