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Post by Ratty on Jan 11, 2015 11:52:43 GMT
"both the Medieval Warm Period (MWP) and Little Ice Age (LIA) were cooler than the present (AD 1961–1990)."
Is that good news for sceptics?
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Post by douglavers on Jan 11, 2015 12:07:03 GMT
It is strange that the Vikings were able to colonise Greenland if the climate was cooler in the MWP. Their graves are locked in permafrost.
Also, the English must have had a very hardy variety of grapes to grow them all over England. These days there are a few struggling producers near the South Coast.
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Post by graywolf on Jan 11, 2015 12:15:54 GMT
A bunch of renegades ( with a price on their heads and boats full of slaves) trying to find their own 'box canyon' to hide in is no measure of climate? What is is the fact they tried to push on further to find better conditions ( Vineland expedition).
Things got so tough they did the worst thing possible and used their only means of escape to survive the last winters ( and burned their boats) leaving them at the mercy of conditions there ( only scrub ,dwarf shrubs to burn).
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Post by acidohm on Jan 11, 2015 13:00:34 GMT
I got chastised for bringing up agriculture in Greenland 1000 years ago...to be fair this chap is from Iceland and seems to know more about it.....
----Acidohm, temperature in Iceland and Greenland was about the same 1000 years ago as it is now. Not warmer, neither colder. Just about the same, at least judged by glacier advance. I know the data.
In Skaftafell national park in Iceland, you can see the data for yourself. 1000 years ago, climate was just about the same.
Regarding 1000 years ago “farms”, the vikings were growing grains (barley) like we do it nowadays, but during the little ice age, and for many centuries, grain growing was impossible in Iceland, up until this last century. Wheat (which is less cold-tolerant than barley) was never grown during the viking time, but it is nowadays. The situation in Greenland was identical to Iceland.
Please dont just say things you read somewhere, things which are not fully incorrect.
In the Alps (at least in Austria) however the situation is different. The climate was still colder 1000 years ago than nowadays (or at least glaciers were more advanced than nowadays), but some 4000 years ago the climate was, yes, significantly warmer, with trees growing where now is melting glacier.----
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Post by sigurdur on Jan 11, 2015 15:41:24 GMT
"both the Medieval Warm Period (MWP) and Little Ice Age (LIA) were cooler than the present (AD 1961–1990)." Is that good news for sceptics? I actually called the author of this paper, questioning his methodology. It appears the methodology was ok, but the resolution is not monthly. Also to note, things he told me privately, that the error ranges of the pollen etc are wide enough that temps "could" have been higher during the MWP. Using error bars, this also indicates temps "could" have been colder. I was more interested in the hydrology than the temps. Unless we have a Bond event or a DO event, temps will stay within a certain parameter. It is rainfall that seems to change. Even long ago, there was an exhibited 160 year cycle in the hydrology. I don't know if there is a sun cycle that is 160 years or not. What has been determined is that there is a most deff 160 year hydrological cycle in the center of the North American continent. Presently where I live, we are near the apex of that wet phase of the 160 year cycle. 80 wet years, followed by 80 dry years. Devils Lake is full, which is an indicator of the apex of the wet cycle. Also, some of the authors "grow lines" (zones) were a little off. He acknowledged this, but said it wasn't important to the paper. He had taken the grow lines from another paper.
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Post by sigurdur on Jan 11, 2015 15:45:40 GMT
"I got chastised for bringing up agriculture in Greenland 1000 years ago...to be fair this chap is from Iceland and seems to know more about it.....
----Acidohm, temperature in Iceland and Greenland was about the same 1000 years ago as it is now. Not warmer, neither colder. Just about the same, at least judged by glacier advance. I know the data."
I am of Icelandic decent, and agree with that this chap told you Acidohm. I will also state that the LIA time frame was brutal in Iceland. At the tale end there was famine, lack of fish etc. That was the main driver for the out migration of Icelanders to the USA. Most of them initially settled near Gimili, Manitoba. That is a town on Lake Winnipeg. Lake Winnipeg is an excellent fishery, and the landscape is similar to Icelands. I have boatloads of cousins who still reside in that area, and us local folks make trips to see them at times. There is also a Provincial Park called Hecla where many Icelanders settled as well.
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Post by acidohm on Jan 11, 2015 15:49:40 GMT
Named after one of icelands larger volcanos! That very interesting background info....thx sigurdur! ?
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Post by sigurdur on Jan 11, 2015 15:51:57 GMT
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Post by Ratty on Jan 11, 2015 22:34:54 GMT
Of course.
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Post by sigurdur on Jan 11, 2015 23:55:36 GMT
Of course. Good catch Ratty....
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Post by douglavers on Jan 12, 2015 6:52:08 GMT
["---Acidohm, temperature in Iceland and Greenland was about the same 1000 years ago as it is now. Not warmer, neither colder. Just about the same, at least judged by glacier advance. I know the data."] Subsequently in the 11th & 12th and first half 13th Century [MWP] it was warmer. I think it is those graves which are now in permafrost. Hence it was warmer than now in Greenland. Climate became much colder mid 13th Century, and Greenland Vikings died out in the 15th Century. archive.archaeology.org/online/features/greenland/
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Post by nonentropic on Jan 12, 2015 10:30:48 GMT
A lot of this stuff is hard to quantify.
Even glacial terminus points are as affected by snow accumulation as temperature. We witness that here in NZ and other regions.
Those graves could have been dug in the reported warm summers of the cold periods its just not that definitive.
pollen blows a long way and tree rings are a good example of proxy delusion warm weather appears to resemble wet periods.
All a long time ago.
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Post by missouriboy on Jan 12, 2015 18:16:48 GMT
Thank you Sig! Some anonymously wet years in Georgia and the Carolinas during a part of the Little Ice Age with no direct indication of what was happening in the Midwest...maybe dry, maybe not. I'll expand my search.
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Post by acidohm on Jan 12, 2015 19:29:29 GMT
["---Acidohm, temperature in Iceland and Greenland was about the same 1000 years ago as it is now. Not warmer, neither colder. Just about the same, at least judged by glacier advance. I know the data."] Subsequently in the 11th & 12th and first half 13th Century [MWP] it was warmer. I think it is those graves which are now in permafrost. Hence it was warmer than now in Greenland. Climate became much colder mid 13th Century, and Greenland Vikings died out in the 15th Century. archive.archaeology.org/online/features/greenland/Fascinating read! Thx douglavers.
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Post by Ratty on Jan 12, 2015 23:51:34 GMT
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