Post by marchesarosa on Sept 3, 2010 23:03:55 GMT
ROMAN WARM PERIOD Con’td.
Let's just reassemble this debate, if we can, after so many strange deletions wrecked other threads that covered this ground on the old BBC Science Board.
I think it was lazarus who disputed the existence of the Roman Warm Period 200 BC to 400 AD when North Africa was the granary of the Empire and the land which is now so arid was much more fertile due to higher rainfall.
We were wondering whether warmer climate epochs tend to be wetter ones. I argued they were and that the Roman Warm Period with a much more fertile North Africa was a good example.
I quoted an article by David Whitehouse called "New technique shows Roman Warm Period Warmer than Present Day" which appeared here
sppiblog.org/news/new-technique-shows-roman-warm-period-warmer-than-present-day
He was discussing the research paper called
"Two millennia of North Atlantic seasonality
and implications for Norse colonies"
by William P. Pattersona,1, Kristin A. Dietricha, Chris Holmdena, and John T. Andrewsb
www.pnas.org/content/early/2010/03/02/0902522107.full.pdf
This is a fascinating piece of research in which the layers of the shells of certain molluscs have been found to contain a chemical signal from which the temperature at the location they were found may be inferred.
This is obviously extremely relevant to dendro-palaeo-climatologists who have been messing around with treemometers to do ancient temperature reconstructions for far too long and wasting a lot of public money, too.
The shell research could be useful, if it proved effective, in settling the climatology dispute over whether the much hyped late 20th century temperatures attributed to to higher CO2 were really "unprecedented" after all.
This is why such research is so valuable and why some "warmists" don't want to see it discussed in forums like this.
Princess Anne remarked
The answer to that, princess, is that the shells are not "global" proxies at all, they are proxies for the past temperatures of the places they are found.
Since they display a uniform chemical signal that correlates with temperature when the molluscs were alive they offer a very easy and reliable means of establishing historical temperatures round the world because they are found everywhere and are relatively easy to access.
The problem with the hockeystick "multi-proxy" studies (with which you may be confusing this new shell proxy) was that many DIFFERENT types of proxy from round the world were mysteriously "averaged out" by Michael Mann and his many co-authors, to try to create a "global mean temperature".
That has been demonstrated to be a futile and flawed exercise several times. How so-called climate "scientists" have been able to avert their eyes from this travesty for so long defies comprehension.
But now the mollusc shells seem to offer a more rational way to estimate historic temperatures. Good.
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Let's just reassemble this debate, if we can, after so many strange deletions wrecked other threads that covered this ground on the old BBC Science Board.
I think it was lazarus who disputed the existence of the Roman Warm Period 200 BC to 400 AD when North Africa was the granary of the Empire and the land which is now so arid was much more fertile due to higher rainfall.
We were wondering whether warmer climate epochs tend to be wetter ones. I argued they were and that the Roman Warm Period with a much more fertile North Africa was a good example.
I quoted an article by David Whitehouse called "New technique shows Roman Warm Period Warmer than Present Day" which appeared here
sppiblog.org/news/new-technique-shows-roman-warm-period-warmer-than-present-day
He was discussing the research paper called
"Two millennia of North Atlantic seasonality
and implications for Norse colonies"
by William P. Pattersona,1, Kristin A. Dietricha, Chris Holmdena, and John T. Andrewsb
www.pnas.org/content/early/2010/03/02/0902522107.full.pdf
This is a fascinating piece of research in which the layers of the shells of certain molluscs have been found to contain a chemical signal from which the temperature at the location they were found may be inferred.
This is obviously extremely relevant to dendro-palaeo-climatologists who have been messing around with treemometers to do ancient temperature reconstructions for far too long and wasting a lot of public money, too.
The shell research could be useful, if it proved effective, in settling the climatology dispute over whether the much hyped late 20th century temperatures attributed to to higher CO2 were really "unprecedented" after all.
This is why such research is so valuable and why some "warmists" don't want to see it discussed in forums like this.
Princess Anne remarked
But you do recognize ancient shells as a good proxy for global temperatures, because, surprise they fit in with your skeptical theory of global warming. And the shells may not be quite as ubiquitous (through time) as you previously stated, most seem to convert to fossils.
The answer to that, princess, is that the shells are not "global" proxies at all, they are proxies for the past temperatures of the places they are found.
Since they display a uniform chemical signal that correlates with temperature when the molluscs were alive they offer a very easy and reliable means of establishing historical temperatures round the world because they are found everywhere and are relatively easy to access.
The problem with the hockeystick "multi-proxy" studies (with which you may be confusing this new shell proxy) was that many DIFFERENT types of proxy from round the world were mysteriously "averaged out" by Michael Mann and his many co-authors, to try to create a "global mean temperature".
That has been demonstrated to be a futile and flawed exercise several times. How so-called climate "scientists" have been able to avert their eyes from this travesty for so long defies comprehension.
But now the mollusc shells seem to offer a more rational way to estimate historic temperatures. Good.
000000000