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Post by icefisher on Jan 5, 2013 8:29:47 GMT
Radiant I read a paper about a year ago on this super cooling process and its likely relationship to the thermohaline circulation system. I think you are right that it does not penetrate the Arctic halocline Thats because the salty water never gets on top of the halocline. Anything on the top of the arctic halocline has to be as fresh or fresher than the water below because warm salty water is heavier than cold fresh water. There is no mechanism to lift the saltwater up on top of the halocline at any temperature to any important degree. The paper I read dealt with the supercooling process and the sinking of this water as a mechanism for the thermohaline circulation. It didn't go into variability of how much ocean surface area is available for this process but that seems to be a logical next step in estimating the volume of the process and its variability. Unfortunately I did not bookmark the paper so at some point I will have to hunt it down again. But essentially there are not many candidate processes that can explain this. Cold upwellings near land are common, in the middle of the ocean it seems to occur at the equator, probably an element of forcing from the thermohaline current system. Winds are important to all this and wind patterns is how ENSO is currently mostly forecasted. The mid ocean upwelling is poorly understood. All I am doing here is laying a candidate process for variability in the system both temperature and ice. It seems almost certain likelihood the icecap insulates the arctic ocean like an igloo insulates an Eskimo. Problem is all the sycophants in the world are looking for heat going to the bottom of the ocean and simply can't see what is happening right in front of them. It also can explain, to some unknown extent, perhaps why negative feedback is seemingly dominating. I think this might explain to some extent the PDO. It doesn't explain I would think the LIA recovery that has been postulated to underlie the temperature fluctuations from the PDO. Ice insulating the warmer water is a known factor so that is not the issue that was interesting me. I dont like the super cooled water idea in an impure salty ocean. However when sea ice forms in calm conditions the salt is not trapped in the ice and therefore I suspect the more salty layers now have to be cooled further to freeze and maybe this has been referred to as super cooling? A thin surface layer of very cold water could easily dip down by some wave action to punch thru the lower layers. Another factor to consider is that is it wrong to say that heat rises (by convection) when the source of heat is not at the bottom of the ocean. Instead because of the long time interval required to cool an ocean to the lowest layers the heat in the water will eventually be distributed by conduction thru the water. This observation applies also I realised recently to an oxygen nitrogen atmosphere where it is not obvious if the upper atmosphere would rise to very high temperatures without so called green house gases present. An interesting question though is how long will it take to warm the Arctic ocean? and therefore how much cooler could it have been in the past when salt water freezes at -1.8C? A much colder arctic would eventually mean there was no fresh water entering the system and so the external ocean currents would be in contact with the ice and transport the fresher melt water out of the Arctic until sufficient ice was melted that the arctic area warmed up again to allow fresh ground water to travel into the sea I would have to dig the paper up again to answer your question as I don't recall the range of subprocesses that were discussed. But it might be one of two mechanisms or both. 1) In the ENSO at depth analysis we see plumes of water moving up in the water column. As cold water sinks it cools the water below it and the constant stream of really cold water plumes downward to the bottom. 2) When saltwater freezes it sheds salt, these very cold salts could be aiding the process. In particular these major ice edge retreats are followed by record extent refreezes of water over various salt content sending record amounts of very cold salt into the water column below the ice.
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Post by thermostat on Jan 6, 2013 4:51:17 GMT
Great links Thermostat! As for Ice Volume Chart, does it includes Greenlands Ice Volume? If not, could you get that for us? In second link is noticeable that there aren´t summer temps anomalies throug years 1958 to present, but rather fall-winter positive anomalies that show a building up trend. Yes, it seems likey that a record melting season plus a couple of summer polar storms such this past year´s could lead to an unprecedent largely ice-free Artic in 2013... Even if natural variables trend could be turning to cooling now it will take them a few years to build up and reverse? My own guess-conclusion: we could have a record shrinking of our Artic Ice within now and a couple of years, but the trend then might reverse anytime, and if solar forcing theories are right that´s happening now and should show up coming years... Please share your analysis, for is best welcome to me! karlox, In response to your questions, first about the Greenland Ice; this is an ice sheet and not sea ice and it behaves differently from sea ice. It is not included in the Piomas calculation. A graph from 2012 by Greenland expert Dr. Jason Box can be found here in Figure 5.19 www.arctic.noaa.gov/reportcard/greenland_ice_sheet.htmlRegarding the DMI temperature record and summer temperatures, you are quite correct. For summer temperatures the daily mean temperatures of the Arctic area north of the 80th northern parallel are consistently slightly above 273.15 deg K (0 deg C) from day 150 to about 250 (basically, June, July and August). There is a straightforward physical process that is responsible for this summer specific phenomenon. That is, the Arctic Sea Ice is always no warmer than zero deg C. It absorbs heat from the adjacent air, cooling the air. As long as the ice cover persists, surface level temperatures over the ice will remain close to 273.15 deg K.
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Post by thermostat on Jan 6, 2013 5:43:19 GMT
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Post by thermostat on Jan 6, 2013 7:04:23 GMT
I suggest that relevant to the Arctic Sea Ice the open water in the far North Atlantic is of interest. This open water adds a substantial amount of heat to the Arctic climate system. I think that the recent discussion on movement of water between the Arctic, Atlantic, and Pacific oceans relates back to my recent post about the effect of the heat being added to the Arctic climate system. Heat is obviously being added to the Arctic by solar irradiation of ice free Arctic water. This is new heat being added to the global climate system. Regardless of how such heat subsequently moves around, this new heat added to the Arctic Sea provides energy for warming.
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Post by thermostat on Jan 6, 2013 7:33:48 GMT
Given that energy has been added to the Arctic Sea due to heat added to open Arctic water, the observed melting of Arctic Sea Ice, especially the loss of Arctic Sea Ice volume, indicates that a substantial amount of heat has recently entered the Arctic system. I agree, the physical processes that have directed these observed events have not been adequately described. In particular, the physical dynamics of heat transfer (as icefisher has said) are not clearly understood.
The fundamental observation remains that the Arctic Sea is presently melting.
Since it takes heat to melt ice, and ice has clearly melted, this new heat must have come from somewhere. Given that we are currently in an extended solar minimum, the sun does not appear to be the driver.
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Post by Andrew on Jan 6, 2013 11:29:16 GMT
Heat is obviously being added to the Arctic by solar irradiation of ice free Arctic water. This is new heat being added to the global climate system. Regardless of how such heat subsequently moves around, this new heat added to the Arctic Sea provides energy for warming. The ice insulates the warm water from cooling to space Obviously there is a competition between warming and cooling forces Importantly, a clear sunlit sky in winter does not obviously warm the ground that is exposed to the intense cold of the upper atmosphere compared to when exposed to the much warmer sub cloud temperatures and no sunshine. Most of the year the far north receives either very weak sunshine or no sunshine. Where are the studies on the impact of the various arctic features?
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Post by Andrew on Jan 6, 2013 11:47:31 GMT
Given that energy has been added to the Arctic Sea due to heat added to open Arctic water, the observed melting of Arctic Sea Ice, especially the loss of Arctic Sea Ice volume, indicates that a substantial amount of heat has recently entered the Arctic system. I agree, the physical processes that have directed these observed events have not been adequately described. In particular, the physical dynamics of heat transfer (as icefisher has said) are not clearly understood. The fundamental observation remains that the Arctic Sea is presently melting. Since it takes heat to melt ice, and ice has clearly melted, this new heat must have come from somewhere. Given that we are currently in an extended solar minimum, the sun does not appear to be the driver. A totally frozen arctic region would mean very little fresh water entered the sea and it would mean the ice melted more rapidly because it is warmed from below where the poles are an important cooling process on Earth However a warmer earth will mean more fresh water enters the Arctic and there will be more ability for a deeper protective fresh water ice forming layer to form There is therefore the basis of a very long term cycle Until we know at what point in time the ice began melting we are largely clueless as to what state it was hundreds or thousands of years ago What does seem obvious was that it was much thicker and more extensive around 1860. Concluding that the earth is receiving more heat based on Arctic melting is unscientific with our current state of knowledge
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Post by magellan on Jan 6, 2013 19:24:32 GMT
I have read the document Tstat linked to. If he read the section on the Bering Sea and Bering Strait, he would realize why I have been harping on the subject for the last two years and continue reminding him of the importance of the ice in that region. It is definitely not behaving as some Arctic "experts" claim it should be according to AGW "theory". The PDO appears to be firmly entrenched in deep negative territory, aka the "cycle" that typically lasts 20-30 years. The current Bering Sea ice anomaly which according to expert Mark Serreze said was a fluke in 2010. Thermostat says the Pacific and Atlantic are related to Arctic ice. Apparently he needs pictures to accompany graphical illustrations to better understand what is really taking place. The idea that Arctic is "adding heat to the system" thereby contributing to "global warming" is complete nonsense. It is the system that adds heat to the Arctic. There is no heat being added to the Pacific and Atlantic regions connected to the Arctic. Maybe our esteemed Dr. can explain the following graphs and picture and the fact there has been no global warming for 16+ years and a definite cooling trend for at least the last 10. Edit: had incorrect long on OHC
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Post by magellan on Jan 6, 2013 21:14:52 GMT
Disappearing Arctic ice not only causes heat waves in Russia, but also cold in China; that's what we're supposed to believe. Europe was supposed to turn into a tropical paradise. Now we're told less Arctic ice is causing more cold/snowy winters. The experts make it up as they go along. www.dw.de/record-chill-across-china-disrupts-transport/a-16500917
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Post by icefisher on Jan 7, 2013 1:24:36 GMT
Net loss for multiyear ice in a year would be surviving ice plus precipitation minus melt.
Thus one cannot just assume more heat has been recently entering the Arctic; it is only one possible explanation and its also the case there is no necessity for the heat to have been recently added if it is additional heat added to the arctic.
Tstat if you want to make these claims here you need to provide references. The reference about water exchanges you posted did not provide answers but instead laid out issues that need to be addressed and potential research that needs completion to actually estimate what you are jumping to a conclusion on.
.................Do you ever read any reference you post?
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Post by sigurdur on Jan 7, 2013 3:23:35 GMT
There is a lot about the Arctic Basin that is not understood.
This is highlighted by the paper that Tstat posted.
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Post by magellan on Jan 7, 2013 5:23:04 GMT
There is a lot about the Arctic Basin that is not understood. This is highlighted by the paper that Tstat posted. If tstat read it, he wouldn't have said the Arctic "adds heat" to the system. There isn't one mention of that in the paper, nor CO2, nor AGW. It is mostly an essay of postulating how the heat flows from and to the Arctic through the various water passages. A snippet referencing the Bering Strait: In addition, heat carried by Pacific inflow through Bering Strait appears to play an important, triggering role in recent sea ice decline in the western Arctic (Woodgate et al., 2010). So, then go to Woodgate et al 2010 ecco2.jpl.nasa.gov/data3/ATN_output/+temp/Woodgate_2010GRL.pdfTo illuminate the role of Pacific Waters in the 2007 Arctic sea-ice retreat, we use observational data to estimate Bering Strait volume and heat transports from 1991 to 2007. In 2007, both annual mean transport and temperatures are at record-length highs. Heat fluxes increase from 2001 to a 2007 maximum, 5–6 x 1020 J/yr. This is twice the 2001 heat flux, comparable to the annual shortwave radiative flux into the Chukchi Sea, and enough to melt 1/3rd of the 2007 seasonal Arctic sea-ice loss. We suggest the Bering Strait inflow influences sea-ice by providing a trigger for the onset of solar-driven melt, a conduit for oceanic heat into the Arctic, and (due to long transit times) a subsurface heat source within the Arctic in winter. The substantial interannual variability reflects temperature and transport changes, the latter (especially recently) being significantly affected by variability (> 0.2 Sv equivalent) in the Pacific-Arctic pressure-head driving the flow. ====================================================== Woodgate 2010 was also cited by a new paper: Solar irradiance modulation of Equator-to-Pole (Arctic) temperature gradients: Empirical evidence for climate variation on multi-decadal timescalesAbstract
Using thermometer-based air temperature records for the period 1850–2010, we present empirical evidence for a direct relationship between total solar irradiance (TSI) and the Equator-to-Pole (Arctic) surface temperature gradient (EPTG). Modulation of the EPTG by TSI is also shown to exist, in variable ways, for each of the four seasons. Interpretation of the positive relationship between the TSI and EPTG indices suggests that solar-forced changes in the EPTG may represent a hemispheric-scale relaxation response of the system to a reduced Equator-to-Pole temperature gradient, which occurs in response to an increasing gradient of incoming solar insolation. Physical bases for the TSI-EPTG relationship are discussed with respect to their connections with large-scale climate dynamics, especially a critical relationship with the total meridional poleward energy transport. Overall, evidence suggests that a net increase in the TSI, or in the projected solar insolation gradient which reflects any net increase in solar radiation, has caused an increase in both oceanic and atmospheric heat transport to the Arctic in the warm period since the 1970s, resulting in a reduced temperature gradient between the Equator and the Arctic. We suggest that this new interpretative framework, which involves the extrinsic modulation of the total meridional energy flux beyond the implicit assumptions of the Bjerknes Compensation rule, may lead to a better understanding of how global and regional climate has varied through the Holocene and even the Quaternary (the most recent 2.6 million years of Earth's history). Similarly, a reassessment is now required of the underlying mechanisms that may have governed the equable climate dynamics of the Eocene (35–55 million years ago) and late Cretaceous (65–100 million years ago), both of which were warm geological epochs. This newly discovered relationship between TSI and the EPTG represents the “missing link” that was implicit in the empirical relationship that Soon (2009) recently demonstrated to exist between multi-decadal TSI and Arctic and North Atlantic climatic change.
When the North Pacific cools, as is shown in the graphs I posted, what could one conclude? Again, this is the region Mark Serreze said was not going to continue cooling after 2010. Here it is 2013 and guess what. It is assumed the natural cycles in ocean processes are linear because CO2 has overpowered the oceans. That's it in a nutshell. My question to tstat, graywolf or anyone for that matter is, why are the North Pacific and North Atlantic cooling if the Arctic is supposedly heating up? Clearly, only the Central Arctic and Barent Sea is left in the Arctic doom drama. Virtually all waters surrounding them are freezing earlier and at higher extent than 5 years ago. sidads.colorado.edu/DATASETS/NOAA/G02186/plots/
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Post by thermostat on Jan 11, 2013 4:24:59 GMT
It is quite fascinating to see how the prominent forum members who participate in this thread respond to the observed Arctic Sea Ice melt from 2012.
As Sigurdur emphasized above. "There is a lot about the Arctic Basin that is not understood".
True dat! (just emphatically demonstrated!)
So let us return to fundamental evidence; ie the observation that the Arctic Sea Ice is melting.
Anyone here disagree that the Arctic Sea Ice is melting?
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Post by icefisher on Jan 11, 2013 5:25:52 GMT
It is quite fascinating to see how the prominent forum members who participate in this thread respond to the observed Arctic Sea Ice melt from 2012. As Sigurdur emphasized above. "There is a lot about the Arctic Basin that is not understood". True dat! (just emphatically demonstrated!) So let us return to fundamental evidence; ie the observation that the Arctic Sea Ice is melting. Anyone here disagree that the Arctic Sea Ice is melting? Ice is currently increasing. You will have to wait until March before you can say its melting again.
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Post by thermostat on Jan 11, 2013 5:48:34 GMT
It is quite fascinating to see how the prominent forum members who participate in this thread respond to the observed Arctic Sea Ice melt from 2012. As Sigurdur emphasized above. "There is a lot about the Arctic Basin that is not understood". True dat! (just emphatically demonstrated!) So let us return to fundamental evidence; ie the observation that the Arctic Sea Ice is melting. Anyone here disagree that the Arctic Sea Ice is melting? Ice is currently increasing. You will have to wait until March before you can say its melting again. icefisher, Sorry that you misunderstood me. When I wrote about the Arctic Sea Ice melting, I was talking about the ice melting over time. Obviously the ice increases in the winter, we get that.
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