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Arctic Ice May Melt By 2040
Dekortage writes in with a new study by the National Center for Atmospheric Research suggesting that the North Pole may be clear of ice in summer as soon as 2040, decades earlier than previously thought. From the article: "'As the ice retreats, the ocean transports more heat to the Arctic and the open water absorbs more sunlight, further accelerating the rate of warming and leading to the loss of more ice,' Holland said in the statement. 'This is a positive feedback loop with dramatic implications for the entire Arctic.'"
Does this mean the sea level will rise some?
Bite my shiny metal ass.
I've already started buying beach front property in Nevada.
True, but at least we will get some new shipping lanes out of it.
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Who can even make heads or tails of all this global warming stuff?
We get reports like this, within a day of getting reports like cows cause more greenhouse gases than cars, planes, and all other forms of transportation put together
Say what you want, but I'm quite skeptical of their ability to accurately forecast this stuff...haven't there been sensationalist reports like this for the last 40 years? All of which were disproven when more accurate methods of forecasting came around?
Ever notice how people that are skiing wear sunglasses?
That's because ice reflects sunlight.
Take all the energy that the polar regions reflect because of sunlight, and instead add it to the ocean in polar regions.
That's the math they're saying they did, and the answer they came up with is : the polar cap melts fast!
If you don't want to buy it, do a counter study. As is, their results seem fairly clear and robust. Not saying that they're exactly right, but a counter argument needs to be more then you saying "NOOOOOOO".
"it actually LOWERS the water level."
Wrong again. The volume of the ice submerged in the water is equal to the volume of the ice if it were water. The only difference between the water and the ice is density. Ice is less dense. Because of that, it floats. But the only part of the ice that floats above the water line is the difference in volume between it's forzen and melted states. Submerged ice melting in water leaves the water level at exactly the same place. It's not a centimeter, millimeter, or even nanometer different. It physically can't be different.
What does that have to do with it?
If I'm bleeding to death, the fact that the knife wounds are bleeding out faster than the gunshot wounds, and the fact that in the past I've gotten nosebleeds, so its not unusual for blood to be coming out of my body isn't really all that important. Dealing with the blood loss is.
No, no, no you have it all wrong, lets imagine a real future:
Arctic Ice May Melt By 2040
Posted by kdawson on 13:40 Tue December 12, 2043
Arctic Ice May Melt By 2040
Posted by Zonk on 12:10 Tue December 14, 2043
Arctic Ice May Melt By 2040
Posted by cmdrtaco on 17:40 Tue December 15, 2043
Arctic Ice May Melt By 2040
Posted by Zonk on 17:49 Tue December 15, 2043
Arctic Ice May Melt By 2040
Posted by Zonk on 23:34 Tue December 19, 2043
liqbase
My ability to work formulas and functions far exceeds my ability to express those formulas in the english language. ;) So here's a picture of what I was attempting to express.
Ice
~~~ = No change in sea level (or extremely small change)
Ice
Ice
~~~ = Increase in sea level
Land
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
- not all the ice that could melt is supported by water buoyancy.
- temperature changes of liquid water will cause change in density.
- polar bears will drown
The first is what could inhibit the Atlantic Conveyor by weakening its motive force : the downward flow of cooled salty water would be disrupted by large quantities of freshwater runoff from Greenland. Consequence - European weather becomes more like that on Newfoundland.The second mechanism is what will cause sea levels to rise - the average temperature of the ocean is more than 4C so an uniform increase in water temperature will cause expansion. As the ocean is quite deep in places, a small expansion could lead to a significant rise in water level.
Admittedly not everybody cares about polar bears drowning or European climate becoming too cold to make Champagne or low-lying island states in the Indian Ocean being obliterated. Selfish gits.
Because not all of the ice is floating. There is a significant amount of ice in the Greenland Ice Cap. Melting of this will cause the sea level to rise. Interestingly, it will also cause Greenland itself to rise by a small amount due to the release from the weight of the ice. There is also non-floating ice on the Canadian Shield islands. In addition, if you assume that melting of the Arctic ice cap will be accompanied by at least some melting of the Antarctic cap, there could be a sea level rise of from a few meters to several meters. This is enough to cause a severe disruption of human populations.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
If the North Pole melts alone... Then no.
But Chances are that Greenland will almost melt in the process.
Therefore we will notice an increase in sea level if the Arctic ice melts but it will be due to Greenland ice melting.
"I am the king of the Romans, and am superior to rules of grammar!"
-Sigismund, Holy Roman Emperor (1368-1437)
Wow, way to tack a COMPLETELY UNRELATED comment onto mine, since it's near the top of the discussion, and hope for an easy chance at higher moderation.
I made no arguments for or against global warming - I made a simple statement about the physics of ice melting.
And wow, you learned that electrical fields affect the motion of particles while studying particle physics, did you? I learned it in high school with everyone else. And you BELIEVE that Earth's magnetic field shields us from radiation? Why, that's dandy, considering the fact that scientists know this to be the case. For someone who supposedly has done "a lot of research on the side" about this stuff, you sure don't seem to have a clue as to what OTHER people already know.
But please, don't let that stop you from playing the game that every political website with an agenda plays, linking a bunch of articles trying to lead people towards one conclusion, while making no genuine connection between said articles. Nice touch with the not-so-subtle "I don't know the answer, but I'll ask a bunch of hypothetical questions that lead you towards my own foregone conclusion" routine.
isn't anyone worried about the antarctic? If it warms up there, more and more fools will make expeditions there, and awake the Old Ones!
The liberal moonbats are at it again. They're using all this "science" to provide us with "answers" about things which are essentially unknowable. And why? It's a vast liberal conspiracy that is meant to try and gain the hearts and minds of the weak willed and fey. But we modern conservatives are made of stern stuff!! We don't need "science" to tell us about the world around us. We use what's right in front of us: reality. If global warming WERE happening, which it isn't, it should be warmer outside today than it was in the past at this time of year. And even then, those liberals spin everything and flip-flop. You tell them that it's actually colder and they say that's a sign of global warming! What tricksters!! Well thankfully, the world has joined the conservative party and after the landslide win for Bush in 2004, it's obvious that things are NEVER going back. Don't believe in the lies that the liberals tell you or try to scare you with. It's purely scare tactics of a dying belief system. Instead, accept that as rugged individualists, we in the conservative parties will triumph over any adversity. We are strong. We are adaptable. Even IF global warming were happening WHICH it isn't, business would build special suits, vehicles and housing and create new materials to live on a hotter planet. The market will decide! And besides, my Enron stocks are way up there today. Thanks Cheney! :)
-"...bad old ideas look confusingly fresh when they are packaged as technology" - Jaron Lanier (Digital Maoism on Edge.o
That's not entirely true either. Fresh water is slightly less dense than salt water. So when the ice cap melts, the oceans will become fresher and less dense. Since the overall mass of the water+ice does not change, the sea level will rise slightly.
RTFA- Atmospheric CO2 or even methane has NOTHING TO DO WITH THIS FEEDBACK LOOP, except maybe for starting it. You could kill off every cow on the planet, shut down every CO2 producer, and the arctic ice would STILL be gone by 2040- because the cause (ocean absorbing more sunlight than ice) is a positive feedback loop that has already started.
In other words, the argument is over, global warming is happening, and it's far too late to play the blame game.
SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
I guess that 40 years ago, it would have been within the knowledge and ability of people to predict that cutting down the forests in Africa would cause a drought. Certainly, it's indisputable that humanly-deforested regions have suffered longer, more severe droughts since being deforested than at any time prior.
In recent years, there has been strong evidence that zooplankton levels are inversely proportional to temperature - cooler weather, more plankton; hotter weather, less plankton.
Does this mean that global warming is real? Define real. The globe is warming, that's irrefutable. Is it caused by human activity? Well, define activity - are you including deforestation, pollution, changes in the biological infrastructure of the planet, etc? Or just a select set of these? Also, and this is the billion dollar question, how much does the cause matter? If the planet is warming to the point where the current life is incapable of survival, who gives a damn about the causes? The latency inherent in the system is on the order of decades to centuries - changing the causes today won't be fast enough to stop the planet overheating, even if all causes WERE under human control. Why not take care of the problem right now and address the causes when we've got time?
I do believe humans are the primary cause, because although natural sources are often much greater, they are much more sporadic and much more regional. Humans have generated non-local sustained inputs, and those simply didn't exist before. Nor is the process linear. Not even remotely close. Saying that X is greater than Y by a factor of Z is only useful if you can use Z to make some useful observation. If the system is non-linear with both positive feedback and negative feedback loops that are themselves non-linear, you have what is known as a chaotic system. Chaotic systems have two properties - they are acutely sensitive to initial conditions, so any error in measurement will explode out of all proportion in almost no time at all, and they are non-differentiable, so that you can't accurately solve any given step even if you DID know the initial conditions. This means that you cannot directly equate human activity with natural activity and hope to get useful results. The best you can do is equate mechanisms and distributions to see what MIGHT be comparable.
However, my opinion of human activity is of no consequence. If humans cut out all pollution tomorrow, we would not start to see the benefits until a hundred or so years after global warming reached crisis point. If you want to do something effective, don't target the stuff that is pointless. Fixing human activity is like re-wallpapering a house that's on fire. Some things can be left to later.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
The word you're looking for here is "thermometers".
No, obviously not. The temperature was falling throughout those 150 years and has only started rising recently. The only correlated factor is CO2.
Complete crap. We have absolutely no idea what the temperature history of the other planets is and so we have no way of drawing any conclusions from any changes we see.
The article you linked to says that CH4 only amounts to 18% of CO2-equivalent emissions. Since the lifetime of CH4 is only 12 years, the cumulative effect is smaller still.
See above. However, since temperatures on Earth have only started rising recently, and we've been monitoring the Sun's output longer than that, we can be sure the reason isn't a change in the Sun.
2.) Tying a trend to warmer temperatures based on older data from the early 1900's is suspect at best. Good, reliable, accurate scientific equipment that measures the temperature wasn't readily available until recently (late 1900's).
j r.html [space.com])
This is why we use proxies to determine the temperature back then. There multiple datasets ranging from ice cores (we match the variations in atmospheric concentrations in more recent periods, and use the cores as a proxy to earlier dates), and tree ring data and so on. We generally don't use temperature records from early 1900s for precisely the above reason.
If more radiation hits the Earth, shouldn't that also increase the overall temperature of the Earth and can global warming be attributed to this?
But its different kinds of radiation. Magnetic fields affect charged particles only - aka solar wind and the aurora, and these have negligible energy input, especially relative to normal EM radiation which GW is about. Now, additionally, we have good data recently on the trends in both solar radiance and temperature forcing, and numerous papers have concluded that the sun itself can explain at most 30% of the observed trend. (Google scholar for the relevant papers)
4.) Jupitor is experiencing the same climate change that Earth is. (source: http://www.space.com/scienceastronomy/060504_red_
Check out the time frames! The dates given are 1998 - about 10 years.
Now, what do you think the orbital period of Jupiter around the sun is? Wikipedia has an answer 4333 days = 12 years. So, how interesting it is that we are seeing changes on the same time frame as Jupiter's passage around the sun, a passage that of course is not perfectly circular, in fact getting closer and further from the sun as time goes on...
What's more, there's another major factor - Jupiter's colour. Huge tracts of Jupiter's surface are in different colours, and as these vortices move about, obviously that is going to change its irradiance. Fortunately, Earth is not one big hurricane.
5. This is similar to Jupiter. Mars has an orbital period of 2 years, and has much greater eccentricity than Earth in its orbit. The temperature trend we have is over 3 years, a 1.5 cycles, something like between winter this year and summer next year. How mysterious that there would be a warming trend.
Additionally, there are dust storm factors as well: See http://www.realclimate.org/index.php?p=192
6. That source doesn't say that. Go read it again. Methane is more powerful per volume, and agriculture as a whole takes up more than transport. But transport isn't everything and the total volume of methane is small. Campaigners focus on transport, because transport is easier to cut than agriculture without killing bazillions of people.
Were those climate changes, which are no doubt more extreme than what's going on now, caused by the combustion engine?
They aren't. They happened over thousands of years and can be explained by a variety of other factors, whilst the current change is happening over decades and there is no other observed factor that can explain it.
Actually, no. Sea level will still rise: though only by a little. The water from the ice is less dense than the sea water around it because the sea ice typically contains less salt. Hence, more floats up above the water than bouyancy would suggest, which reduces the water level as it gets frozen, and increases the water level when the ice melts again.
l
Search for 'salinity' in http://www.radix.net/~bobg/faqs/sea.level.faq.htm
Must admit I accepted this too until the argument was put to me recently. Fact is of course that the ice is fresh water (less dense) than the sea water it floats in. Check out the links posted elsewhere to physorg about this. Archimedes principle is about the force of the ice pushing down and displacing an equal weight of sea water. But since the ice is lower density then the volume of sea water displaced is less than the volume of the fresh water in the ice ... even after melting. So when floating ice melts in sea water the sea level goes up. Check here, not just the reasoning but also the actual experiment to prove it.
Bitter and proud of it.
No, you haven't. You are a liar. You've been listening to ultra-rightwing propaganda lies and you're happy to parrot them blindly and unreflectedly. That's a difference.
Many have pointed out the utter absurdity of your gibberish. Here's a couple more examples:
2.) Tying a trend to warmer temperatures based on older data from the early 1900's is suspect at best. Good, reliable, accurate scientific equipment that measures the temperature wasn't readily available until recently (late 1900's)Shackleton recorded the annual extent of sea ice around Antarctica. We've been doing this for close to 100 years now. This IS a measurement of global temperatures.
Every harbor in the world keeps a record of the annual high-water mark at least since the British Empire. Every harbor in the world has seen the ocean levels rising for at least the last 100 years. This IS a measurement of global temperatures.
Weather related damages to the US agriculture (floods, droughts, hurricanes) have been tracked since Jefferson's time. This IS a measurement of global climate.
I'm an electrical engineer and during my studies in particle physics, I learned that a particles velocity can be affected by magnetic fields.You might want to call Joe's Diploma Emporium and ask for your money back: magnetic force (and thus acceleration) is always perpendicular to the velocity of a charge. No amount of magnetic fields can increase or decrease the speed of a charged particle (and certainly not an uncharged one).
Jupitor [...]In all your thorough research, you've never come across the name of this planet in printed form? Even once?
Is it possible that the warmer temperatures that Earth is experiencing are caused by cyclical natural phenomena? What about glaciers in Greenland that have been shrinking for 100 yearsWait - didn't you just tell us not to believe any temperature indicators that are 100 years old?
Were those climate changes, which are no doubt more extreme than what's going on now,You are so utterly mentally retarded that it hurts my teeth to read your drivel. NEVER in the history of the earth has anything happened that was even a tiny fraction of what we are seeing today. Not only were the ice ages NOT "more extreme", they were peanuts compared to what we see today. We have a pretty decent record of global temperatures for several hundred thousand years and there is no indication anywhere of global temperatures changing on the time-scales of decades or even centuries. Nothing like what we're seeing right now can be found anywhere in the earth's climate record.
I recommend that you refrain from posting about issues you do not have the shimmer of a clue about.
We're all born with nothing.
If you die in debt, you're ahead.
...it may not.
I'd like to nominate this for a really terrible piece of science reporting.
Number of probabilities reported: zero.
Number of fractional changes reported: zero.
I'm quite willing to believe that the loss of Arctic sea ice and the shrinking ice cap are significant and we should be worried (although not, of course, about the polar bears, who have weathered far greater climate fluxuations than this.) But this article gives none of the information that a rational person would require to make a judgment on the issue.
The science on global climate change is imperfect, but certainly not junk. The reporting on global climate change is another matter entirely...
Blasphemy is a human right. Blasphemophobia kills.
Here's the full abstract. Note that 1 of 7 computer models showed total ice melt by 2040... the worst case scenario. Gotta love how the media grabs the flashy stuff. Holland, Marika M.; Bitz, Cecilia M.; Tremblay, Bruno Future abrupt reductions in the summer Arctic sea ice Geophys. Res. Lett., Vol. 33, No. 23, L23503 http://www.agu.org/pubs/crossref/2006/2006GL028024 .shtml
Abstract
We examine the trajectory of Arctic summer sea ice in seven projections from the Community Climate System Model and find that abrupt reductions are a common feature of these 21st century simulations. These events have decreasing September ice extent trends that are typically 4 times larger than comparable observed trends. One eventexhibits a decrease from 6 million km2 to 2 million km2 in a decade, reaching near ice-free September conditions by 2040. In the simulations, ice retreat accelerates as thinning increases the open water formation efficiency for a given melt rate and the ice-albedo feedback increases shortwave absorption. The retreat is abrupt when ocean heat transport to the Arctic is rapidly increasing. Analysis from multiple climate models and three forcing scenarios indicates that abrupt reductions occur in simulations from over 50% of the models and suggests that reductions in future greenhouse gas emissions moderate the likelihood of these events.
Thanks.
Unless.... wait... [googles your post]
FairTax baby!