The Australian Cherry - picking contrarian geologists tend to obscure
scientific truth
Geoff Seidner
13 Alston Grove
East St Kilda 3183
03 9525 9299
Cherry-picking contrarian geologists tend to obscure scientific truth
- The Australian
- December 31, 2011
To
listen to prominent "contrarian" geologists such as Ian Plimer, you might
imagine she never could.
But,
despite the bluster, our contrarian geologists are out of kilter with their own
community and seem deeply confused about the way the greenhouse effect - by
adding more CO2 to the atmosphere, for example - has shaped both the past and
the present.
All
geology students learn of the importance of the greenhouse effect. It's simply
impossible to understand the geological record without it.
In
his 2001 award-winning book A Short History of Planet Earth, Plimer has numerous
references to the greenhouse effect.
He
explains what all young geologists learn as the faint young sun paradox:
"The
early sun had a luminosity of some 30 per cent less than now and, over time,
luminosity has increased in a steady state.
"The
low luminosity of the early sun was such that the Earth's average surface
temperature would have been below 0C from 4500 to 2000 million years ago. But
there is evidence of running water and oceans as far back as 3800 million years
ago." The question is, what kept the early Earth from freezing over?"
Plimer
goes on to explain: "This paradox is solved if the Earth had an enhanced
greenhouse with an atmosphere of a lot of carbon dioxide and methane."
Here's
another quote from Plimer, referring to a time 100 million years ago when the
dinosaurs roamed the planet: "The peak of 6 per cent carbon dioxide was at the
time of a protracted greenhouse and maximum sea level. At this time, mean annual
surface temperatures were 10C to 15C warmer than now."
The
problem is, although his temperature estimate is about right, his CO2 estimate
is about 50 times too high. CO2 levels were more like 0.12 per cent. At just
three times present levels, this is a target we are on track to reach early next
century.
Jump
forward to 2009 and in his book Heaven and Earth Plimer seems to have quietly
forgotten those geological lessons in stating: "Over geological time there is no
observed relationship between global climate and atmospheric CO2."
Exactly
which Plimer are we
to
believe?
Scientists
are notoriously sceptical of the data collected by others. But ignoring a
respected source is reprehensible. Cherry-picking only the data that fits is
borderline. Deliberately misrepresenting data or making it up is just not
on.
Here's
an example. In a section from his new book, How To Get Expelled from School, as
reprinted in The Weekend Australian recently, Plimer claims: "Antarctic ice core
(Siple) shows that there were 330 parts per million of carbon dioxide in the air
in 1900; Mauna Loa Hawaiian measurements in 1960 show that the air then had
260ppm carbon dioxide."
Plimer
goes on to say: "Either the ice core data is wrong, the Hawaiian carbon dioxide
measurements are wrong, or the atmospheric carbon dioxide content was decreasing
during a period of industrialisation."
The
implication is there must be something terribly wrong with the orthodox climate
science and we are all being taken for a ride.
The
problem is that the primary data sources explicitly state the Hawaiian Mauna Loa
CO2 measurements for 1960 were in the range 313-320ppm, and that Siple air of
age about 1900 has a CO2 content of 295ppm, with the 330ppm concentrations
having an estimated air age of 1962-83, entirely in keeping with Mauna Loa.
Who
has been taken for a ride?
Sadly,
this is not an isolated case. Plimer has persistently claimed that volcanoes
contribute much more CO2 to the Earth's atmosphere than do our own activities,
blithely ignoring US Geological Survey reference data showing just the opposite
- volcanoes emit CO2 at about 1 per cent of the rate of anthropogenic
emissions.
Another
common meme promoted by our contrarian geologists is that it is now a fact that
the climate is cooling.
But
may we ask by whose data is this a fact?
Certainly
not NASA's, which showed last year was the hottest on record, followed by 2005,
2007, 2009 and 1998. In fact, NASA ranks nine of the hottest 10 years ever
recorded between 2001 and last year. You'd reckon NASA had learned a few lessons
about being careful with data.
Variations
on decadal timescales are more relevant to climate trends than annual
variations. NASA shows the average temperature over the decade 2000-09 was a
full 0.2C higher than in the 1990s - the biggest decadal rise in temperature
ever recorded.
With
an increase of more than 0.5C over the past 40 years, the decadal trend is now
warming faster than ever. It beggars belief that any serious scientist could
assert the climate is cooling.
Our
contrarian geologists also avoid the devil in the detail. NASA's data shows that
winters are warming faster than the summers and the Arctic faster than the
tropics. While the lower atmosphere is warming, the upper atmosphere is
cooling.
These
characteristics provide diagnostic fingerprints of the heat trapping expected
for a greenhouse effect. They provide the smoking gun that points to rising
greenhouse gas levels as
the
cause, and rule out warming because of additional heat input from the sun.
Could
that be why you won't hear our contrarian geologists refer to such data? Could
their real agenda be in manufacturing doubt rather than the search for
scientific truth?
If
so, it wouldn't be a first, as Naomi Oreskes points out in her recent book
Merchants of Doubt: How a Handful of Scientists Obscured the Truth on Issues
from Tobacco Smoke to Global Warming.
Now
here's a point for those who, like Rinehart, think all geologists toe Plimer's
contrarian line.
Oreskes
is a noted geologist. Having published groundbreaking research on the origin of
the giant South Australian Olympic Dam deposit, she has arguably contributed
more to the understanding of Australian mineral wealth than has Plimer.
Now
just imagine a meeting between Rinehart and Oreskes - that would be
interesting!
Mike
Sandiford is professor of geology at the University of
Melbourne
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