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Post by Andrew on Sept 20, 2012 7:21:58 GMT
It is well known that the warm water below sea ice is prevented from reaching the cold ice many hundreds of feet above it due to the halocline, created by fresher water sitting on top of denser more salty water.
Arctic ice is therefore a blanket that keeps the Earth warm.
Acting against this phenonema of a warmer earth is the albedo effect which protects the arctic ocean from the full heat of the Sun.
However the ability of an open arctic ocean to cool the Earth must surely be far greater than the impact of the ice covered sea to cool the earth?
But if you read any climate text you will always only see that only the albedo effect is important and no mention is made of any competing force.
There were for example "unprecedented" Arctic storms this August where a storm not only warms the water by friction but also enables the warm water far below the ice to reach the ice to melt it.
It makes sense that an open arctic sea might have more storms and therefore be capable of losing the Earths heat more quickly
At some point the deep oceans will become colder and then you just need some circumstances for the ice to begin forming again, for example higher surface temperatures and colder deep water temperatures could create very large fresh water flows into the arctic and cause a fairly rapid refreezing.
Curiously the melting ice and warmer air temperatures could be simply cooling the oceans and setting us up for the next period of Arctic ice growth
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Post by numerouno on Sept 21, 2012 9:18:55 GMT
Iceskaters, you only need to explain why a high March sea ice extent will not lead to a high September sea ice extent, but ice will melt anyway, without requiring any storms.
If you observe the volume and extent trends, they are pointing downwards. Not rewarding your theory at all.
If there is a mythical storage of "warm water" in the Arctic Ocean, hmmm ... how come people have not found one, and if assuming there is one, how would it have come about, and what source would the heat have originated from?
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Post by icefisher on Sept 21, 2012 11:02:57 GMT
Iceskaters, you only need to explain why a high March sea ice extent will not lead to a high September sea ice extent, but ice will melt anyway, without requiring any storms.
I was suggesting earlier that a better indicator of recovery would be enlarging winter maximums as it has to work against a saltier arctic ocean which should result from less ice in the arctic.
Its the same issue as people worried about glacier loss, the communities living on glacial melt have water shortages as the glacial surface melt area gets smaller.
So less ice begets saltier surface water for the arctic.
It would be interesting to see data on surface temperatures of the arctic ocean. Our lady scientist making her first trip there from NSIDC was noting surface water temperatures of -2 to -3C. Thats pretty darned cold water (26 to 28 degreesF). The surface water needs to be pretty salty to get that cold without freezing.
So winter maximum has to deal with saltier water making it more difficult to freeze ice and the absorption of solar rays due to the loss of albedo both pointing at less winter maximum ice (at least from the point of view of a big proponent of albedo feedback that is the case). Whereas the summer minimum is aided by both these feedbacks.
So naturally under those assumptions the summer minimum recovery would trail a winter maximum recovery.
What really needs explanation is why the winter maximum has been increasing the past couple of years or so instead of the pattern we have seen over the longrun of both winter maximums and summer minimumsdeclining. Will that same pattern be the result this year? If you think you have an answer join the winter maximum poll thread and take a position.
Radiant is asking the question I have asked many times here. Ice is an insulating blanket. The arctic is a net loser of heat. So does removing the blanket and despite what is very low solar ray absorption does removing the blanket have a greater effect than net albedo effects.
So it seems to me you are asking Radiant to explain why what we are observing is consistent with the hypothesis when clearly such an observation is consistent with the hypothesis.
I think its on you to explain why high winter maximums would be consistent with your belief.
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Post by numerouno on Sept 21, 2012 11:04:48 GMT
"I was suggesting earlier that a better indicator of recovery would be enlarging winter maximums as it has to work "
Then how come it did not work in 2012? This is no "belief" but a fact! Quirky Physics not obeying Mr Icefisher, again?
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Post by numerouno on Sept 21, 2012 11:12:51 GMT
Icefisher, Tamino has performed a Fourier analysis on the yearly Arctic ice cycle already if you want to take a look: tamino.wordpress.com/2012/08/29/ice-over/The take-home message is that the high winter extent is no longer a proof of a high summer extent, but on the contrary in fact!
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Post by icefisher on Sept 21, 2012 12:37:29 GMT
"I was suggesting earlier that a better indicator of recovery would be enlarging winter maximums as it has to work against positive feedbacks of low minimum ice " Then how come it did not work in 2012? This is no "belief" but a fact! Quirky Physics not obeying Mr Icefisher, again? It did work against positive feedbacks and still came in larger than average. In antarctica the sea ice maximum is right now setting record high levels against positive feedbacks of global warming. Winter maximums have to fight against saltier water (lower freeze point - so less ice will form than if it were fresher water) and fight against heat absorbed into the ocean in the summer via the loss of albedo. Perhaps you might like to take a shot at explaining why these growing maximums are consistent with continued ice loss or alternatively why summer ice is a better indicator of what is coming than winter ice maximums. I mean some argument besides "if it bleeds it leads".
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Post by Andrew on Sept 21, 2012 13:03:02 GMT
Iceskaters, you only need to explain why a high March sea ice extent will not lead to a high September sea ice extent, but ice will melt anyway, without requiring any storms. If you observe the volume and extent trends, they are pointing downwards. Not rewarding your theory at all. If there is a mythical storage of "warm water" in the Arctic Ocean, hmmm ... how come people have not found one, and if assuming there is one, how would it have come about, and what source would the heat have originated from? At the moment you do not seem to be following what i am saying at all. 1. A high ice cover means a rising heat content of the earth with lower arctic air temperatures - warm atlantic water cannot fully lose all of it heat because of the protective thermal blanket created by the ice and salt water combination 2. Rising heat content leads to higher rainfall and greater build up of ice where normally most rain falls nearest the equator 3. Eventually the heat content of the earth is sufficient that the arctic ice begins to break up and the earth begins another long phase of cooling 4. Eventually the earth is sufficiently cool that the ice reforms and the heat content of the earth begins building again www.whoi.edu/oceanus/viewArticle.do?id=9206 “The halocline provides a barrier that shields the sea ice cover from contact with deeper, warmer waters,” said WHOI physical oceanographer Al Plueddemann. “This protects Arctic ice from melting.” Currently there *is* warm atlantic water under the halocline. The process does not have to be a cycle as such. It just needs some random weather factors to throw things either one way or the other but at either extreme it tends to rebalance. Ie 1. No ice means greatest heat loss 2. Maximum ice means minimum heat loss The process is very counter intuitive
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Post by numerouno on Sept 21, 2012 14:24:02 GMT
"At the moment you do not seem to be following what i am saying at all."
Why would I need to follow something that obviously is not taking place?? If reality is not in agreement with your theory, adjust your theory, not reality!
Your oceanic system is leaking water at a great pace -- the Arctic Ocean is a relatively shallow Mediterranean sea!
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Post by numerouno on Sept 21, 2012 14:37:47 GMT
"Perhaps you might like to take a shot at explaining why these growing maximums are consistent with continued ice loss or alternatively why summer ice is a better indicator of what is coming than winter ice maximums."
Icefisher, I think you have in fact described yourself why Arctic ice melts fast in the summer. Can you figure it out from what you wrote?
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Post by Andrew on Sept 21, 2012 16:25:52 GMT
"At the moment you do not seem to be following what i am saying at all." Why would I need to follow something that obviously is not taking place?? If reality is not in agreement with your theory, adjust your theory, not reality! Your oceanic system is leaking water at a great pace -- the Arctic Ocean is a relatively shallow Mediterranean sea! Numerouno ?? The arctic ocean has an average depth of over 1000m There is a halocline Warm Atlantic water is passing at depth under the ice and the halocline does prevent the heat of the atlantic melting the arctic ice The arctic ice and halocline does keep the arctic atmosphere colder than would otherwise be the case The earths total heat content is unknown
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Post by numerouno on Sept 21, 2012 17:14:16 GMT
"The arctic ocean has an average depth of over 1000m" The average depth of the Earth's oceans is 3790 meters. "There is a halocline" Goodness, and how much has it got to do with temperature? "The earths total heat content is unknown" Only a very small fraction comes from the Earth itself. I'd be very worried if it had actually changed a bit in a million years. People have actually studied the flow: psc.apl.washington.edu/zhang/Pubs/zhang5_15_98.pdfThe Arctic Ocean is massive, but so are the currents. I can't imagine you Mr Iceskaters shoud be so ignorant of this, surely having witnessed the daily sea ice motion this summer. These are no kid pools. "The arctic ice and halocline does keep the arctic atmosphere colder than would otherwise be the case" Apparently this supposed cooling is not enough at the present time!
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Post by dontgetoutmuch on Sept 21, 2012 17:37:35 GMT
Radiant, I don't think you understand the catastrophic global warmers supporter's position on this subject. What you are suggesting sounds dangerously close to negative feedback.
Negative feedback does not exist, therefore you must be wrong, and ridiculed for your blasphemy. If you keep this up you can expect rioting in the streets, because everyone worthy knows that we are doomed, and it is mankinds fault. Now it sounds plausible that a layer of ice and snow (And a couple of feet of snow with tiny air bubbles in it sounds like a great insulator.) would keep a warm ocean from dumping heat into a vastly colder atmosphere at the pole, with the heat rapidly escaping to space. If this was true, then less ice would mean more heat lost to space. But this is just silly. The sun, you see, without that ice, the sun shines down on the dark water, and well the albedo, without the ice, everything is just going to burn. And don't forget the evil CO2, is busily working to trap the heat yeah. So you are provably wrong. Forget your theory and embrace the reality! Oh, and for your sin, please donate ten grand to the mikey mann legal defense fund, or he might have to show his data, and nobody wants to see that!
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Post by Andrew on Sept 21, 2012 18:14:12 GMT
Radiant, I don't think you understand the catastrophic global warmers supporter's position on this subject. What you are suggesting sounds dangerously close to negative feedback. Negative feedback does not exist, therefore you must be wrong, and ridiculed for your blasphemy. If you keep this up you can expect rioting in the streets, because everyone worthy knows that we are doomed, and it is mankinds fault. Now it sounds plausible that a layer of ice and snow (And a couple of feet of snow with tiny air bubbles in it sounds like a great insulator.) would keep a warm ocean from dumping heat into a vastly colder atmosphere at the pole, with the heat rapidly escaping to space. If this was true, then less ice would mean more heat lost to space. But this is just silly. The sun, you see, without that ice, the sun shines down on the dark water, and well the albedo, without the ice, everything is just going to burn. And don't forget the evil CO2, is busily working to trap the heat yeah. So you are provably wrong. Forget your theory and embrace the reality! Oh, and for your sin, please donate ten grand to the mikey mann legal defense fund, or he might have to show his data, and nobody wants to see that! It is a pity that Steve is no longer around. He was quite helpful and prepared to explain his beliefs
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Post by numerouno on Sept 21, 2012 18:19:17 GMT
"Negative feedback does not exist, therefore you must be wrong, and ridiculed for your blasphemy"
Well as I said, apparently this supposed negative feedback won't work here to the effect some people HOPE it would, and we have the ice continuing to melt!
Sorry folks, it's a no recovery no summer ice situation we have at hand here. As some always say, it's nothing new in the Arctic, and probably something entirely natural ....
Could even be the same natural cause that is fast melting the glaciers in the Alps ...
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Post by sigurdur on Sept 22, 2012 0:23:50 GMT
What one has to examine to understand current ice/albedo etc , is that if you look at the MWP you will see a very simliar climate as present.
The resolution of proxies now under study show that during the MWP there were periods of fast warmth, as well as periods of fast cooling. That is weather.
Climate wise, there was a long period of warming, than a somewhat dramtic period of cooling. No one knows why the warming was occuring. There are hints that the cooling was enhanced by volcanic activity.
Whatever the cause, the temps fell enough to be called the Little Ice Age. Let's hope that we don't repeat this. After the Roman Warm Period, the temp also fell, altho it appears not as fast as the later MWP timeframe.
Numerouno was looking for cycles earlier. There are most deff climate cycles.
Let's hope that the present warming is not the last grasp of warming that occurs near the end of each interglaclacial period.
I much prefer the warmth for growing crops than cold.
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