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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.
Louisiana has an perplexing predicament. It looses millions of acres of coastline every year to the Gulf of Mexico. The Port of Baton Rouge is the second largest deep-water port in the United States, as far as dollar amounts. The Mississippi river is being diverted from its natural course (actually, the course nature wants it to take). It will take billions of dollars to keep the Mississippi on it's course and not flooding. But, it is the flooding of the Mississippi that would keep the state from loosing as much coastline. New Orleans has another problem--it is sinking under its own weight. All of the Slit from the Mississippi is being thrown off of the continental shelf and into the depths of the gulf. Eventually, and this will wreak havoc on Louisiana, as well as the entire Mississippi delta, the Army Corps of Engineers will have to let the Mississippi follow the straight path to the Gulf now known as the Atchafalaya River. This will flood many towns and small cities and will leave New Orleans and Baton Rouge without a city--and without a port. The Atchafalaya is a treacherous river, and will be even more treacherous if it has that much more water going down it. It will probably destroy highways that cross it (Interstate 10) and levees around it. It will probably be impassable to boat travel for months if not years. Whoever is the politician that deems it's time to do this will probably be very unpopular. It would be interesting to know how this will play out. (BTW, Baton Rouge is 20 feet above sea level, and it's over 100 miles from the coase. Imagine what rising sea levels will do to this state.)
Much of the initial salt water encroachment was caused when oil companies dug canals from the gulf and through the swamps (it's not just oil companies, but that was one major problem). The amount of change of salt in the water caused the vegetation to die, and the coastline to erode (with the help of Nutria rats, which were introduced to eat another type of vegetation...I digress).
The problem with New Orleans is that once the coast is gone, waves will be beating on its levees. At that point, you better have some kick-ass levees or just leave.
I guess what I mean to say, is that the salt water encroachment is a problem with above surface water, not ground water, in Louisiana. It gets to the plants through natural erosion of the coast line.
This past summer, which was the second year of a bad drought here, rice farmers were pulling salt water from their wells. I assume that is what you are referring to.
Excuse me, I am talking about another thread. I'm just lost today. Ignore that last comment.
Better patent it before anybody else starts using my business model.
Bugrit! Millenium hand and shrimp!
Who the hell thought they were all smart when they wrote that article? They are right that the oceans are warming, but claiming the changes in the ross ice shelf is evidence for thier case is crazy. Their dates are between december and march, crossing over 10 years. We know that the ice formation in antartica changes from one year to the next, there might be a visible change between two seperate years, but the third year it could match or exceed both prior. According to a poster I have the antartic ice was its largest in recorded history in 1988. Or at least as long as it has been monitored. So, what's the big deal.
Spring is here. Don't believe me, look outside!
Netherlands 300 years ago used and developed this technology. They called it a dyke. No, you perverts, not a lesbian.
Spring is here. Don't believe me, look outside!
Maybe they should get some MicroFans
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.
if ($it != $onething) {$it = $another;}
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!