Slashdot Mirror
Ice-Free Summers Coming To Arctic
rocketjam writes "CNET reports that researchers from the University of Arizona and other universities have concluded that the Arctic will likely see ice-free summers within a century due to the increasing rate of global warming. The melting will raise ocean levels worldwide, flooding coastal areas where a substantial proportion of the world's population live. The increasing rate of ice melt is already having an impact on people and animals in the Arctic. Currently, researchers cannot foresee any natural forces that will counteract the trend."
You link this hurricane to global warming and I'll do a backflip (this is coming from a 6'1", 230 pound guy here). Hurricanes happen all the time, their intensity varies all about. It just so happens we now have the technology to record and note these hurricanes when they happen, so any data or information we have on them at this point in time is gonna be pretty flawed. You say that hurricanes are more common these last 5 years, and I'll say "we only have 70 years of data to look at".
Seriously though, the hurricane bearing down on New Orleans right now should give folks something to think about with respect to global warming.
Yes, indeed, it causes us to think about what it was like before Global Warming, when there were no hurricanes.
Global warming is as much a reality as global cooling, which happens quite frequently in the very short term past hundred years. The earth's climate fluctuates quite rapidly from year to year. CO2 levels fluctuate quite rapidly from year to year. It's a fact of the earth's geological history. What you fail to understand is that knowing global warming and cooling exists is completely different from suggesting that global warming is caused by man's exhaustion of carbon stores.
I am defenseless. Use your button. Mod me down with all of your hatred.
www.climateark.org/articles/1999/sunsmayp.htm
The above link is one of the many sites that have for a long time been casting doubt on global warming. It appears that sunspots may have the strongest effect on the planet's climate.
Didn't we just have a bet between two groups of scientists about the climate being cooler in twenty years. I remember that in the seventies we were worried about global cooling.
Remember, the ability of an object to float is not (directly) related to its density. Its related to its ability to displace water and its mass. The reason submarines float (or sink) is because their shape displaces a greater mass of water than the equivalent mass of water that would fill their volume.
If you take a piece of steel and put it in a bucket, it sinks and raises the volume of the bucket by the volume of the steel. Take that same piece of steel and form it into a boat hull and it will float -- and the volume of the bucket will increase by exactly the same amount even though all of the steel is not submerged.
Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
Uh, no.
Sea levels would stay the same.
The surface level in the Arctic would drop to sea level, rather than being slightly above it as it is now.
OK, so all of you knuckleheads that are responding to the parent post by making glib comments about no hurricanes earlier in history...... Read the post! Although I suppose you are corroborating my suspicions of the prevailing wisdom here, please note that the sea levels and flooding due to storm surge and such are what I was talking about. As the overall temperature increases, sea level rises leading to more problems with flooding. I might also say that more than one climatologist has suggested that more and stronger hurricanes might be expected from global warming as well.
Visit Jonesblog and say hello.
A really cool guy named Archimedies figures this out a long time ago. You might want to read up on his work. This is a good start.
Now, as far as the reflection of radiant and such, I never said that it wouldn't change anything. I just don't believe it will cause a cascading death spiral resulting in the extinction of mankind by mutant polar bears.
Remember, the north pole is cold for a reason. It gets very little direct sunlight. During the 6 months that it gets any sunlight at all, it is at a very low angle. The amount of heat absorbed or reflected by seawater vs ice sheets at that angle is much smaller than you lead people to believe.
Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
There's a VAST amount suspended above sea level. Melt this, and yes, oceans will rise.
What is it suspended by? If the answer is "more ice", then you're wrong. If the answer is "Greenland", then you're right. But from your wording, it sounded like we're dealing with the "you're wrong" one.
It's a well known fact that Europe (and presumably the rest of the world) went through a cold period in the Dark Ages (approx 500 - 800AD). Such periods are common and known as "mini ice ages".
You link this hurricane to global warming and I'll do a backflip
Start doing backflips sonny. This particular hurricane cannot of course be specifically blamed on global warning. However, one of the most consistent predicitions of modelling over the last decade and a half has been the expectation of an increase in the frequency and strength of extreme weather events. So we can say that this hurrican is not inconsistent with predicted climate change.
Start paying attention over the next decade or two. When you start getting one in a decade hurricanes several times a decade, or you get 4 or 5 hurricanes per season, you should consider yourself put on notice.
Better to be despised for too anxious apprehensions, than ruined by too confident a security. --Edmund Burke
Even in the article title it says "Sunspots may play role in global warming". How the h*$$ did you get that this article is casting doubt on global warming? It flat out states that global warming is occurring, but with possible influence from the sun. But nowhere does it say that global is not occurring.
What is sick is not that you were modded up, but that somebody on fox is reporting exactly what you are saying.
I prefer the "u" in honour as it seems to be missing these days.
melting ice isn't like pouring alot of new material into the oceans. it's already there. melting the ice that is already floating there displacing water won't affect the position of the sealevel at all. What it might do (assuming that global warming is fact, which all proven scientific evidence shows it's not) is cause changes in the motion of hot and cold water under-sea currents. This could potentially change global climate patterns (note: change != destroy).
For something to float, it must displace an equal mass of whatever its floating in. By definition, the north polar ice cap is displacing exactly its own mass in water
That's neither "by definition" nor in actual fact; significant parts of the ice in the arctic rest on solid ground. When that ice melts, it will raise the sea level. It won't be anywhere near as dramatic as when the southern polar ice cap melts, but it will have an effect.
However, when taking the different salinity into account, things change. As you know from Archimedes, the ice is displacing exactly enough water to offset its weight (that is, the displaced water weighs as much as the ice). The thing is, it takes less *saltwater* to do that than it would *freshwater*. So when the freshwater in the ice melts, the levels rise.
If you don't believe me, check this article, it includes a picture from an experiment.
I was recently in Barrow, AK where I spoke with some leading climate researchers with the Barrow Arctic Science Consortium. I spoke with several researchers with PhD's in varying fields, and people with NOAA and the National Wheather service. Many of them have seen drastic changes in sea ice cover over the past few years. The Ice now forms in the middle of December instead of October, and the break-up in early spring rather than June.Several of the Inupiat elders have seen even more drastic changes over the past eighty years.For someone to deny the existance of global warming seems ludicrous.
Formed into a ship and floating, it would displace enough water to support it's weight. Since steel is about 8x as dense as water, it would displace approximiately 8 cubic meters of water.
(I'm ignoring the density of the air, which is small enough to pretty much ignore this demonstration. And steel is more like 7.85 times as dense as pure water, but the exact figure will depend on which steel, how salty the water is, the temperature, etc. 8 is close enough.)
However, the original poster's point is correct when referring to ice, because the density is generally constant. A steel boat is different -- the density of the steel part is much higher than the density of the part filled with air.
That, and polar bears are mostly water, with a density close to that of water, so really any effect they'd have either standing on the ice or swimming in the water would be minimal. :)
Apparently, you failed to read and/or comprehend
Yeah and your so moronic it's a wonder that you figured out how to breathe ... now that we have the pleasantries out of the way ...
Another example that might help you out, take a glass of saline water at 50 degrees farenheit. Crank the temperature up to 80 degrees farenheit. Has the water level risen? Perhaps microscopically but it won't be noticeable to the human eye.
Not a very good example then, is it? Try reality instead. Try this one instead, take the worlds oceans, raise the mean temperature by a about 3C and you will get a sea-level rise of up to 5 metres. No problems of perceptibility there!
The point is that all this BS about archamedies principle and floating icebergs raising sea levels misses the real science of rising sea levels. Ie they are due to the steric effects of temperature on (liquid) water, not due to melting ice. Melting ice is indicative of the rate of climate change. The melting of ice shelfs (on land) will contribute, but the overwhelming contribution to rising sea levels will be the thermal expansion due to rising ocean temperatures. Or at least that is what our models predict.
(assuming that global warming is fact, which all proven scientific evidence shows it's not)
I see. And of course you have links to back up this assertion from respected peer-reviewed journals?
I could understand if you had asserted "mankind is not the direct cause of current global climate change." That's something that is quite disputed by various climatologists; so one could be forgiven for ill-advisedly "picking" a side. The problem though, is that your assertion that "all proven scientific evidence shows it's not" (i.e. global warming is not occuring) is absolute bunk.
That global climate change is occuring is a forgone conclusion, the data clearly shows trending towards average global warming and increased atmospheric co2. Current science is focused on change rates; specifically problems involving sampling history, techniques, statistics and force modeling. Without solid data and working representative models, it's very difficult to put forth a sound cause-hypothesis.
[Gaffen, D et al - Multidecadal Changes in the Vertical Temperature Structure of the Tropical Troposphere, Science vol 287, 18 Feb. 2000]
[Hegerl, G.C. and J.M. Wallace - Influence of Patterns of Climate Variability on the Difference between Satellite and Surface Temperature Trends, J. Climate vol 15, 2002]
Ok, we get your point. Melting floating ice masses doesn't directly change the water level.
There's still a lot of ice in the Arctic, and more in the Antartic, resting on land masses. When that ice melts, it will raise the sea level. And once the ice is gone, the earth will absorb more of the sun's energy.
Basically... there's a reason why scientists believe that global warming will cause rising oceans.
Anyway, you are losing sight of the bigger picture. The problem is not so much that a few island nations will be wiped off the earth (bye Japan, Phillipinnes...) The problem is not even the threat of more tornados, or extreme weather patterns.
No, the problem is the domnio effect. Sure, it might be ok to just melt the Arctic. But once you do that, you're probably well on your way to melting the Antartic. And once that's done, you may have expanded the deserts in some other part of the world, which may release even more CO2 into the atmosphere. Guess what? That will cause some changes too.
There has to be a point, beyond which the dynamics of the climate system change so much, that it is no longer self-correcting. And we're going to find out just where that point is.
"Any connection between your reality and mine is purely coincidental." -Slashdot
Yeah, I know. Damn that global warming, life was much better in the south before we had hurricanes...
... I wonder if the sarcasm will sink in, or will i recieve an inappropriate mod like parent? I'm thinking 'informative', how about you guys?
...it's really a sad day for America when we require a goddamn ACT OF CONGRESS to make our DVD players work properly. ~
Global warming is an ALTRUISTIC reason to persue alternative energy. But, precious few great social changes happened for altruism. Real social change almost always stems from reasons economic in nature.
The biggest reasons to persue alternative energy options are ECONOMIC in nature! If the United States were to aggressively persue alternative energy (biofuels, solar energy, geothermal, nuclear, etc)
the following things will result:
1) Money spent for energy stays in the US economy. It does not finance the next round of terrorism, it does not deplete the US economy worldwide, it stays here at home to pay for and feed US citizens.
2) The sovereignty and power of the US depends on the political stability of the most unstable political climate in the world - the Middle East. The peoples of the Middle East have been at war in various forms for hundreds of years! By developing energy sources from the homeland, we provide enhanced security and stability for the United States. If we aren't busy raping the Middle East, why would they be mad at us?
3) Jobs jobs JOBS! An extension of item #1, researching and building the infrastructure of solar arrays, geothermal plants, and semi-superconducting power transmission lines will create many thousands of jobs at home, rather than Arabia.
So, how about it, conservatives? It's not about "global warming" or some hippy-liberal agenda, it's about national sovereignty and economy. Are you game? Or are you more interested in pandering to the oil elite?
I have no problem with your religion until you decide it's reason to deprive others of the truth.
I agree. Earth will survive, it has for millions of years. Life will survive, just as it has. The same might not be able to be said for most of the life currently on the planet (read: humans). This isn't about protecting the Earth, it is about protecting the human species.
Or if by that you meant that fluctuations in solar output somehow magically gets smoothed over by the ecosystem, sorry. I'm no expert on thermodynamics, but if you increase the energy you're pumping into a system, there must be some effect. Energy doesn't just go away. The system's processes must somehow take it in, but they're not going to be unaffected. The energy equation must balance.
But yes, there are indications that Mars is also experiencing global warming. That means our own problem may be self-correcting in the short term -- or it may be a new long-term or permanent state of affairs, to which we may well be contributing to some degree but over which we may not have much control regardless, at least at this particular point.
To which I would reply, So what? That we can get away with polluting our atmosphere isn't a good reason to keep doing it. If this does turn out to be a false alarm as far as anthropogenic global warming is concerned, then I hope it's taken as a warning or wake-up call rather than an excuse to pollute more. Because if it's not our fault this time, there may yet come a time when it is. I'd prefer that we never reach it if we haven't already.
And the brethren went away edified.
1950 appears to still be the worst on record. That article also mentions that hurricanes seasons have a 25-year cycle.
It also seems we have had a bit of calm weather (hurricane-wise) for quite some time:
But don't let the real facts confuse you.
Mathematics is made of 50 percent formulas, 50 percent proofs, and 50 percent imagination.
Good logic here, but the model is much more complex. It's not so much about water levels as it is about energy.
With that much water being warmed up, there's a lot more activity in the biosphere, which changes many, many things. During the 1400's, altered weather patterns in combination with high tides created storms which ravaged population centers all along England's and Europe's coasts. And this was during a period of mini-ice age cooling, not heating.
It'll be interesting to see how we are affected.
-FL
While I appreciate your clever use of basic physics, perhaps you might allow some room for the idea that the earth is not completely described by the science you learned in high school.
One important phenomenon, as described excellently by another poster in this thread, is the the fact that ice is much fresher than ocean water, so the overall density of the ocean will (most likely) go down, and voile, sea level rises.
The second, as others have also elegantly pointed out, is that much ice is not currently displacing any water, so 100% the effect of its melting is to increase sea level.
There are non-sea level issues of vast importance as well. Even simple climate models show vast sensitivity to overall earth albedo (reflectivity) and they all show a feedback loop with accelerating warming when a substantive amount of polar ice is loss. The fact that we're seeing this melting now is pretty strong clue that warming is going to speed up.
Also of great importance is the contribution of this new fresh water (and thanks to decreased albedo a great deal more heat absorbed by the earth) to the hydrologic cycle, as water vapor is also an important greenhouse gas. If the melted ice becomes water vapor, you can expect - again - increased rates of heating.
And yes, the poles get less heat from the sun than does the equator - the transport of that heat is the ultimate source of all weather patterns. So a substantial change in that heat balance can cause vast disruptions in weather patterns. In addition the potential shutoff of the Gulf Stream and general thermohaline circulation, there are potential movements of large high and low-pressure patterns that can bring intense droughts and flooding to numerous places, in the same way that El Nino does. And since climate systems are strongly nonlinear, it's very hard to predict where and when those events might occur. The effect could be anything from a little more sun in places to life-threating droughts. Put it this way: if something like the North Atlantic Oscillation can set conditions for a devastating hurricane season in the tropical Atlantic (as we're poised to get), imagine what a climate change several orders of magnitude larger could involve.
You can argue all you like about whether these changes are majority anthropogenic or not, but it is indisputable that our carbon-loading of the atmosphere is like pressing hard on the accelerator when you're going down a steep incline. Carbon dioxide content is a big, big, lever for global climate, and I'm hard pressed to see value of taking the Wile E. Coyote approach to dealing with this particular change in our world.