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Global Warming will Open Northwest Passage
Makarand writes "For the most part we dread global warming. However, some
experts from the U.S. Arctic Research Commission, studying the polar ice caps,
are now pointing out
some of the advantageous side effects of global warming.
They are predicting
that in 5 to 10 summers from now the
polar ice caps would disappear for around 2 months each year
opening up the fabled Northwest passage for commercial
shipping. This would effectively reduce the shipping
distance between Europe and Asia by 6800 miles compared to the route
using the Panama canal."
Nope. The northern Icecaps are floating. Their melting does nothing to change the global water level. The frozen water is already displacing as much water as it would in liquid form.
The rising sea levels due to global warming are/would be the result of the Antarctic and Greenland ice caps partially melting, which are on land and are enormous. Only minor melting of small, outlying portions, decreased global, glaciation, and increase movement of glaciers to the water all have a major impact.
It's also safe to assume that any influx of fresh water into the ocean will cause an even distribution of increased depth, but I know what you meant. :)
[1] The masses are necessarily the same, but the volume slightly differs because of the variance of the density of fresh to salt water.
Completely different parts of the world. The Suez canal, IIRC, links the Mediterranean and the Red Sea. The Northwest passage would be an alternative to the Panama Canal (which exists in central america).
The Northern ice caps are floating. QED, they displace as much water(by mass) as they themselves contain. There's a fresh water / salt water density difference, but not a huge one.
The rising ocean level concern has to do with melting ice *on land* (Greenland, Antarctica,) and with a nontrivial amount of thermal expansion to be expected by heating up the oceans. (Hey, it doesn't take many millionths of a percent of the ocean's volume to raise things a few feet.)
This isn't good news as far as Canada is concerned. The following is from an E2 w/u I did a while back (http://www.everything2.com/index.pl?node=Canadian %20Arctic%20Sovereignty):
Arctic sovereignty has long been a pressing issue in Canada. While ownership of the Arctic Archipelago islands is no longer disputed seriously by any nation (and the inhabitants of this region are professed Canadians), control over the surrounding ocean is still a contentious issue.
Canada claims full ownership of all the seas in the area up to its usual (and accepted) 200-mile limit, as well as full ownership of any sea ice extending northward from it's cost to the North Pole (since, in its opinion, sea ice is effectively land). Many countries, including the United States, refuse to recognise its sea ice claim - and while allowing that the open waters in the area are a Canadian possession, claim that the Northwest Passage (an indeterminate rout through the maze of the Arctic Archipelago) is an international strait that that they cannot be denied passage. This is despite the fact that the Northwest Passage is perhaps the least navigated waterway in the world (the number of ships which pass through it in a year can be counted on one hand, and most of these are government icebreakers).
The United States has, on a number of occasions, attempted to flout Canada's sovereignty by sailing both civilian and military vessels through the passage unannounced. Matters came to a head in the 70's when the United States attempted to navigate a reinforced oil tanker through the passage (an oil tanker break-up in the high arctic would have unimaginably disastrous effects), but public outcry forced it to concede to at least giving notice to the Canadian government before attempting any further navigation.
Also, Russia and the United States have both challenged Canadian sovereignty by sailing submarines under the ice and seas claimed by Canada. During the Cold War they would often conduct cat and mouse games in the area, much to the chagrin of the Canadian government. Canada currently does not have submarines capable of conducting under ice patrols, and does not expect to have this capability until around 2010.
To counter the moves of other countries and to assert its sovereignty, Canada has taken a number of steps. First, it has invested large amounts of money in the people of the area. The Inuit people of the region are provided with full health insurance and welfare (as are all Canadians), and recently efforts have been made to maintain as much of the traditional culture and economy as possible. Recently, the Inuit were even granted their own territory, Nunavut, where they comprise the majority of the population and Inuktitut (the tongue of the Inuit) is an official language. Recently, youth unemployment and lack of housing (because of the high birth rate and rapidly rising population) have both become a cause for concern.
Additionally, the government operates a fleet of icebreakers and aircraft used to supply far northern settlements and outposts. These have presented something of a Catch-22 for the government, since an arctic presence (largely by way of military vessels) must be maintained to assert sovereignty, yet these vessels breaking up the sea ice has a negative effect on local hunting activities (something the government would like to support).
The native people have also been employed directly to assert sovereignty by way of the Canadian Rangers, a program that employs Inuit hunters on the sea ice to patrol for foreign craft and assert Canadian sovereignty (the fact that many Inuit live a large part of the year on the sea ice also gives credence to Canada's claims).
Another aggravating factor in maintaining sovereignty is global warming. The Arctic has been disproportionately affected by warming, and it's expected that commercial navigation of the Northwest Passage will become feasible in the next 10 to 15 years. Many nations (including immerging Asian powers) would have an interest in opening up the passage to free navigation. Not only would such a scenario threaten Canadian sovereignty, but it would also cause immense harm to the lifestyle of the people of the region - and would contribute massive amounts of pollution in an incredibly fragile environment.
No it won't. If the ice is floating (rather than supported by a pile of ice reaching the bottom of the glass) the water level won't change one bit if the ice melts. (Neglecting evaporation, of course.) Say you have one gram of ice. For it to float, it must displace one gram of water. Now, ice is less dense that liquid water, so only about 90% of the volume of the ice is necessary to displace the gram of water. The remaining 10% is visible above the surface.
When the ice melts, the resulting liquid still only has a mass of one gram. Since one gram of water was previously displaced by the ice, the resulting liquid fits perfectly level with the water line.
- A physicist
-1, Wrong.
The block of ice floats because it displaces as much water as the ice weighs -- if a glass of water is at a given level with a block of ice of mass X grammes in it, then removing the block of ice would require one to put X grammes of water back in the glass to return the liquid to the same level as with the block.
As the block of ice melts, the water from the melting will combine with the water in the glass, tending to increase the water level in the glass -- however, there is now less ice in the glass, so it displaces less, tending to decrease the water level in the glass. As it so happens, for ice the equation is balanced and there ends up being zero net change in the water level -- as in the above example (removing the block), we just happened to remove the block (X grammes) by melting the ice (returning X grammes of water).
This isn't the complete story with regards to the ocean, of course, because the ocean isn't pure fresh water -- but the effects of melting ice in seawater would still be orders of magnitude less than you're predicting with an 'overflowing glass of water'.
"Evil company X is threatening to restrict our rights! Let's all get together to stop--OOOH! SHINEY!!!" -- AC
How about you try the damn experiment before you assume how it turns out.
Floating ice is not fully submerged because it is less dense. It's less dense and hence takes up more volume than the same mass of liquid water. Simple physics indicates that the *volume* that is submerged is the same as the volume the equivalent mass of liquid water would occupy (assumming the 'floating' is caused by the density difference and not jets you installed on the bottom of the ice...)
Do you think ice floats by magic?!?
Yeah I'm sure that would be a conern to the shipping. But it is manageable. Already North Atlanta Sea ice is monitored very actively in order to keep icebergs from hitting ships and oil rigs.
I believe the US Coast gaurd's International Ice Patrol takes care of most of the monitoring relevent to shipping.
The Northwest Passage is not, as the article says, "above Canada". The "tangle of islands about 500 miles north of the Arctic Circle" - those islands are all Canadian territory. The Northwest Passage passes through Canadian inland waters. Google for Northwest Passage and have a look for yourself. The USA usually respects the sovereign territory of its allies. Think the Canadian government might have something to say about commercial shipping polluting one of the last (semi) pristine environments left on the planet?
"Clean up the air and treat the animals fair" - Captain Beefheart
What did the us do there in the first place. It's Panama, not US, right?
For existing oil rigs they use the above, plus will actually tow large icebergs out of the way of oil rigs and the like.
A lot of the advanced tracking has actually only come on the last few years. NASA put up a satellite back in I think '98 that started tracking a lot of icebergs. This helped eliminate the problem of losing icebergs when they were being tracked by plane and ship based radar/sonar.
If the northwest passage opens up that will be a huge benefit for shipping. Not to downplay the other problems to the environment, but the west has wanted the northwest passage ever since Columbus first sailed the ocean blue.
Artic Information
The Canadian Department of Environment also has regular updates and warnings about icebergs and the like. Presumably were the northwest passage to open up they'd track it. (I admit I'm a bit leery of trusting the prediction - but who knows) I suspect that, baring continued war in the mid-east, the United States military would be involved as well. Admittedly it is less of an issue now that the cold war is over. But they have had quite a bit of monitoring of the arctic sea in the past.
Department of Environment
Wrong. Volcanic emissions of CO2 are approx. 150 times less CO2 than humans. (Link)
Warning: Some ideologies on the Net are smaller than they appear.
I think it is a rather interesting topic myself and one that the various governments with a partial stake in it should be further investigating. The northwest passages provides a very good alternative to the Suez canal, which has been closed twice since WWII, and could possibly get closed again if war were to somehow break out in that area. The northwest passage also eliminates over 3350 miles in the route from Trellheim, Norway to the west coast of Canada, which could improve trade between these areas.
The northern passage provides the most benefit for routes between northern Europe (Scandinavian countries, England, Germany, Russia) and the west coast of the US. For example, with the passage open, the route length between Norway and the West Coast of Canada would be cut by over 3350 miles (5391 km).
Positive effects are in the various IPCC reports. For example, my home country, New Zealand should improve the supply of power (NZ generates a good proportion of it's electricity from hydropower, increased tempertures should lower the seasonal effects on the power supplies). As another NZ example, the following is suggested: "Grain phenological responses to warming and increased CO2 are mostly positive, making grain filling slightly earlier and decreasing drought risk (Pyke et al., 1998; Jamieson and Munro, 1999). Although grain-filling duration may be decreased by warmer temperatures, earlier flowering may compensate by shifting grain filling into an earlier, cooler period."
All of this was taken from Climate Change 2001: Impacts, Adaptation and Vulnerability by the IPCC.
Warning: Some ideologies on the Net are smaller than they appear.
But the ice on Greenland and Antarctica (which is greater than the amount on the Northern cap) still will melt. And then there's the fact that the oceans will get warmer from the melting ice, and the warmer water is, the more space it displaces. So there will be a non-trivial rise in the oceans, but it will take some time. Luckily I will probably be dead (unless I discover the secret to immortality).
Two things are infinite: the universe and human stupidity, though I'm not yet sure about the universe. - A Einstein
Actually the melting of sea ice does have several, albeit indirect, effects on the sea level, since it influences world climate.
Firstly sea ice is white, the sea is not. So melting the ice lowers the albedo in the polar regions, which will have a small warming effect as less heat is reflected.
Secondly differential melting and freezing at the base of the sea ice is a major driving force in several ocean circulation systems, notably the 'Gulf Stream'. This plays a major role in transporting heat around the globe, especially to North West Europe and Iceland. It is believed that extensive reduction of the sea ice will reduce or even eliminate this current. There is evidence that in the last few tens of thousands of years the current has turned on and off several times.
Regional changes are likely to include colder winters and drier summers in western europe, and warmer waters and thus potentially more active tropical storms and huricanes in the Gulf of Mexico, although these changes would also depend on the (unpredicatble) response of other major ocean currents to the change.
Exactly what effect such a large change would have on overall world climate is difficult to predict, but since our current population and land-use patterns are based on existing climatic conditions, the maxim of 'any change is likely to be bad for us in the short or medium term' probably applies here.
What happens when the ice finishes melting?? The water temperature rises.
Ice acts as a thermal buffer. It keeps the water temperature near freezing... When it gets too cold, freezing ice releases heat as it freezes. When it gets too warm, melting ice eats a lot of thermal energy.
As the size of the ice drops, it's ability to regulate the temperature lessens. Temperature swings in the northern hemisphere are going to get larger and generally go towards the warmer. (I'm guessing that this has something to do with the already noted amplification of global warming in the far north).
Of course, Europe could be the ones that get royally worked over in the long run.... if the predictions mentioned on slashdot some time ago come true about the shrinking icecap messing up the ocean currents that keep europe unusually warm for their latitude.....
Great: You can get from Japan to Europe far faster, but most of the farms in Europe are now frozen over for most of the year. (kinda like the George Karlin skit: "The good news is that you'll live to a ripe old age, but you'll be bleeding from both eyes for the whole time")
OS Software is like love: The best way to make it grow is to give it away.
now you are talking science fiction here. we (mankind) are in no way capable of developing a system to control climatic conditions on earth based on nano-sized robots real fast. sorry.
ok, i have to admit, that we can develop a nanotech-based weather-changing system real fast. faster, at least, than nanotech terraforming other planets... oh: and cheaply!
--
"gallia est divisae in partes tres, quarum unam incolunt belgae, aliam aquitani, tertiam, quo ipsorum lingua celtae, nostra galli appellantur."
de bello gallico
the computer is online
i am not at it
what a waste of ressources
I'm not sure about shaving distances, but you might be able to shave some time. The Suez Canal is a congested area. Ships often lose a couple of days just waiting in line to go through. There might also a size/drafts/beams consideration. Supertankers, for instance, probably can't go through Suez.
Actually one of the main uses and design considerations for the Suez was to accomodate supertankers.
Please mod parent down. It is spreading false information.
Work on the Suez Canal began in 1859 and the canal opened in 1869. That's a little bit before supertankers were built.
Five years later the Lusitania is sunk by a torpedo, with considerable loss of life. The British had a blue ribbon committee look into her design. They suggested that there would have been less loss of life if she had not had a longitudinal watertight bulkhead.
My recollection is that some of the same people sat on both committees.
As water filled up some of the compartments on one side, the ship started to list to one side. Once she was listing more than, IIRC, fifteen degrees, then passengers couldn't jump across to the lifeboats on the lower side. And while passengers could enter the life boats on the higher side, lowering them was a problem, because they slid down the side of the ship, and in those days the hull plates were sealed with big rivets. The boat deck was sixty feet from the water. Those rivets tore the lifeboats to peices.
Canada may claim it is territorial waters, but the US has a stronger case in the claim that it's still an international strait and free passage cannot be denied or taxed.
Ironically, Canada itself contains one of the best precedents of this - the St. Lawrence Seaway is an international strait from the Atlantic Ocean to the Great Lakes, even though substantial stretches of it are Canadian territory on both banks. (Other stretches have Canada on one side, the US on the other.)
There's also the pesky fact that the Canadian waters do not cover the entire distance - the western terminus will be in either US or Russian waters, and the US could use Canada's own claims to claim all sea ice and surrounding waters to the North Pole itself.
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
In contrast, think about oil and water. Oil, for example, is significantly less dense than water and floats on water as a liquid. So, similarly, imagine some substance, which we'll call "blunge", that acts just like water does (with its relatively unusual decrease in density as a solid relative to liquid) but that both as a solid and liquid it's substantially less dense than water. What would happen?
Frozen, a chunk of blunge would float like water ice does and it would displace a mass of water exactly equal to its mass. Let's call the volume of displaced water x. When blunge thaws, it will no longer displace the water and the water level will fall....but then this liquid blunge, which has volume y, will float on the water and, theoretically (ignoring other factors), will be distributed evenly over the surface of the water. Now we have to ask: is the volume y equal to the volume x? No, we know that y is greater than x. For this reason, the level of the two fluids, with liquid blunge floating on top of the water, will rise relative to the level of water with solid blunge floating in it.
And, as it happens, this is the case with sea water, ice, and melted ice...fresh water. Fresh water is slightly (for these purposes) less dense than sea water; and so when north polar ice thaws, the seal level does, in fact, very, very slightly rise. When the ice in your soft-drink melts, the level very slightly rises. But it's negligible. The naysayers in this thread are technically right, but conceptually wrong.