Thirty-Five Years of Climate Change in Antarctica
John
http://www.co2science.org/journal/2002/v5n5c1.htm
Thirty-Five Years of Climate Change in Antarctica
Reference
Doran, P.T., Priscu, J.C., Lyons, W.B., Walsh, J.E., Fountain, A.G.,
McKnight, D.M., Moorhead, D.L., Virginia, R.A., Wall, D.H., Clow, G.D.,
Fritsen, C.H., McKay, C.P. and Parsons, A.N. 2002. Antarctic climate
cooling and terrestrial ecosystem response. Nature advance online
publication, 13 January 2002 (DOI 10.1038/nature710).
What was done
Between 1986 and 2000, the authors measured a number of meteorological
parameters in the McMurdo Dry Valleys of Antarctica, while they
simultaneously measured various characteristics of the region's indigenous
life forms. They also compared what they learned about climate change over
this period with what happened concurrently over the rest of the continent,
the climatic record of which stretches two additional decades back in time.
What was learned
Over the 14 years of the authors' intensive measurements, the McMurdo Dry
valleys cooled - that's right, cooled - and at the phenomenal rate of
approximately 0.7°C per decade. This dramatic cooling, in the words of the
authors, "reflects longer term continental Antarctic cooling between 1966
and 2000." In addition to sharing the same cooling trend, most of the
14-year cooling in the dry valleys occurred in the summer and autumn, just
as most of the 35-year cooling over the continent as a whole (which did not
include any data from the dry valleys) also occurred in the summer and
autumn. The authors note that this multi-faceted "compatibility with the
dry valley data increases the validity of the analysis."
Ecosystem response to the observed cooling was not good. In fact, it was -
for lack of a better word - bad. Since the thickness of ice on the
perennially ice-covered lakes in the McMurdo Dry Valleys increased by an
average of 1.5 meters over the 14-year period, underwater irradiance
declined so much that the primary productivities of the region's lakes
decreased at rates of 6-9% per year. Likewise, on the adjacent land, soil
moisture gradually dropped - from 2.2% by weight to 1.4% by weight - between
1993 and 1999, which decline is equivalent to a relative drop of 6% per
year. Hence, it was not surprising that the group of scientists determined
that the numbers of soil invertebrates (the largest animals around)
simultaneously declined by "more than 10% per year."
What it means
In the words of the authors, the continental Antarctic cooling documented in
their paper "poses challenges to models of climate and ecosystem change."
Climate models, as they note, not only predict that global warming should
have been occurring over the period of their study, but that there should
have been "amplified warming in polar regions." To instead find dramatic
cooling - which is about as different from amplified warming as one can
get - especially in one of the two places on earth where the climate models
are thought to be most correct, represents about as clear-cut a refutation
of the predictions of the climate models as one can imagine. Likewise, we
keep hearing how bad global warming will be for the biosphere, when for
Antarctica it is cooling that is decimating its meager ecosystems.
Ian St. John
"John" <x...@xx.com> wrote in message
news:91daa.417095$sV3.11...@news3.calgary.shaw.ca...
>
John. Failing to get his head out of his ass, managed to cut and paste shit
from
> From:
> http://www.co2science.org/journal/2002/v5n5c1.htm
The well known source of disinformation and distortion.
>
> Thirty-Five Years of Climate Change in Antarctica
That much, at least is true. Actually climate change in Antarctica has a
much longer history...
>
> Reference
> Doran, P.T., Priscu, J.C., Lyons, W.B., Walsh, J.E., Fountain, A.G.,
> McKnight, D.M., Moorhead, D.L., Virginia, R.A., Wall, D.H., Clow, G.D.,
> Fritsen, C.H., McKay, C.P. and Parsons, A.N. 2002. Antarctic climate
> cooling and terrestrial ecosystem response. Nature advance online
> publication, 13 January 2002 (DOI 10.1038/nature710).
>
> What was done
So far so good.
> Between 1986 and 2000, the authors measured a number of meteorological
> parameters in the McMurdo Dry Valleys of Antarctica, while they
> simultaneously measured various characteristics of the region's indigenous
> life forms. They also compared what they learned about climate change
over
> this period with what happened concurrently over the rest of the
continent,
> the climatic record of which stretches two additional decades back in
time.
Yup. This was presented many years ago when the issue first arose. It is
consistent with the erratic warming and cooliing of various areas with
changes in the polar vortex and stratosphere, probably caused by ozone
depletion and a teleconnection to global warming.
http://www.sciam.com/article.cfm?articleID=00078FDB-D9ED-1D29-97CA809EC588EE
DF
"Two atmospheric scientists have now resolved these seemingly disparate
trends. David W. J. Thompson of Colorado State University and Susan Solomon
of the National Oceanic and Atmospheric Administration Aeronomy Laboratory
in Boulder, Colo., say that summertime changes in a mass of swirling air
above Antarctica can explain 90 percent of the cooling and about half of the
warming, which has typically been blamed on the global buildup of
heat-trapping greenhouse gases. But this new explanation doesn't mean that
people are off the hook. Thompson and Solomon also found indications that
the critical atmospheric changes are driven by Antarctica's infamous ozone
hole, which grows every spring because of the presence of
chlorofluorocarbons (CFCs) and other human-made chemicals in the
stratosphere. "
>
> What was learned
> Over the 14 years of the authors' intensive measurements, the McMurdo Dry
> valleys cooled - that's right, cooled - and at the phenomenal rate of
> approximately 0.7°C per decade. This dramatic cooling, in the words of
the
> authors, "reflects longer term continental Antarctic cooling between 1966
> and 2000."
The study was of the *McMurdo Dry Valleys*. Only 4% of the continental
landmass. There was no study of the entire continent so the authors
assumption of a general cooling trend is unsupported.
> In addition to sharing the same cooling trend, most of the
> 14-year cooling in the dry valleys occurred in the summer and autumn, just
> as most of the 35-year cooling over the continent as a whole (which did
not
> include any data from the dry valleys) also occurred in the summer and
> autumn.
The authors went out of their way to try to extend a local cooling ( now
rather better understood in terms of the climate processes by the
Thompson/Solomon paper) to the continental data. The *same* data was studies
for years by many prominent climate scientists and resulted in a very slight
warming or no change. That they get a large cooling similar to their dry
valley study just shows that they were too focussed on what they were
*trying* to prove rather than looking at what *was there*. Such agendas are
somewhat career damaging and usually involve junior scientists without the
experience to know how far to 'extend' their conclusions.
> The authors note that this multi-faceted "compatibility with the
> dry valley data increases the validity of the analysis."
A fine example of gobbledegook. The analysis is either valid or not.
>
> Ecosystem response to the observed cooling was not good. In fact, it
was -
> for lack of a better word - bad. Since the thickness of ice on the
> perennially ice-covered lakes in the McMurdo Dry Valleys increased by an
> average of 1.5 meters over the 14-year period, underwater irradiance
> declined so much that the primary productivities of the region's lakes
> decreased at rates of 6-9% per year. Likewise, on the adjacent land, soil
> moisture gradually dropped - from 2.2% by weight to 1.4% by weight -
between
> 1993 and 1999, which decline is equivalent to a relative drop of 6% per
> year. Hence, it was not surprising that the group of scientists
determined
> that the numbers of soil invertebrates (the largest animals around)
> simultaneously declined by "more than 10% per year."
There is no debate about the fact that the McMurdo Dry Valleys are one of
the areas that cooled.
>
> What it means
> In the words of the authors, the continental Antarctic cooling documented
in
> their paper "poses challenges to models of climate and ecosystem change."
The challenges have been answered by both studies contradicting their
extension of the dry valley to the whole continent and by studies that are
focussing in on the changes to stratosphere mvoements that seem to be
driving the changes. You will note that Mr. Johns previous try at confusion
included a paper that demostrated
http://earthsciences.gsfc.nasa.gov/ESU/2000.03.17.ESU.html
"The satellite data, however, uniquely shows regional patterns in the trends
with a large part of the East Antarctic ice sheet having a negative trend
and the central area, including the South Pole and the Ross Ice Shelf,
having a positive trend. ".
The selection and twisting of facts to support an agenda is central to the
CO2SCIENCE scam.
> Climate models, as they note, not only predict that global warming should
> have been occurring over the period of their study, but that there should
> have been "amplified warming in polar regions."
False. The IPCC study of GCMs note that changes to the polar regions are not
robustly estimated by GCMs and generally are not mentioned in the scientific
analysys. THe IPCC did say "over land at higher latitudes" which is
demonstrated to be happening.
http://faldo.atmos.uiuc.edu/RESEARCH/temptrends.html
Also note that another paper indicated..
"It is the increased rate of meridional transport of heat that has resulted
in higher near surface air temperatures over middle and high latitudes."
This is NOT polar circulation. Nobody has ever said anything about
prediction of polar climate except the shitmongers of CO2-JUNK-SCIENCE
> To instead find dramatic
> cooling - which is about as different from amplified warming as one can
> get - especially in one of the two places on earth where the climate
models
> are thought to be most correct, represents about as clear-cut a refutation
> of the predictions of the climate models as one can imagine.
Again false. This is obviously more crap from CO2SCIENCEs illiterates. No
climate scientists would claim a regional cooling as an indication of a flaw
in global temperature trends.
> Likewise, we
> keep hearing how bad global warming will be for the biosphere, when for
> Antarctica it is cooling that is decimating its meager ecosystems.
The decimation of biology in the Dry Valleys is probably a regular thing.
The krill in the surrounding sea go through huge variations in population.
So what? That is what it is like in extreme climates
w...@bas.ac.uk
>Doran, P.T., Priscu, J.C., Lyons, W.B., Walsh, J.E., Fountain, A.G.,
>McKnight, D.M., Moorhead, D.L., Virginia, R.A., Wall, D.H., Clow, G.D.,
>Fritsen, C.H., McKay, C.P. and Parsons, A.N. 2002. Antarctic climate
>cooling and terrestrial ecosystem response. Nature advance online
>publication, 13 January 2002 (DOI 10.1038/nature710).
Response:
"Doran et al. claim that there has been a net cooling of the entire
continent between 1966 and 2000, particularly during summer and autumn.
We argue that this result has arisen because of an inappropriate
extrapolation of station data across large, data-sparse areas of
the Antarctic."
JOHN TURNER*, JOHN C. KING*, TOM A. LACHLAN-COPE* & PHIL D. JONES
http://www.nature.com/cgi-taf/DynaPage.taf?file=/nature/journal/v418/n6895/abs/418291b_fs.html
Note that it was Phil Jones's dataset that Doran et al based their claims
of Antarctic cooling on.
-W.
--
William M Connolley | w...@bas.ac.uk | http://www.nerc-bas.ac.uk/icd/wmc/
Climate Modeller, British Antarctic Survey | Disclaimer: I speak for myself
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