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.'"
Because of bouyancy, melting the ice which is floating in water will not raise sea level. The ice is less dense than water, ergo it floats on the water, but it displaces an amount of water equal to its mass. So when it melts into water, the level will stay the same. You can try this yourself with a glass of water and ice cubes. Mark the water line with the ice cubes floating, then let the ice melt and notice that it hasn't moved. This is elementary school physics.
You can try this yourself with a glass of water and ice cubes. Mark the water line with the ice cubes floating, then let the ice melt and notice that it hasn't moved. This is elementary school physics.
I was thinking for some dumb reason that the ice cap would be frozen salt water.
Well, taken literally, that is true. The problem is that when salt water freezes, most of the salt is left behind. The explanation is fairly simple: The water starts forming crystals, and the salt (mostly Na and Cl ions) don't fit into the crystal structure very well. So at the surface, the water molecules slowly join the growing crystal, while the dissolved salt ions don't. You do get some salt in the ice, because ice usua
I haven't done the calculations, but I've read from a reasonably reputable source, New Scientist, that the Antarctic contains enough water to raise the world's oceans 75 meters. I suspect at some temperature, thermal expansion of the ocean would be greater than 75 meters, but I'm guessing, from other stuff I've read, that it'd take more heat to do that, than to melt the Antarctic. In other words, for a small worldwide increase in temp, I think the melting Antarctic would be the dominant effect. Of course,
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.
Heat can be transfered away much more quickly by the flow of water around the floating ice than it can by just the air around the landlocked ice. I would think that the floating ice would melt much sooner.
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.
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.
True for floating ice, but there is also ice that is on land in the form of glaciers which will probably melt and run off into the ocean. Like in Greenland and Canada and places like that.
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.
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 [physorg.com], not just the reasoning but also the actual experiment to prove it.
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.
If what you said was true large portions of the earth should be underwater every summer.
When it is summer in the North, it is winter in the South- so it stays relatively in balance up until now.
The difference is, the South has a rather big landlocked continent- as it's ice melts, it freshens the ocean, but doesn't change the heat absorption. The North is an ocean under the ice- when it melts, it absorbs more heat, thus creating TFA's feedback loop. So what YOU say might be true within the next 34 years
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
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
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.
I've been following global warming for a long time now doing a lot research on the side for the last couple of years. Here are some facts about global warming. Some of which you hear and don't hear from the main stream media:
1.) The world appears to be getting warmer with many computer models showing an increase in global temperature.
The word you're looking for here is "thermometers".
3.) Apparently, the Earth magnetic field has decreased by 10% in the last 150 years (source: http://www.space.com/scienceastronomy/earth_magnet [space.com] ic_031212.html). I'm an electrical engineer and during my studies in particle physics, I learned that a particles velocity can be affected by magnetic fields. I believe it's possible that more of the Sun's radiation is penetrating the Earth's magnetic field due to it being weaker. 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?
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.
6.) The United Nations found that there is more Methane produced from livestock, which raises global temperature greater than CO2 by a factor of approx. 20, than any human caused CO2 combined (source: http://www.fao.org/newsroom/en/news/2006/1000448/i [fao.org] ndex.html)
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.
How can you explain the recent same climate changes on different planets? I doubt it's all those cars being driven there.
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.
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 years (source: http://www.breitbart.com/news/2006/08/21/060821191 [breitbart.com] 826.o0mynclv.html [breitbart.com])? Also, how do you explain huge ice ages on Earth? Were thse caused by huge carbon emissions or was it a small natural climate cycle that just happens? Were those climate changes, which are no doubt more extreme than what's going on now, caused by the combustion engine? I don't have answers and everyone seems to have an opinion including a Nobel laureate who says the answer is more pollution (source: http://www.cnn.com/2006/TECH/science/11/16/smog.wa [cnn.com] rming.ap/index.h
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).
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)
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.
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.
I've been following global warming for a long time now doing a lot research on the side for the last couple of years.
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 years
Wait - 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.
If you melt only the ice that is above the waterline there will be less ice below the waterline as the whole iceberg now weighs less and displaces less water to make it buoyant. You can't meaningfully melt only the ice above the waterline (or below the waterline). Your thought experiment is like saying: cut the top off the iceberg and hold the remaining portion of it down in the water using exactly the same force as the top of the iceberg used to exert, then melt the top of the iceberg and look at what happ
uhg, my inability to express this analogy is frustrating me. Your first paragraph is what I was posting about. If the only change enacted on the environment is to melt either the submerged, or non-submerged ice, and no other effect is allowed. While I was writing it, I was applying the logic such that you could replace the submerged half of the formula with dry land. If you break it out into two sperate formulas (submerged ice melting reduced total volume, non-submerged ice melting increases total volume) an
How does this get modded insightful? Have you EVER heard how buoyancy works? This is high school physics stuff, people - a floating object displaces exactly the same amount of liquid as it weighs - a floating ice cube that weighs a gram, displaces exactly one gram of water. It sticks up out of the water however much it needs to make this happen. When it melts, the gram of ice cube becomes a gram of water, which now changes the water level by exactly ZERO. Of course, in real life there are very subtle poi
This is a tipping point. It doesn't matter if global warming is manmade or a natural cycle. Cutting your carbon emmissions will not stop this feedback loop. Once reached, this feedback loop will continue until all the ice is melted during the summer, and there is NOTHING we can do about it with current technology.
Well, kids, the good news is, you'll be grown and jaded long before Santa closes up shop for good.
What I want to know is, when will the ice in the antarctic melt? Real estate is just too expensive, we could use another continent, especially once we flood the ones we've already got. d^_^b
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?
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.
There is a slight difference in the academic and scientific quality between the reports appearing in major scientific journals that note the correlation between record high levels of CO2 in the atmosphere and increasing global temperatures, compared to the sort of "research" that appears on Fox news.
The story appeared on "Fox news" in the USA, and references a story appearing in the British newspaper "Daily Telegraph", both of those news organisations are known to be the main global warming deniers in each of those countries. They both love running sensationalist, unscientific articles in order to discredit the real scientific research going on.
There were predictions back 40 years ago. Oh, things like ozone holes, stuff like that. NASA eventually started looking for them, but had some trouble at first. The holes were so f*** large that their computer software was rejecting them as impossible.
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.
Here's the thing. I doesn't matter if you are skeptical of the particular facts of a particular study. Even if you completely ignore global warming, the fact is that pollution is bad no matter how you slice it, and reducing it is a good thing no matter what your motivation is.
You are buying into the Corporate PR machine that is actually keeping the focus on debating how real global warmimg may or may not be so they can continue to delay the costly adjustments that they will eventually need to make to protect the environment. The problem is that the continued delay as we continue to spend time rebuffing their continual denials and half truths about global warming will make it less and less likely that we can do anything about it.
Global warming is real, and the only reason anyone expends energy denying it is because they don't want to pay to fix it. Do you think all these scientists from all these different countries are making up all this data just so they can stick it to the corporations? They have better things to do!
Even if cows are responsible for the production of more greenhouse gases than "industrialization" and automobiles (doubtful, but I'll argue with it anyway), the fact remains that animal agriculture *is* a man-made industry - thousands of years ago, people did not have mass-production farms that we have today. Regardless whether it's industrialization, cars, or mass-production agribusiness that's causing the problem, the real source is the same: human activity.
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!:)
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...
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 [agu.org]
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.
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".
You seem to know a lot more about this than the real scientists... maybe you should let them know! Seriously though, you're as guilty as glossing over things as those you criticize. How do you expect these "great forests" to grow without any sunlight because the sky is constantly overcast? How will our crops grow?
But the real problem is, clouds don't just reflect sunlight, they also trap heat. And guess which one they are more effective at? You can take a look at our solar system for a clue: Mercury's peak t
And it's also well documented that ice is increasing in areas like Greenland.
No it is not, according to RealClimate [realclimate.org]. Snowfall may be increasing at the interior of Greenland, but it's offset by an accelerated dumping of ice into the ocean at the periphery.
From RealClimate:
The critical point for Greenland is whether the increased rate of glacier motion more than compensates for the greater accumulation on the surface. While the broad picture of what is happening is consistent between these papers, the bottom
Sea Level? (Score:5, Funny)
Re: (Score:3, Informative)
You can try this yourself with a glass of water and ice cubes. Mark the water line with the ice cubes floating, then let the ice melt and notice that it hasn't moved. This is elementary school physics.
There are two things that will raise sea
Re:Sea Level? (Score:4, Informative)
http://www.physorg.com/news5619.html [physorg.com]
Parent
Re:Sea Level? (Score:5, Informative)
And by the time you get to college, you should have learned that the experiment does not work with saltwater [physorg.com].
Parent
Re: (Score:3, Funny)
Re: (Score:3, Informative)
Well, taken literally, that is true. The problem is that when salt water freezes, most of the salt is left behind. The explanation is fairly simple: The water starts forming crystals, and the salt (mostly Na and Cl ions) don't fit into the crystal structure very well. So at the surface, the water molecules slowly join the growing crystal, while the dissolved salt ions don't. You do get some salt in the ice, because ice usua
Re: (Score:3, Interesting)
Of course,
Yes, Sea Level Will Rise... (Score:5, Insightful)
Parent
Re:If it also means Greenland... THEN YES! (Score:5, Insightful)
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.
Parent
Re: (Score:3, Interesting)
Heat can be transfered away much more quickly by the flow of water around the floating ice than it can by just the air around the landlocked ice. I would think that the floating ice would melt much sooner.
Re:No change in sea level. (Score:5, Informative)
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.
Parent
Re: (Score:3, Informative)
Re: (Score:3, Insightful)
It does change sea level... a little (Score:5, Informative)
Search for 'salinity' in http://www.radix.net/~bobg/faqs/sea.level.faq.htm
Parent
And you are wrong also ... (Score:4, Informative)
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 [physorg.com], not just the reasoning but also the actual experiment to prove it.
Parent
Re:No change in sea level. (Score:5, Informative)
- 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.
Parent
Re: (Score:3, Interesting)
When it is summer in the North, it is winter in the South- so it stays relatively in balance up until now.
The difference is, the South has a rather big landlocked continent- as it's ice melts, it freshens the ocean, but doesn't change the heat absorption. The North is an ocean under the ice- when it melts, it absorbs more heat, thus creating TFA's feedback loop. So what YOU say might be true within the next 34 years
Re:No change in sea level. (Score:5, Informative)
Ice
~~~ = No change in sea level (or extremely small change)
Ice
Ice
~~~ = Increase in sea level
Land
-Rick
Parent
Arrgh! (Score:3, Funny)
Land
~~~ = Sinkholes?
Ice
Re: (Score:3, Insightful)
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
Re:No change in sea level. (Score:4, Funny)
Unless.... wait... [googles your post]
Parent
Re:No change in sea level. (Score:4, Informative)
In other words, the argument is over, global warming is happening, and it's far too late to play the blame game.
Parent
Re:No change in sea level. (Score:5, Informative)
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.
Parent
Re:No change in sea level. (Score:5, Insightful)
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 [realclimate.org]
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.
Parent
Re:No change in sea level. (Score:5, Insightful)
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:
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.
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).
In all your thorough research, you've never come across the name of this planet in printed form? Even once?
Wait - didn't you just tell us not to believe any temperature indicators that are 100 years old?
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.
Parent
Re: (Score:3, Informative)
Pwnt by english (Score:3, Informative)
While I was writing it, I was applying the logic such that you could replace the submerged half of the formula with dry land. If you break it out into two sperate formulas (submerged ice melting reduced total volume, non-submerged ice melting increases total volume) an
Re: (Score:3, Informative)
Of course, in real life there are very subtle poi
Like the Tundra Methane Story before this (Score:3, Interesting)
Re:Like the Tundra Methane Story before this (Score:4, Funny)
Parent
I'm a step ahead... (Score:4, Funny)
Bad News for Santa (Score:5, Funny)
Well, kids, the good news is, you'll be grown and jaded long before Santa closes up shop for good.
What I want to know is, when will the ice in the antarctic melt? Real estate is just too expensive, we could use another continent, especially once we flood the ones we've already got. d^_^b
Skeptical. (Score:3, Insightful)
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 [foxnews.com]
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?
Re:Skeptical. (Score:5, Insightful)
So you would also be skeptical of the claim that I may be a billionaire by 2040?
Parent
Huh? (Score:5, Insightful)
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.
Parent
Re:Skeptical. (Score:4, Informative)
The story appeared on "Fox news" in the USA, and references a story appearing in the British newspaper "Daily Telegraph", both of those news organisations are known to be the main global warming deniers in each of those countries. They both love running sensationalist, unscientific articles in order to discredit the real scientific research going on.
Parent
Re:Skeptical. (Score:4, Interesting)
Parent
Re: (Score:3, Insightful)
So instead we have to listen to those organizations who are the main global warming promoters in those countries?
Define "disproven". (Score:4, Insightful)
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.
Parent
Re:Skeptical. (Score:4, Insightful)
You are buying into the Corporate PR machine that is actually keeping the focus on debating how real global warmimg may or may not be so they can continue to delay the costly adjustments that they will eventually need to make to protect the environment. The problem is that the continued delay as we continue to spend time rebuffing their continual denials and half truths about global warming will make it less and less likely that we can do anything about it.
Global warming is real, and the only reason anyone expends energy denying it is because they don't want to pay to fix it. Do you think all these scientists from all these different countries are making up all this data just so they can stick it to the corporations? They have better things to do!
Parent
Re: (Score:3, Interesting)
Well
Re: (Score:3, Insightful)
Tekeli-li! (Score:3, Funny)
Liberal Lies (Score:5, Funny)
And in other news... (Score:4, Insightful)
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...
Once again... hacking the papers (Score:4, Informative)
Re:Oh please (Score:5, Insightful)
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".
Parent
Re: (Score:3, Insightful)
Seriously though, you're as guilty as glossing over things as those you criticize. How do you expect these "great forests" to grow without any sunlight because the sky is constantly overcast? How will our crops grow?
But the real problem is, clouds don't just reflect sunlight, they also trap heat. And guess which one they are more effective at? You can take a look at our solar system for a clue: Mercury's peak t
Re: (Score:3, Informative)
No it is not, according to RealClimate [realclimate.org]. Snowfall may be increasing at the interior of Greenland, but it's offset by an accelerated dumping of ice into the ocean at the periphery.
From RealClimate:
Re: (Score:3, Funny)
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