posted
Interestingly, CNN.com's cover story on GlobalWarming spent the shortest time ever on their front page : replaced by the ever oh so important FinalFour of college basketball. CNN.com also removed their link to an interactive page showing the sealevel created by the predicted global temperatures of 2100 : ie the eventual sea level expectable from ~125,000years ago during the LIG (LastInterGlacial) period when global temperatures were last comparable to that expected in 2100. Fortunately, the links I saved are still working. Of course there is expected to be some lag time in sealevel rise due to how quickly the temperatures are rising now compared to during the LIG, but then the current glacier/icecap/permafrost melting is proceeding MUCH more rapidly than was predicted.
This thread was originally titled Houston/Galveston and PortArthur : WorstCaseScenario inregard to hurricane storm surge. And the simulations are still useful pictures of cities being drowned in the ocean. Six animations of the flooding from a 5.7metre/19foot storm surge put together by Dr. Gordon Wells of Mid-American Geospatial Information Center, Center for Space Research, University of Texas.
After first play of each scene, right-click on the round button then drag to control video speed, forward or backward.
posted
I think I can just about pick out the house I lived in during the four years I went to school in Galveston. I was near the UTMB complex, animation 4 and 5.
I loved that town.
Posts: 1014 | Registered: Jul 2005
| IP: Logged |
posted
Comparison maps will be added to show which cities/etc will be flooded. Meanwhile, check out the links in the first post.
Posts: 8501 | Registered: Jul 2001
| IP: Logged |
posted
As I said before: If Greenland and Antarctica melt, the ocean rises between 66to72metres/220to240feet: the minimum-to-maximum rise based on the volume of water contained in above-sealevel ice supported by land.
However, the icecaps' weight presses Antarctica downward into the Earth -- much like loading a boat will cause the boat to float lower in the water -- about 1kilometre/0.62mile. And just as a boat will float higher when its cargo is removed, the Antarctic continent will rise due to isostatic rebound as its icecap melts. Even taking into account the higher sealevel from icecap melting, land currently ~760metres/0.47miles under the ocean will rise above the new sealevel. So ice under the current sealevel which is currently grounded on the ocean floor will also raise the height of the new sealevel after the melting. Similarly Greenland; though to a lesser extent because its icecap isn't as thick, and a smaller percentage is being supported by the ocean floor.
Which means that a rise of 72metre/240feet is a more realistic minimum in the long run -- continental isostatic rebound occurs slowly after removal of the load -- when added to the heat-expansion of seawater's volume expectable with the rise in ocean temperatures which would accompany a total meltdown of the icecap.
Since LakeSt.Clair's surface is 175metres/570feet above sealevel, Detroit will remain above the ocean, as will everything along LakeErie's shoreline of 173metres above sealevel. Chicago's elevation is higher.
However, everyone living at LakeOntario's elevation of 73metres/243feet, or lower, might need houseboats. My bet would be that LakeOntario would become part of the AtlanticOcean in a total icecap meltdown.
Anyway, consult the NationalGeophysicalDataCenter's state elevation maps and GLOBEimages before building an ark .
Which apparently you replied to. So I'd guess you are asking about the effects of GlobalWarming expectable by 2100.
Michigan would face a LOT more mosquitoes for a LOT longer portion of the year. Possibly even carrying malaria and similarly-tropical diseases such as dengue. Other effects on Michigan and the GreatLake states will quite possibly be similar to that on NorthDakota GlacierNationalPark will be glacier free: most other glaciers in the contiguous states will have disappeared. The mountains' winter snow packs will melt much earlier and much faster; relinquishing the major part of their role in year-around water-management. Faster melting will lead to more spring flooding; and in turn, water rationing later in the year will become more the norm in the US.
Not that particular site. Elsewhere, it has been pointed out that WallStreet on Manhattan is less than 2metres/7feet above sealevel. Then there are predictions that hurricanes and their accompanying storm surges are due to strike the NorthEast soon.
posted
Out of curiosity, if the glaciers were to melt to the degree that they're currently projected to, what effect would that have on the salinity of the oceans? Would there be a perceptible impact, or would they (literally) just be a drop in the ocean? I mean, I know that it would have to be slight--the oceans are vast, after all--but I don't know what kind of tolerances various types of marine life have to decreased levels of salinity.
Posts: 16059 | Registered: Aug 2000
| IP: Logged |
I figure once we do away with winter in the continental US, THEN we can start worrying about restricting fossil-fuel vehicles.
Posts: 14554 | Registered: Dec 1999
| IP: Logged |
posted
Are these models based on static, fixed continental plates or do they allow for tectonic dynamics?
In other words I've always wondered what would happen to Greenland and Antarctica without all that heavy ice on top? I'd imagine that these landmasses would "float" at least a little bit higher on the mantle, and that the additional water elsewhere would weigh down ocean floors a tad. What's the net effect of these competing actions?
Posts: 105 | Registered: Oct 2005
| IP: Logged |
quote:Originally posted by aspectre: As I said before, "Since LakeSt.Clair's surface is 175metres/570feet above sealevel, Detroit will remain above the ocean, as will everything along LakeErie's shoreline of 173metres above sealevel. Chicago's elevation is higher" so Lake Superior, LakeMichigan, LakeHuron, and their bordering states will also remain above ocean level even in the worst case scenario for the future. However in the event of a total meltdown of the Antarctic and Greenland icecaps, I strongly suspect that LakeOntario and lower elevations would would become part of the Atlantic.
Which apparently you replied to. So I'd guess you are asking about the effects of GlobalWarming expectable by 2100.
Michigan would face a LOT more mosquitoes for a LOT longer portion of the year. Possibly even carrying malaria and similar tropical disease viruses such as dengue. Other effects on Michigan and the GreatLake states will quite possibly be similar to that on NorthDakota GlacierNationalPark will be glacier free: most other glaciers in the contiguous states will have disappeared. The mountains' winter snow packs will melt much earlier and much faster; relinquishing the major part of their role in year-around water-management. Faster melting will lead to more spring flooding; and in turn, water rationing later in the year will become more the norm in the US.
My bad, I forgot about that thread (give me a break, it was LAST May!).
Where is the influx of malaria and other disease going to come from? Malaria doesn't even really exist in Michigan right now so far as I know. Where does the wave of malaria carrying mosquitos come from?
Posts: 21898 | Registered: Nov 2004
| IP: Logged |
posted
In this day and age of near-instant global travel, it's quite possible for people to carry disease from continent to continent. If they quickly exhibit symptoms and are hospitalized, the spread of the disease can be stopped, but if someone contracts malaria in asia, flies back to Michigan, and is fed on by mosquitos soon after arrival, then it can start to spread, and before long will be endemic, and the only way to reverse it would be to kill off the entire population of mosquitos. Compare this to other diseases that have recently spread across continents, e.g. Avian Flu.
posted
Noemon, I read an article in March SciAm today about the oceans. It seems the real danger to them from human-generated change is the increase of acidity (actually reduction of slight alkalinity) from the increased CO2 dissolved into seawater. A whole lot of stuff might go extinct, stuff at the bottom of the food chain, which could have tremendous repercussions throughout the entire biosphere. This seems to be the fastest increase in acidity for the last hundred million years or so (I think they said), and they expect it will give ocean life very little time to adapt, causing severe disruption.
Posts: 6246 | Registered: Aug 2004
| IP: Logged |
posted
Tatiana, . Not even sure what to say, really. Take out that bottom layer of the oceanic food chain and the entire biosphere is pretty thoroughly broken.
Posts: 16059 | Registered: Aug 2000
| IP: Logged |
posted
Also, lake level rising could mean that relatively flat areas near the lake will become swamp rather than lake. Mosquitos need stagnant water to breed, so a rise in water level might not increase the size of the lake much (proportionally), but it might significantly increase the amount of stagnant water which becomes mosquito breeding ground.
However, I think that this is a fairly easy thing to fix. I believe that you can just drop some pumps in the swampy area and shoot water out across the water, disturbing the surface. This should make it impossible for the mosquitos to breed, and should be relatively cheap to implement, and not as harmful to the environment as other ways of cutting down the mosquito population (such as DDT).
posted
Actually, Lyrhawn, I originally thought your query was inregard to coastline flooding, and posted an answer to that question. Afterward I went back to reread the linked-to thread, noticed that you had responded there, then presumed that you were actually asking a different question. Deciding that others might be interested in the part already posted, I let it remain and edited in "Which apparently you replied to..." as explanation as to why I was continuing on to other effects of GlobalWarming upon your region.
As well as what Althai mentioned, malaria was once endemic in large portions east of the US ContinentalDivide: the eradication of which being the impetus for the founding of the Center for Disease Control, though under another name. So when the weight of scientific consensus tilted toward a future of GlobalWarming -- highlighted at the 1988TorontoConference on the Changing Atmosphere -- the CDC began thinking about the effect on mosquito breeding. Particularly worrisome was that such widescale warming might allow certain species of tropical mosquitoes to establish themselves as self-sustaining populations within the contiguous UnitedStates. Which I'll return to. But first, evidence that mosquitoes are adapting to GlobalWarming by extending their breeding season. And the spread of the asian tiger mosquito which has both the EPA and the CDC fretting.
posted
Does anyone remember a show on PBS (probably) hosted by an older british guy about global warming? (late 80s or early 90s) The premise was that he was living in (around) 2050 and he stepped into a holodeck-like aparatus that allowed him to show the "history" of the global warming problem...how we would talk and talk and not do anything about it until the coast lines were flooded?
For the life of me I can't remember the name of the guy or the title...
After the Warming. 1990. 2 videocassettes (55 min. ea.). Social journalist James Burke presents several possible scenarios caused by the greenhouse effect during the 1990's to 2050. Episode one presents various warming scenarios of the year 2050. What would our future hold if the scientists are correct, and if we take no action to slow the greenhouse effect? Episode two looks back to the 1990's from 2050, and traces various ways that man could respond to the growing environmental crises. VHS 1526
Posts: 54 | Registered: Apr 2005
| IP: Logged |
posted
I haven't watched it in years, but I recall it spelling out almost exactly how we would behave over the last 15 years...kind of spooky actually...I can't recall the "science" he used or whatnot, this was back when "greenhouse effect" was the buzz=phrase of the day...I just recall his discussion on our actions in facing the problem...not the effects of the GHE or whatnot...
Edit - ok, having found an old critique of the show, it probably wasn't worth digging up...funny how memories of things can differ from the actual experience...ha....
Posts: 54 | Registered: Apr 2005
| IP: Logged |
posted
Coral reefs are starting to die off all over the world, most notably, recently, in the Carribbean. The warmer waters and disease are the main cause of their deaths, and since it literally takes hundreds of years for coral to grow to any significant size, scientists are pretty much telling the people of the world that if they want to see coral reefs, to see them now. They may not be around in a decade.
Posts: 21898 | Registered: Nov 2004
| IP: Logged |
posted
For mistaben, mostly from the link previously mentioned to Lyrhawn:
A map of Antarctic bedrock currently above sealevel. Based on the various estimates I've run across concerning the amount of grounded above-sealevel ice on Greenland and Antarctica:
If Greenland and Antarctica melt, the ocean rises between 66to72metres/220to240feet: the minimum-to-maximum rise based on the volume of water contained in above-sealevel ice supported by land.
However, the icecaps' weight presses Antarctica downward into the Earth about 1kilometre/0.62mile; much like loading a boat will cause the boat to float lower in the water. And just as a boat will float higher when its cargo is removed, the Antarctic continent will rise due to isostatic rebound as its icecap melts. Taking into account the higher sealevel from icecap melting, and the ratio of the weight of the ice under sealevel to the weight of crustal material, land currently ~760metres/0.47miles under the ocean will rise above the new sealevel. So the melting of ice grounded on the ocean floor down to ~760metres/0.47miles under the current sealevel will also raise the height of the new sealevel after the melting, in the long run. Similarly Greenland; though to a lesser extent because its icecap isn't as thick, and a smaller percentage is being supported by the ocean floor.
Which means that a rise of 72metre/240feet is a more realistic minimum in the long run -- continental isostatic rebound occurs slowly after removal of the load -- when added to the heat-expansion of seawater's volume expectable with the rise in ocean temperatures which would accompany a total meltdown of the icecaps.
ie Basicly, I would expect the upward isostatic rebound of Antarctica and Greenland to cause the mantle pressure under the other continents to decrease, and thereby expect the other continents to sink a bit into the elastic mantle. Somewhat like one person getting off of a waterbed will cause the other person to sink deeper into it. So my guesstimate would be that any drop in the oceanic crust from the extra weight of water from Greenland's and Antarctica's icecap melting would be matched or more by a similar drop of those other continents.
Sometime after I wrote my earlier post, I realized the the effects aren't competing after all, as you've so wonderfully explained.
But as I was too lazy to think it through myself, so was I too lazy to edit/delete my post. Thanks for answering!
Posts: 105 | Registered: Oct 2005
| IP: Logged |
posted
Because the money that could be used for building walls for later, is better used building other stuff now. At least, that's the attitude of most people. New Orleans had plenty of time and money, over the last decades, to enhance levees. Alas, the money was funneled to other projects and, at least some of it, lost to local corruption.
Building a floodwall around New Orleans that can withstand a Category 5 hurricane will cost billions of dollars. I'd say it's probably more important that designing a new fighter jet, but I try to stay away from political debates.
Posts: 1813 | Registered: Apr 2001
| IP: Logged |
posted
1) The diversion of the Mississippi for flood control and into a concrete shipping channel has stopped the deposition of new soil on the Mississippi delta. Because of this, there is no replenishment of the large area of Lousiana's tidelands being washed away by normal ocean wave action. 2) Shipping channels dredged through Lousiana's barrier islands, tidal marshes, etc are allowing those ocean waves to penetrate deeper and faster, which causes faster stripping of soils along the Louisiana coastline. 3) There is the probability that GlobalWarming will cause a rise in sea-level by a minimum of 1foot/0.3metres within the lifetime of most of the people posting on this forum. With the aforementioned remote possibility that it could be as much as 20feet/6metres within the lifetime of Hatrack's toddlers.
Even excluding GlobalWarming effects, the coastlands south of the line heading west from NewOrleans are going to be underwater within ~50years due to the MichoudFault. Those mini-earthquakes that Louisiana has been experiencing have been due to another subsidence fault offshore southward in the Gulf of Mexico. Essentially the entire Lousiana coast south of the MichoudFault located beneath BatonRouge appears to be sliding down into that other fault in the process of becoming a part of the Gulf of Mexico. If you take a look at the predicted subsidence on the Lousiana elevation map at the bottom of page8, about half of the coastal area less than 3feet/0.9metres above sea-level will be underwater by 2050, with the rest being underwater by 2100.
If you compare that elevation map to this state map, LakeCharles, Laffayette, and BatonRouge will nearly be seaports by 2100. And NewOrleans will be an island city walled off from the Gulf of Mexico, connected to the mainland by a narrow strip of land between the MississippiRiver and USHighway10. ie Even excluding GlobalWarming, what would be now be a seawall capable of protecting NewOrleans from a category5hurricane would probably only afford protection from a strong category3hurricane in 2100.
posted
Don't need to turn to scifi: science alone comes up with horror tales. I added a few links above as examples.
Posts: 8501 | Registered: Jul 2001
| IP: Logged |
quote:Originally posted by cheiros do ender: Am I the only person who thinks most of us will be on Mars (on dead) by then?
I think you not only are, you should be. Short of someone inventing a teleporter, there is no way to move any significant fraction of Earth's population to Mars; and I plan to be very much alive in 2100, thanks.
Posts: 10645 | Registered: Jul 2004
| IP: Logged |
posted
The author's assumption about sea-level rise is ~30metres too high -- so eg Europe won't become a continent separate from Asia -- but here's a very nice hard scifi site containing illustratively-useful-though-inaccurate maps of the land-sea borders along with optimistic discussions about regional climates of a GreenhouseEarth.
Posts: 8501 | Registered: Jul 2001
| IP: Logged |
quote:The point is, I'm undoubtedly wrong--every climatologist is
Kinda fun "what if" scenario to read, but since the sun's still dimmer and less active than normal, since the world's average temperature has been dropping for the last 10 years, since the PDO is in a cold phase, since the Antarctic ice sheet is growing and the Arctic one is back to the 1979-2006 median levels.....
I'm not terribly worried.
I agree with the basic idea of "don't foul your nest" so I'm happy to recycle and use LED's and all that -- I don't want to breathe dirty air or drink dirty water...but I'm much more interested in my local environment than the global one.
Posts: 1323 | Registered: Aug 2001
| IP: Logged |