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Politics : Stockman Scott's Political Debate Porch -- Ignore unavailable to you. Want to Upgrade?


To: T L Comiskey who wrote (86243)1/23/2012 1:00:03 PM
From: longnshort2 Recommendations  Respond to of 89467
 
“We Live In The Coldest Period Of The Last 10.000 Years"
January 22, 2012

tags: Greenland, Holocene

By Paul Homewood



Jørgen Peder Steffensen is an Associate Professor at the University of Copenhagen and one of the world’s leading experts on ice cores. Using ice cores from sites in Greenland, he has been able to reconstruct temperatures there for the last 10000 years. So what are his conclusions?

  • Temperatures in Greenland were about 1.5 C warmer 1000 years ago than now.
  • It was perhaps 2.5 C warmer 4000 years ago.
  • The period around 1875, at the lowest point of the Little Ice Age, marked the coldest point in the last 10,000 years.
  • Other evidence from elsewhere in the Northern Hemisphere confirms this picture.
His final comment is particularly telling :-

I agree totally we have had a global temperature increase in the 20thC – but an increase from what? ..Probably an increase from the lowest point in the last 10,000 years.

We started to observe meteorology at the coldest point in the last 10,000 years.

Have a look at this short video of Professor Steffensen’s here.

The Professor’s findings are supported by other research such as this study.

http://notalotofpeopleknowthat.wordpress.com/2012/01/22/we-live-in-the-coldest-period-of-the-last-10-000-years/



To: T L Comiskey who wrote (86243)1/23/2012 1:00:43 PM
From: longnshort  Respond to of 89467
 
Little Ice Age Coldest Period In The Last 7000 Years In Greenland
January 21, 2012

tags: Greenland, Holocene, Little Ice Age, mwp

By Paul Homewood

A paper published last year “ Climate variability in West Greenland during the last 1500 years” by Ribeiro et al attempted to map temperature changes in Disko Bay, in West Greenland, during the last 1500 years by analysing marine sediments. Their conclusions included :-

  • The past 1500 years have been identified as one of the coldest intervals of the last 7000 years in Disko Bay.
  • This period is inserted in the context of the Neoglacial Advance of the Greenland Ice Sheet starting at c. 5000 years BP and culminating in the Little Ice Age (e.g. Kelly et al 1980).
  • A long term cooling trend from the mid-late-holocene is consistent with air temperature reconstructions from Greenland ice core data (Vinther et al 2009,2010). ……..
  • …… And with climate studies in areas influenced by the East Greenland Current (e.g. Jennings et al 2002; Moros et al 2006).
  • This late Holocene cooling trend is also consistent with marine and terrestrial records from several locations in the Northern Hemisphere (e.g. Levac et al 2001; Moros et al 2004).
  • The dinoflagellate cyst record Disko Bay revealed generally cold sea surface conditions and extensive sea ice throughout the entire studied period.


As well as putting the last 1500 years into long term perspective, the authors have found that their analysis confirms a warmer period between 1050 and 1250 AD and extensive sea ice conditions from 1500 AD. In particular they make this interesting comment :-

Presently, the Baffin Bay southern sea-ice boundary extends from Disko Island to the southwest, towards Canada. This would imply that prior to AD 1250 this boundary was more northerly and gradually moved towards the vicinity of the core site until after AD 1500 (Little Ice Age), when it was positioned south of the core site.

In other words, sea ice was less extensive in the MWP than now.

We therefore appear, as far as Greenland is concerned at any rate, to be going through a slightly warmer interlude within a much longer cooling period. Maybe we should be worrying that the next LIA will be colder still.

http://notalotofpeopleknowthat.wordpress.com/2012/01/21/little-ice-age-coldest-period-in-the-last-7000-years-in-greenland/



To: T L Comiskey who wrote (86243)1/23/2012 1:01:06 PM
From: longnshort  Respond to of 89467
 
Briffa Confirms MWP In Southern Hemisphere
December 26, 2011

tags: climategate

From the Climategate collection, a revealing email from Keith Briffa to Jonathan Overpeck, which makes suggested changes to one of Overpeck’s papers.

date: Wed Feb 15 16:43:41 2006
from: Keith Briffa <REDACTED>
subject: bullets
to: REDACTED
Peck
do not think you will like what I say here , but I am going to give straight answers to
your questions.

3) I suggest this should be taken together , the sparse evidence of Southern Hemisphere temperatures prior to the period of instrumental records indicates that overall warming has occurred during the last
350 years, but the even fewer longer regional records indicate earlier periods that are as warm, or warmer than, 20th century means.

Mann’s Hockey Stick has always relied on the claim that the undoubted warmth in Northerly latitudes during the MWP was offset by a cooler climate elsewhere. Briffa is clear that what little data there is in the Southern Hemisphere says the opposite.

This raises two questions :-

1) Why did Mann come to the conclusion he did when the evidence pointed in the opposite direction?

2) Did Overpeck alter his paper to reflect Briffa’s criticisms?

The link to email 4871 is here.
notalotofpeopleknowthat.wordpress.com