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Post by thermostat on Jun 6, 2012 2:07:32 GMT
I note that WUWT is running a similar Arctic sea ice poll His readers have come up with a figure of 4.9, which has been submited to the ARCUS site This compares with 4.61 which was the September mean for 2011 i.e. +0.3 on 2011 For clarification Thermostat has already pointed out that:- "ARCUS actually uses the mean arctic sea ice extent (in million square kilometers) rather than the minimal extent. The monthly mean will be greater than the absolute minimum extent, so be aware to avoid confusion up front." Our poll refers to the absolute sea ice minimum which occurs in September For rough comparison with WUWT 4.63 would be +0.3 on the 2011 absolute minimum For the record WUWT readers overestimated the sea ice minimum last year by about 0.3 Anthony Watts asked his readers to be more cautious this year when cosidering their forcast Neilhamp, The ARCUS June numbers will be coming out soon. They generally post the initial projections around mid month. As you noted, the WUWT numbers here have historically been consistently high reflecting the intrinsic bias of that site. It can be expected that other ARCUS projections will be considerably lower. After giving it some thought, I have guessed 4.2 - 4.39; in specific guessing that 4.3 will be the number. As mentioned in previous posts, the winter pattern that pushed Ice to the Alaskan side and facilitated build up of relatively thick ice on that side of the Arctic Sea was balanced by widespread open water on the European side of the Arctic. Given that the ice in the Bering Sea was unusual this year, this is thin first year ice that will melt away shortly. The same can be said for seasonal ice around Canada (Hudson's Bay and Baffin Bay). Thus, this seasonal ice will not be a significant factor regarding the ultimate minimum. More importantly in the Arctic Sea itself, the relatively thin ice on the Siberian side, which was the consequence of the winter weather that pushed ice towards Alaska, is more vulnerable to melt this year and could also be adversely affected by persistent weather patterns such as occurred in 2007. Export via the Fram straight is also a concern here. Also, in addition, the reduction in albedo due to open water on the Atlantic side, the opening of substantial polynas around the Arctic Sea, and the early melting of snow cover on adjacent continental areas currently provide for an increased absorption of solar radiation over the next six weeks as the summer solstice occurs. This will add additional heat to the system compared with previous years. Importantly, at the same time, multi-year ice continues to be diminished (see the map in the April NSIDC post here, for example; nsidc.org/arcticseaicenews/2012/04/. It appears that 2012 is likely to follow the modern trend. A 4.3 million Sq. km minimum is a conservative estimate.
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Post by throttleup on Jun 6, 2012 12:32:58 GMT
Well, it's obvious the abnormally high Arctic temperatures are fueling this melt season.
Oh, wait...
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Post by thermostat on Jun 8, 2012 1:30:02 GMT
Well, it's obvious the abnormally high Arctic temperatures are fueling this melt season.
Oh, wait... The DMI Center for Ocean and Ice ocean.dmi.dk/arctic/meant80n.uk.phpprovides links to annual Arctic Temperature profiles for the past 54 years. Clicking through the years one will observe that summer temperatures do not change over this period where, in contrast, the Arctic Sea Ice has substantially changed. This is consistent with the physics involved in melting ice. The heat capacity of the atmosphere is far less than the heat capacity of water. It is the heat in the water that is important. How does heat enter the Arctic Sea system? Direct solar irradiation, which is affected by sea ice albeldo; ie more open water during the period of solar irradiation increasing the addition of heat to the system, is one factor. Run off from terrestrial sources also adds heat. Reduced snow cover and earlier melting of north flowing rivers are relevant factors. Also, ocean currents are important. The oceans have accumulated heat during the same time that the Arctic Sea Ice has diminished. It has been found that heat from the adjacent oceans is flowing into the Arctic Sea. Again, the physics is central. Water holds much more heat than air. It takes heat to melt ice. Arctic sea ice is melting. The heat is primarily coming from the water. Reduced albedo in the Arctic and increased heat within the ocean system are key factors.
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Post by thermostat on Jun 8, 2012 1:42:57 GMT
Interested observers will note by clicking through the years at the DMI Center for Ocean and Ice site ocean.dmi.dk/arctic/meant80n.uk.phpin contrast to summer temperatures which essentially do not change, autumn, winter and spring temperatures show substantial warming, especially in recent years. This warming has had the effect of reducing ice formation. Thus, the important feature of the temperature profile above is the conspicuous warm anamoly from day zero through day 100. The relatively elevated temperatures of the past winter resulted in reduced ice formation (physics again).
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Post by thermostat on Jun 8, 2012 2:25:15 GMT
Another important factor independent from temperature that affects the Arctic Sea Ice minumum is the export of arctic ice into warmer waters. The so-called 'dipole anamoly' is relevant here. The dipole anamoly is a weather pattern where high pressure persists off of Alaska and northwesten Canada, while low pressure resides off of Siberia. This weather pattern drives the Beaufort Gyre and Transpolar Drift, leading to sea ice export. The US Navy site provides a nice example of this weather pattern in their forecast for next week www7320.nrlssc.navy.mil/hycomARC/navo/arcticicespddrf/nowcast/icespddrf2012060618_2012061200_035_arcticicespddrf.001.gif
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Post by neilhamp on Jun 9, 2012 7:53:20 GMT
Hmm! 40% of poll now showing a minimum between 4.4 and 4.59 This suggests a return to 2008 or 2010 levels We shall have to wait and see. The likely result will become more clear towards the end of July
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Post by throttleup on Jun 9, 2012 23:54:26 GMT
Hmm! 40% of poll now showing a minimum between 4.4 and 4.59 This suggests a return to 2008 or 2010 levels We shall have to wait and see. The likely result will become more clear towards the end of July neilhamp, You are correct about having to wait and see. As the effervescent t'stat has succintly noted, there are many, many factors that affect sea ice area, extent and volume. Some of which actually have nothing to do with CO2, the evil, demon trace gas vital for life on this planet.
Always a hot topic though! Cheers.
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Post by sigurdur on Jun 10, 2012 0:25:53 GMT
When one looks at the climatic conditions of earth the last time that the Arctic was ice free during the summer, one can only pine for those conditions.
The Sahara desert was in bloom, the world was a lush green place.
With the increase in population, we will need more lush and bloom to feed them.
Tell me again......the downside to summer ice free Arctic?
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Post by thermostat on Jun 10, 2012 4:06:19 GMT
When one looks at the climatic conditions of earth the last time that the Arctic was ice free during the summer, one can only pine for those conditions. The Sahara desert was in bloom, the world was a lush green place. With the increase in population, we will need more lush and bloom to feed them. Tell me again......the downside to summer ice free Arctic? Placing Sigurdur's post into a scientific perspective: "History of sea ice in the Arctic" bprc.osu.edu/geo/publications/polyak_etal_seaice_QSR_10.pdfRegarding events of the past few years... "This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities." more completely Arctic sea-ice extent and volume are declining rapidly. Several studies project that the Arctic Ocean may become seasonally ice-free by the year 2040 or even earlier. Putting this into perspective requires information on the history of Arctic sea-ice conditions through the geologic past. This information can be provided by proxy records from the Arctic Ocean floor and from the surrounding coasts. Although existing records are far from complete, they indicate that sea ice became a feature of the Arctic by 47 Ma, following a pronounced decline in atmospheric pCO2 after the Paleocene–Eocene Thermal Optimum, and consistently covered at least part of the Arctic Ocean for no less than the last 13–14 million years. Ice was apparently most wide-spread during the last 2–3 million years in accordance with Earth’s overall cooler climate. Nevertheless, episodes of considerably reduced sea ice or even seasonally ice-free conditions occurred during warmer periods linked to orbital variations. The last low-ice event related to orbital forcing (high insolation) was in the early Holocene, after which the northern high latitudes cooled overall, with some superimposed shorter- term (multidecadal to millennial-scale) and lower-magnitude variability. The current reduction in Arctic ice cover started in the late 19th century, consistent with the rapidly warming climate, and became very pronounced over the last three decades. This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities.
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Post by magellan on Jun 10, 2012 4:53:34 GMT
When one looks at the climatic conditions of earth the last time that the Arctic was ice free during the summer, one can only pine for those conditions. The Sahara desert was in bloom, the world was a lush green place. With the increase in population, we will need more lush and bloom to feed them. Tell me again......the downside to summer ice free Arctic? Placing Sigurdur's post into a scientific perspective: "History of sea ice in the Arctic" bprc.osu.edu/geo/publications/polyak_etal_seaice_QSR_10.pdfRegarding events of the past few years... "This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities." more completely Arctic sea-ice extent and volume are declining rapidly. Several studies project that the Arctic Ocean may become seasonally ice-free by the year 2040 or even earlier. Putting this into perspective requires information on the history of Arctic sea-ice conditions through the geologic past. This information can be provided by proxy records from the Arctic Ocean floor and from the surrounding coasts. Although existing records are far from complete, they indicate that sea ice became a feature of the Arctic by 47 Ma, following a pronounced decline in atmospheric pCO2 after the Paleocene–Eocene Thermal Optimum, and consistently covered at least part of the Arctic Ocean for no less than the last 13–14 million years. Ice was apparently most wide-spread during the last 2–3 million years in accordance with Earth’s overall cooler climate. Nevertheless, episodes of considerably reduced sea ice or even seasonally ice-free conditions occurred during warmer periods linked to orbital variations. The last low-ice event related to orbital forcing (high insolation) was in the early Holocene, after which the northern high latitudes cooled overall, with some superimposed shorter- term (multidecadal to millennial-scale) and lower-magnitude variability. The current reduction in Arctic ice cover started in the late 19th century, consistent with the rapidly warming climate, and became very pronounced over the last three decades. This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities. They said the same damn things 80 years ago. Science is the belief in the ignorance of experts.
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Post by thermostat on Jun 10, 2012 5:13:08 GMT
Placing Sigurdur's post into a scientific perspective: "History of sea ice in the Arctic" bprc.osu.edu/geo/publications/polyak_etal_seaice_QSR_10.pdfRegarding events of the past few years... "This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities." more completely Arctic sea-ice extent and volume are declining rapidly. Several studies project that the Arctic Ocean may become seasonally ice-free by the year 2040 or even earlier. Putting this into perspective requires information on the history of Arctic sea-ice conditions through the geologic past. This information can be provided by proxy records from the Arctic Ocean floor and from the surrounding coasts. Although existing records are far from complete, they indicate that sea ice became a feature of the Arctic by 47 Ma, following a pronounced decline in atmospheric pCO2 after the Paleocene–Eocene Thermal Optimum, and consistently covered at least part of the Arctic Ocean for no less than the last 13–14 million years. Ice was apparently most wide-spread during the last 2–3 million years in accordance with Earth’s overall cooler climate. Nevertheless, episodes of considerably reduced sea ice or even seasonally ice-free conditions occurred during warmer periods linked to orbital variations. The last low-ice event related to orbital forcing (high insolation) was in the early Holocene, after which the northern high latitudes cooled overall, with some superimposed shorter- term (multidecadal to millennial-scale) and lower-magnitude variability. The current reduction in Arctic ice cover started in the late 19th century, consistent with the rapidly warming climate, and became very pronounced over the last three decades. This ice loss appears to be unmatched over at least the last few thousand years and unexplainable by any of the known natural variabilities. They said the same damn things 80 years ago. Science is the belief in the ignorance of experts. Magellan wrote "Science is the belief in the ignorance of experts" Magellan clearly does not have a clue about what science is.
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Post by magellan on Jun 10, 2012 5:21:47 GMT
They said the same damn things 80 years ago. Science is the belief in the ignorance of experts. Magellan wrote "Science is the belief in the ignorance of experts" Magellan clearly does not have a clue about what science is. Richard Feynman spoke those words. Do you know who he was?
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Post by thermostat on Jun 10, 2012 5:36:51 GMT
Why does it even matter what sort of dumb ass comments get posted on this forum anyway?
Most already have their minds made up, for ideological reasons.
Meantime, the earth is changing and science is learning. My posts are for the viewers who are curious and want to understand what is happening and how to understand it.
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Post by sigurdur on Jun 10, 2012 13:39:02 GMT
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Post by throttleup on Jun 11, 2012 11:45:02 GMT
Why does it even matter what sort of dumb ass comments get posted on this forum anyway? Most already have their minds made up, for ideological reasons. t'stat, As for your first point, quite correct. There are a lot of dumb ass comments on this board, and we appreciate your contribution.
Regarding your second point, a personal question if I may: Do you feel your mind is 'made up?'
I only ask due to the consistent theme of your contributions and your untoward reactions to individuals with a legitimate contrary viewpoint. And if your mind is made up, is it made up for 'ideological reasons' or 'other?' Sometimes it's difficult to tell the difference.
I think most people's minds are 'made up' to some extent. And that's a good thing. I mean, if you've read material or spoken to people or exposed yourself to information and have come to a 'conclusion' as a result, that seems to be the usual path people follow as they try to make sense of the world around them. But if they have a desire to learn and know what is true and right, they will generally continue to take in new information, process it, and adjust their position accordingly. If one understands that even the 'experts' can be wrong -- can make mistakes -- (the examples one could list are legion) -- then one can keep learning.
Others, as you well know, consider their insight and information to be superior to others and will make dumb ass comments as a result.
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