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Post by sigurdur on Oct 16, 2010 1:31:36 GMT
It would depend on what time period you are referring to thermostat. Early Holocen? Mid Holocene?
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Post by thermostat on Oct 16, 2010 1:50:03 GMT
It would depend on what time period you are referring to thermostat. Early Holocen? Mid Holocene? Sigurdur, Early Holocene vs Mid Holoene? I'm not clear what your comment is. Could you clarify?
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Post by sigurdur on Oct 16, 2010 2:23:14 GMT
There are numerous papers published that show that the mid holocene arctic was ice free. One of the latest concerns the beaches on north Greenland. The wave action on those beaches could only have occured if the Arctic was virtually ice free. Hence, when you say recent...please define. An ice free Arctic has happened during the Holocene.
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Post by thermostat on Oct 16, 2010 2:42:10 GMT
There are numerous papers published that show that the mid holocene arctic was ice free. One of the latest concerns the beaches on north Greenland. The wave action on those beaches could only have occured if the Arctic was virtually ice free. Hence, when you say recent...please define. An ice free Arctic has happened during the Holocene. Sigurdur, Yes, there is good evidence that this and that place in the arctic was ice free during the Holocene Thermal Maximum. Evidence indicates that there was a time 10K to 5K years ago when various places saw substantial melting. The precise place changes over time. Recently? the past several thousand years. Evidence indicates, 'not so much' evidence of arctic melting/rather the opposite; cooling.
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Post by magellan on Oct 16, 2010 2:55:31 GMT
There are numerous papers published that show that the mid holocene arctic was ice free. One of the latest concerns the beaches on north Greenland. The wave action on those beaches could only have occured if the Arctic was virtually ice free. Hence, when you say recent...please define. An ice free Arctic has happened during the Holocene. Sigurdur, Yes, there is good evidence that this and that place in the arctic was ice free during the Holocene Thermal Maximum. Evidence indicates that there was a time 10K to 5K years ago when various places saw substantial melting. The precise place changes over time. Recently? the past several thousand years. Evidence indicates, 'not so much' evidence of arctic melting/rather the opposite; cooling. Bravo! Excellent rendition of circular reasoning.
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Post by thermostat on Oct 16, 2010 3:07:15 GMT
Sigurdur, Yes, there is good evidence that this and that place in the arctic was ice free during the Holocene Thermal Maximum. Evidence indicates that there was a time 10K to 5K years ago when various places saw substantial melting. The precise place changes over time. Recently? the past several thousand years. Evidence indicates, 'not so much' evidence of arctic melting/rather the opposite; cooling. Bravo! Excellent rendition of circular reasoning. Magellan, Can you then say the arctic was previously as warm it is today? And can you povide some data to support your assertions? When was this Magellan?
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Post by magellan on Oct 16, 2010 3:20:09 GMT
Bravo! Excellent rendition of circular reasoning. Magellan, Can you then say the arctic was previously as warm it is today? And can you povide some data to support your assertions? When was this Magellan? A few threads back you said there was no evidence for Arctic climate cycles. Let us know when the forests start reappearing ok? www.geog.ucla.edu/downloads/634/269.pdfI have many others. While you're at it, check and see how far north into the Arctic your sailboat hero made it compared to 1922 docs.lib.noaa.gov/rescue/mwr/050/mwr-050-11-0589a.pdf
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Post by thermostat on Oct 16, 2010 3:24:00 GMT
Magellan, Can you then say the arctic was previously as warm it is today? And can you povide some data to support your assertions? When was this Magellan? A few threads back you said there was no evidence for Arctic climate cycles. Let us know when the forests start reappearing ok? www.geog.ucla.edu/downloads/634/269.pdfI have many others. Magellan, Be sure to let forum members know when you come up with something of some actual substance.
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Post by flyingmonkey on Oct 16, 2010 4:20:11 GMT
They did. Most recently in 1944... the NW passage portion, anyway. The 2010 Norwegians are further south than the 1944 Norwegian , after reading the St Roch log, and skimming these 2010 sailors blog. ( St Roch captain , Henry Larsen was born in Norway in 1899 but took Canadian citizenship in 1924) RCMP Sgt. Henry Larsen's transit ; 7,295 miles Halifax to Vancouver via the northern NW passage route in 86 days, when the St Roch was rigged as a schooner-arrived in Vancouver Oct 16 1944. I was aboard the ship this June in the Vancouver maritime museum, and read the log-quite interesting. First vessel to complete the Northwest Passage in one season (1944), first to use the more northerly, deeper route and to complete the Passage in both directions. In 1944 on the Russian /Norwegian side,( the Russian Northern Route ) we hadn't sunk the German Battleships ( Tirpitz, Scheer and Hipper ) in the Norwegian Fjords yet, and the Nazi submarine wolf packs were more worrisome than ice. en.wikipedia.org/wiki/Convoy_PQ_17 The Northern route refroze pretty hard in a bitterly cold 1946 , according to a senior Russian naval officer ( I mislaid the link )-although Stalin didn't abandon the route-first transited in a single season in 1934; the Russian ships sailing the route ceased almost entirely in '93 or so, mainly for lack of funds following the break up of the Soviet Union. It looks like these these Viking fellows did it 800 years ago, if you scroll down to map 2C www.spirasolaris.ca/1aintro.htmlwww.amazon.com/Viking-America-Norse-Crossings-Legacy/dp/0385025858www.spirasolaris.ca/sbb4g1bv.html " ..As the twelfth century ended, the climate reversed. Ice crept southward, all over Europe snow fell lower on the mountain slopes, upland trees died. Pack-ice cluttered the coasts of Greenland, then tightened an Arctic noose to strangle movement. Moreover, in describing recent research carried out at an Inuit site on the Burnside River south of the Kent Peninsula, Bryan Gordon of the Museum of Civilization (Nadlok and the Origin of the Copper Inuit - Climate, Dating and Seasonality) provides data that suggest the Passage may have become difficult if not impractical by 1450 A.D: ...Nadlok's carbon-dated floors and levels show a 1450-1750 A.D. occupation in the Little Ice Age, a time of deteriorating climate when ocean temperature fell 1-3 deg. C and the Arctic summer front retreated 4-5 deg. of latitude. Sea ice stayed all year in sheltered Bathurst Inlet and east Coronation Gulf, inevitably disrupting sea-mammals and their hunters, but with little effect on caribou...." flyingmonkey You will be cheered to hear that the crew of the Northern Passage completed their circumnavgation of the arctic sea yesterday, when they crossed their wake and arrived back in Norway. www.ousland.no/2010/10/we%e2%80%99ve-crossed-our-wake-%e2%80%93-and-arrived-in-norway/This appears to be the first time in recorded human history that anyone has circumnavigated the arctic in a single season. (Implications for this discussion forum are obvious) There are many historical records describing the frozen conditions in the arctic and difficulties in navigation there. Are you claiming that conditions this year were nothing unusual? In this age of instant and massive communication, a publicity stunt is not unusual. There is at least one a week. Maybe he is a brave explorer, and people that believe human-expelled carbon is melting the arctic are abusing his feat of endurance-pointing at his achievement as somehow a verification of their belief structure. I think, from what little I skimmed on his blog, that the writing style may aid this end ( "dramatic ice loss, never before ' [or whatever words to that effect are used there].. “....The changes that we are witnessing will influence climate on a global scale, in addition to the whole range of animal life in the Arctic – especially seals and polar bears, whose lives are dependent on the sea ice. It is our hope that our voyage will be seen as a strong, visible symbol of the scale and the speed of these changes....” etc ) ...or it may just be coincident. I know that he went through the southern route of the passage, ( Amundsen gulf, Dolphin and Union strait ..Cambridge bay,...etc... which is on the south end of Victoria island ) and that the ST Roch in 1944 went through the more often blocked Prince of Wales strait , Viscount Melville sound..etc... We know that the 1944 route that the St Roch took re-froze for decades-for one entire pdo cycle, which may be only a partial reason it did so ( 40,000 hp steel hulled ice breakers , e.g 1969 Manhattan, Canadian breakers in other subsequent decades etc . ) couldn't get through that ( 1944 St Roch ) same route until our most recent decade. So , specifically, his journey was not 'unusual '-if by unusual you mean 'there never was that little ice there ever , provable by his path'. What do you think caused the ice to retreat so significantly in 1944 that RCMP Sgt. Henry Larsen , on completing the first transit in both directions wrote in the ships log “ the northwest passage is open for sailing by wooden ships “ ? What evidence do you have that that 1944 natural causative agent (s) , whatever they were/are , has now vanished? What evidence is there that that natural climatic variation that existed 1500 years ago, which allowed a freedom loving people to flee iceland and settle Greenland -can never ( and hasn't )returned? We do have their european metal knives and boat rivets , substantially farther north than these adventurous and I think somewhat alarmist 2010 Norwegian/Europeans . I would disagree with your statements that this has never been done ( say, in human history ) -unless you are only claiming that there is no written record of it-an insignificant claim given the fragile lifespan of three centuries of oral tradition followed by further centuries of only slightly less fragile parchment, Inventio fortunata and Gerard Mercator notwithstanding. As opposed to say, the ' written word ' of several century old boat rivets which have been found in the high arctic. I would say that the 2010 Norwegians , having had several centuries longer of boat building engineering experience than the builders of earlier vessels-most probably are using a Kevlar /composite hull, ( it might be fiberglass,-I didn't try to find out what this 2010 arctic sailing ship is made of ) which would be much stronger than say, the inverted skin-covered technology and lesser strength to weight ratios subsumed within the Lief Erikson era . So, the 2010 vessel is much stronger, than older vessels. en.wikipedia.org/wiki/Specific_strength
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Post by thermostat on Oct 16, 2010 4:26:59 GMT
flyingmonkey You will be cheered to hear that the crew of the Northern Passage completed their circumnavgation of the arctic sea yesterday, when they crossed their wake and arrived back in Norway. www.ousland.no/2010/10/we%e2%80%99ve-crossed-our-wake-%e2%80%93-and-arrived-in-norway/This appears to be the first time in recorded human history that anyone has circumnavigated the arctic in a single season. (Implications for this discussion forum are obvious) There are many historical records describing the frozen conditions in the arctic and difficulties in navigation there. Are you claiming that conditions this year were nothing unusual? In this age of instant and massive communication, a publicity stunt is not unusual. There is at least one a week. Maybe he is a brave explorer, and people that believe human-expelled carbon is melting the arctic are abusing his feat of endurance-pointing at his achievement as somehow a verification of their belief structure. I think, from what little I skimmed on his blog, that the writing style may aid this end ( "dramatic ice loss, never before ' [or whatever words to that effect are used there].. “....The changes that we are witnessing will influence climate on a global scale, in addition to the whole range of animal life in the Arctic – especially seals and polar bears, whose lives are dependent on the sea ice. It is our hope that our voyage will be seen as a strong, visible symbol of the scale and the speed of these changes....” etc ) ...or it may just be coincident. I know that he went through the southern route of the passage, ( Amundsen gulf, Dolphin and Union strait ..Cambridge bay,...etc... which is on the south end of Victoria island ) and that the ST Roch in 1944 went through the more often blocked Prince of Wales strait , Viscount Melville sound..etc... We know that the 1944 route that the St Roch took re-froze for decades-for one entire pdo cycle, which may be only a partial reason it did so ( 40,000 hp steel hulled ice breakers , e.g 1969 Manhattan, Canadian breakers in other subsequent decades etc . ) couldn't get through that ( 1944 St Roch ) same route until our most recent decade. So , specifically, his journey was not 'unusual '-if by unusual you mean 'there never was that little ice there ever , provable by his path'. What do you think caused the ice to retreat so significantly in 1944 that RCMP Sgt. Henry Larsen , on completing the first transit in both directions wrote in the ships log “ the northwest passage is open for sailing by wooden ships “ ? What evidence do you have that that 1944 natural causative agent (s) , whatever they were/are , has now vanished? What evidence is there that that natural climatic variation that existed 1500 years ago, which allowed a freedom loving people to flee iceland and settle Greenland -can never ( and hasn't )returned? We do have their european metal knives and boat rivets , substantially farther north than these adventurous and I think somewhat alarmist 2010 Norwegian/Europeans . I would disagree with your statements that this has never been done ( say, in human history ) -unless you are only claiming that there is no written record of it-an insignificant claim given the fragile lifespan of three centuries of oral tradition followed by further centuries of only slightly less fragile parchment, Inventio fortunata and Gerard Mercator notwithstanding. As opposed to say, the ' written word ' of several century old boat rivets which have been found in the high arctic. I would say that the 2010 Norwegians , having had several centuries longer of boat building engineering experience than the builders of earlier vessels-most probably are using a Kevlar /composite hull, ( it might be fiberglass,-I didn't try to find out what this 2010 arctic sailing ship is made of ) which would be much stronger than say, the inverted skin-covered technology and lesser strength to weight ratios subsumed within the Lief Erikson era . So, the 2010 vessel is much stronger, than older vessels. en.wikipedia.org/wiki/Specific_strengthflyingmomkey I don't think it is a question that today's technology is superior to yesterday's. I think the question is about today's weather vs yesterdays. That is, the arctic sea ice over time.
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Post by flyingmonkey on Oct 16, 2010 4:42:17 GMT
In this age of instant and massive communication, a publicity stunt is not unusual. There is at least one a week. Maybe he is a brave explorer, and people that believe human-expelled carbon is melting the arctic are abusing his feat of endurance-pointing at his achievement as somehow a verification of their belief structure. I think, from what little I skimmed on his blog, that the writing style may aid this end ( "dramatic ice loss, never before ' [or whatever words to that effect are used there].. “....The changes that we are witnessing will influence climate on a global scale, in addition to the whole range of animal life in the Arctic – especially seals and polar bears, whose lives are dependent on the sea ice. It is our hope that our voyage will be seen as a strong, visible symbol of the scale and the speed of these changes....” etc ) ...or it may just be coincident. I know that he went through the southern route of the passage, ( Amundsen gulf, Dolphin and Union strait ..Cambridge bay,...etc... which is on the south end of Victoria island ) and that the ST Roch in 1944 went through the more often blocked Prince of Wales strait , Viscount Melville sound..etc... We know that the 1944 route that the St Roch took re-froze for decades-for one entire pdo cycle, which may be only a partial reason it did so ( 40,000 hp steel hulled ice breakers , e.g 1969 Manhattan, Canadian breakers in other subsequent decades etc . ) couldn't get through that ( 1944 St Roch ) same route until our most recent decade. So , specifically, his journey was not 'unusual '-if by unusual you mean 'there never was that little ice there ever , provable by his path'. What do you think caused the ice to retreat so significantly in 1944 that RCMP Sgt. Henry Larsen , on completing the first transit in both directions wrote in the ships log “ the northwest passage is open for sailing by wooden ships “ ? What evidence do you have that that 1944 natural causative agent (s) , whatever they were/are , has now vanished? What evidence is there that that natural climatic variation that existed 1500 years ago, which allowed a freedom loving people to flee iceland and settle Greenland -can never ( and hasn't )returned? We do have their european metal knives and boat rivets , substantially farther north than these adventurous and I think somewhat alarmist 2010 Norwegian/Europeans . I would disagree with your statements that this has never been done ( say, in human history ) -unless you are only claiming that there is no written record of it-an insignificant claim given the fragile lifespan of three centuries of oral tradition followed by further centuries of only slightly less fragile parchment, Inventio fortunata and Gerard Mercator notwithstanding. As opposed to say, the ' written word ' of several century old boat rivets which have been found in the high arctic. I would say that the 2010 Norwegians , having had several centuries longer of boat building engineering experience than the builders of earlier vessels-most probably are using a Kevlar /composite hull, ( it might be fiberglass,-I didn't try to find out what this 2010 arctic sailing ship is made of ) which would be much stronger than say, the inverted skin-covered technology and lesser strength to weight ratios subsumed within the Lief Erikson era . So, the 2010 vessel is much stronger, than older vessels. en.wikipedia.org/wiki/Specific_strengthflyingmomkey I don't think it is a question that today's technology is superior to yesterday's. I think the question is about today's weather vs yesterdays. That is, the arctic sea ice over time. Indeed. Although The question that you typed, and that I answered to the best of my ability , without spending much time on it, was about a boats strength, and modern technology. You can see your question right there. (: " Modern technology has also been an issue here. The Northern Passage is a fragile vessel; not the sort of craft that would fair well if it was banging into chunks of ice. As you expound on recent historical navigations of the arctic I would be curious about your insights regarding how such a physically fragile vessel could have possibly sailed such waters in the past." Then I disagreed with you that the vessel was (comparatively , as you alleged ) fragile-and now we even all have a useful strength to weight ratio table to look at-which was my 'insight' part.. (:
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Post by kiwistonewall on Oct 16, 2010 21:26:20 GMT
Saw a BBC doco on the Fram & Nansen last night. Makes modern polar explorers look like wimps, though they use a lot of the ideas pioneered by Nansen. Norwegians can be proud.
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