Brian Ellis wrote:

 >
 > However, even Greenpeace postulates that the hockey stick may well be
right:
 >
 >>
According to the Cambridge International Dictionary of English the
definition of "postulate"  verb [I or T] to suggest a theory, idea, etc.
as a basic principle from which a further idea is formed or developed."

But Greenpeace postulating (or even opining) that the hockey stick is
right doesn't make it so.

It is convenient to credit "Greenpeace" with such postulations, that way
we can never get an answer to the question, "Well, is Greenpeace a
qualified statistician competent to assess the quality of the data or
the conclusions drawn from it?"  I would like the identity and the
qualifications of the person or persons at Greenpeace who postulates
that the "hockey stick" is right.

But consider the recent work done by Stephen McIntyre and Ross
McKitrick. McKitrick is with the Department of Economics, University of
Guelph, Ontario, Canada. I believe McIntyre is a successful Canadian
businessman. In a paper recently published in the British periodical
"Energy & Environment" Vol.14, No. 6, 2003 they report [from the abstract]
"The data set of proxies of past climate used in Mann, Bradley and
Hughes (1998) [the report which produced what is commonly known as the
"Hockey Stick"] ("MBH98" hereafter) for the estimation of temperatures
from 1400 to 1980 contains collation errors, unjustifiable truncation or
extrapolation of source data, obsolete data, geographical location
errors, incorrect calculations of principal components and othe quality
control defects. We detail these errors and defects. We then apply MBH98
methodology to the construction of a Northern Hemisphere average
temperature index for the 1400 - 1980 period, using corrected and
updated source data. The major finding is that the values in the early
15th centruy exceed any values in the 20th century. The particular
"hockey stick" shape derived inthe MBH98 proxy construction - a
temerature index that decreases slightly between the early 15th centruy
and early 20th century and then increases dramatically up to 1980 - is
primarily an artefact of poor data handling, obsolete data and incorrect
calculation of principal components."

The entire article can be found at
http://www.multi-science.co.uk/ee_openaccess.htm

The debate can be found at
http://www.uoguelph.ca/~rmckitri/research/trc.html


Brian also states:

  In any case, isn't this rather academic when we are faced with vast
increases of
 > atmospheric CO2 and correlated increased global average temperatures
over more
 > than a century, as shown by the business end of the hockey stick?

Correlation, even strong correlation, is evidence of nothing. There is a
strong correlation between people who had coffee with their breakfast
and fatal car accidents on the way to work.  Correlation proves nothing
other than a coincidence in time and or space, it does not prove causation.

I won't deny a correlation between higher levels of CO2 and warmer
climate, but maybe that is because warmer temperatures lead to higher
levels of CO2.

The following is an Associated Press article from a couple years ago.

(Thursday December 6, 2001) AP Article:

Study Suggests Mars Ice Caps Eroding


By PAUL RECER, AP Science Writer
WASHINGTON (AP) - Vast fields of carbon dioxide ice are eroding from the
poles of Mars, suggesting that the climate of the Red Planet is warming
and the atmosphere is becoming slightly more dense.

Experts say that over time such changes could allow water to return to
the Martian surface and turn the frigid planet into a "shirt-sleeve
environment."

Michael A. Caplinger, a scientist with Malin Space Science Systems, said
that if the rate of carbon dioxide erosion from the Mars poles continues
for thousands of years, "then it could profoundly amend the climate of
Mars."

"You would go from having to wear a spacesuit to just wearing a coat and
an oxygen atmosphere," said Caplinger.

Caplinger is co-author of a study appearing in the journal Science that
analyzes photos of Mars taken by an orbiting spacecraft. The photos were
taken in 1999 and in 2001, a period of time that represents one Martian
year. Mars is farther from the sun than the Earth and it takes the Red
Planet about 23 months to complete one year, a single solar orbit.

Observers have long known that in the Martian winter there is a snow of
carbon dioxide caused as temperatures plunge and the gas freezes out of
Mars' thin atmosphere.

But the new study suggests that a dense cap of frozen carbon dioxide
thought to be permanent at each of the Mars poles may not be all that
permanent, said Caplinger.

"It is eroding away at a rapid pace and is going to continue to do
that," said Caplinger. "This is not a seasonal change."

He said the photos suggest that the polar caps are dense slabs of frozen
carbon dioxide that may have been deposited over centuries, much like
the way seasonal snow on Earth accumulates to form a glacier.

"This stuff has been there for quite a while," he said. "It is packed
down and very smooth. We don't see evidence that it is blowing around or
drifting."

Instead, said Caplinger, the glacier-like carbon dioxide ice is eroding,
rather like the way a glacier melts on Earth.

The key clue, he said, comes from examining the light patterns on pits
at the Martian south pole. Comparing pictures taken a Martian year apart
show that the pits are getting wider and deeper as a result of the
retreat of the carbon dioxide ice, said Caplinger.

As the C02 ice erodes, it adds carbon dioxide to the Martian atmosphere,
causing the "air" to get thicker over time. This would enable the planet
to hold more of the sun's heat and, perhaps, eventually warm the whole
planet enough for water to return to the Martian surface.

Caplinger said it is not known if there is enough carbon dioxide in the
polar caps to bring about such an atmospheric change.

But his co-author, Michael C. Malin, said in a statement that if the
atmosphere of Mars becomes dense enough, it would "permit liquid water
to persist at or near the surface."

Other studies have shown that Mars was once awash with great basins of
water, but the water is thought to have disappeared or become subsurface
ice as the planet cooled and developed a thin C02 atmosphere.

Some experts suggested that any speculation about a Martian climate
change is premature.

"This is a really neat observation," said Allan H. Treiman of the Lunar
and Planetary Institute in Houston. But he said the pictures span a time
too short to make predictions about permanent changes in the Mars climate.

"We don't have enough data on Mars to draw any clear conclusions about
climate change," he said.



Chuck Dolci