Text 29153, 235 rader
Skriven 2007-06-21 19:06:00 av Jeff Binkley (1:226/600)
Ärende: Global Warming
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http://www.canada.com/nationalpost/financialpost/comment/story.html?id=5
97d0677-2a05-47b4-b34f-b84068db11f4&p=4
Read the sunspots
The mud at the bottom of B.C. fjords reveals that solar output drives
climate change - and that we should prepare now for dangerous global
cooling
R. TIMOTHY PATTERSON, Financial Post
Published: Wednesday, June 20, 2007
Politicians and environmentalists these days convey the impression that
climate-change research is an exceptionally dull field with little left
to discover. We are assured by everyone from David Suzuki to Al Gore to
Prime Minister Stephen Harper that "the science is settled." At the
recent G8 summit, German Chancellor Angela Merkel even attempted to
convince world leaders to play God by restricting carbon-dioxide
emissions to a level that would magically limit the rise in world
temperatures to 2C.
The fact that science is many years away from properly understanding
global climate doesn't seem to bother our leaders at all. Inviting
testimony only from those who don't question political orthodoxy on the
issue, parliamentarians are charging ahead with the impossible and
expensive goal of "stopping global climate change." Liberal MP Ralph
Goodale's June 11 House of Commons assertion that Parliament should have
"a real good discussion about the potential for carbon capture and
sequestration in dealing with carbon dioxide, which has tremendous
potential for improving the climate, not only here in Canada but around
the world," would be humorous were he, and even the current government,
not deadly serious about devoting vast resources to this hopeless
crusade.
Climate stability has never been a feature of planet Earth. The only
constant about climate is change; it changes continually and, at times,
quite rapidly. Many times in the past, temperatures were far higher than
today, and occasionally, temperatures were colder. As recently as 6,000
years ago, it was about 3C warmer than now. Ten thousand years ago,
while the world was coming out of the thou-sand-year-long "Younger
Dryas" cold episode, temperatures rose as much as 6C in a decade -- 100
times faster than the past century's 0.6C warming that has so upset
environmentalists.
The Deniers: The National Post's series on scientists who buck the
conventional wisdom on climate science.
The National Post is a Canadian national newspaper. Here is the series
so far:
Statistics needed -- The Deniers Part I
Warming is real -- and has benefits -- The Deniers Part II
The hurricane expert who stood up to UN junk science -- The Deniers Part
III
Polar scientists on thin ice -- The Deniers Part IV
The original denier: into the cold -- The Deniers Part V
The sun moves climate change -- The Deniers Part VI
Will the sun cool us? -- The Deniers Part VII
The limits of predictability -- The Deniers Part VIII
Look to Mars for the truth on global warming -- The Deniers Part IX
Limited role for C02 -- the Deniers Part X
End the chill -- The Deniers Part XI
Clouded research -- The Deniers Part XII
Allegre's second thoughts -- The Deniers XIII
The heat's in the sun -- The Deniers XIV
Unsettled Science -- The Deniers XV
Bitten by the IPCC -- The Deniers XVI
Little ice age is still within us -- The Deniers XVII
Fighting climate 'fluff' -- The Deniers XVIII
Science, not politics -- The Deniers XIX
Gore's guru disagreed -- The Deniers XX
The ice-core man -- The Deniers XXI
Some restraint in Rome -- The Deniers XXII
Discounting logic -- The Deniers XXIII
Dire forecasts aren't new -- The Deniers XXIV
They call this a consensus? - Part XXV
NASA chief Michael Griffin silenced - Part XXVI
Forget warming - beware the new ice age - Part XXVII
Climate-change research is now literally exploding with new findings.
Since the 1997 Kyoto Protocol, the field has had more research than in
all previous years combined and the discoveries are completely
shattering the myths. For example, I and the first-class scientists I
work with are consistently finding excellent correlations between the
regular fluctuations in the brightness of the sun and earthly climate.
This is not surprising. The sun and the stars are the ultimate source of
all energy on the planet.
My interest in the current climate-change debate was triggered in 1998,
when I was funded by a Natural Sciences and Engineering Research Council
strategic project grant to determine if there were regular cycles in
West Coast fish productivity. As a result of wide swings in the
populations of anchovies, herring and other commercially important West
Coast fish stock, fisheries managers were having a very difficult time
establishing appropriate fishing quotas. One season there would be
abundant stock and broad harvesting would be acceptable; the very next
year the fisheries would collapse. No one really knew why or how to
predict the future health of this crucially important resource.
Although climate was suspected to play a significant role in marine
productivity, only since the beginning of the 20th century have accurate
fishing and temperature records been kept in this region of the
northeast Pacific. We needed indicators of fish productivity over
thousands of years to see whether there were recurring cycles in
populations and what phenomena may be driving the changes.
My research team began to collect and analyze core samples from the
bottom of deep Western Canadian fjords. The regions in which we chose to
conduct our research, Effingham Inlet on the West Coast of Vancouver
Island, and in 2001, sounds in the Belize-Seymour Inlet complex on the
mainland coast of British Columbia, were perfect for this sort of work.
The topography of these fjords is such that they contain deep basins
that are subject to little water transfer from the open ocean and so
water near the bottom is relatively stagnant and very low in oxygen
content. As a consequence, the floors of these basins are mostly
lifeless and sediment layers build up year after year, undisturbed over
millennia.
Using various coring technologies, we have been able to collect more
than 5,000 years' worth of mud in these basins, with the oldest layers
coming from a depth of about 11 metres below the fjord floor. Clearly
visible in our mud cores are annual changes that record the different
seasons: corresponding to the cool, rainy winter seasons, we see dark
layers composed mostly of dirt washed into the fjord from the land; in
the warm summer months we see abundant fossilized fish scales and
diatoms (the most common form of phytoplankton, or single-celled ocean
plants) that have fallen to the fjord floor from nutrient-rich surface
waters. In years when warm summers dominated climate in the region, we
clearly see far thicker layers of diatoms and fish scales than we do in
cooler years. Ours is one of the highest-quality climate records
available anywhere today and in it we see obvious confirmation that
natural climate change can be dramatic. For example, in the middle of a
62-year slice of the record at about 4,400 years ago, there was a shift
in climate in only a couple of seasons from warm, dry and sunny
conditions to one that was mostly cold and rainy for several decades.
Using computers to conduct what is referred to as a "time series
analysis" on the colouration and thickness of the annual layers, we have
discovered repeated cycles in marine productivity in this, a region
larger than Europe. Specifically, we find a very strong and consistent
11-year cycle throughout the whole record in the sediments and diatom
remains. This correlates closely to the well-known 11-year "Schwabe"
sunspot cycle, during which the output of the sun varies by about 0.1%.
Sunspots, violent storms on the surface of the sun, have the effect of
increasing solar output, so, by counting the spots visible on the
surface of our star, we have an indirect measure of its varying
brightness. Such records have been kept for many centuries and match
very well with the changes in marine productivity we are observing.
In the sediment, diatom and fish-scale records, we also see longer
period cycles, all correlating closely with other well-known regular
solar variations. In particular, we see marine productivity cycles that
match well with the sun's 75-90-year "Gleissberg Cycle," the 200-500-
year "Suess Cycle" and the 1,100-1,500-year "Bond Cycle." The strength
of these cycles is seen to vary over time, fading in and out over the
millennia. The variation in the sun's brightness over these longer
cycles may be many times greater in magnitude than that measured over
the short Schwabe cycle and so are seen to impact marine productivity
even more significantly.
Our finding of a direct correlation between variations in the brightness
of the sun and earthly climate indicators (called "proxies") is not
unique. Hundreds of other studies, using proxies from tree rings in
Russia's Kola Peninsula to water levels of the Nile, show exactly the
same thing: The sun appears to drive climate change.
However, there was a problem. Despite this clear and repeated
correlation, the measured variations in incoming solar energy were, on
their own, not sufficient to cause the climate changes we have observed
in our proxies. In addition, even though the sun is brighter now than at
any time in the past 8,000 years, the increase in direct solar input is
not calculated to be sufficient to cause the past century's modest
warming on its own. There had to be an amplifier of some sort for the
sun to be a primary driver of climate change.
Indeed, that is precisely what has been discovered. In a series of
groundbreaking scientific papers starting in 2002, Veizer, Shaviv,
Carslaw, and most recently Svensmark et al., have collectively
demonstrated that as the output of the sun varies, and with it, our
star's protective solar wind, varying amounts of galactic cosmic rays
from deep space are able to enter our solar system and penetrate the
Earth's atmosphere. These cosmic rays enhance cloud formation which,
overall, has a cooling effect on the planet. When the sun's energy
output is greater, not only does the Earth warm slightly due to direct
solar heating, but the stronger solar wind generated during these "high
sun" periods blocks many of the cosmic rays from entering our
atmosphere. Cloud cover decreases and the Earth warms still more.
The opposite occurs when the sun is less bright. More cosmic rays are
able to get through to Earth's atmosphere, more clouds form, and the
planet cools more than would otherwise be the case due to direct solar
effects alone. This is precisely what happened from the middle of the
17th century into the early 18th century, when the solar energy input to
our atmosphere, as indicated by the number of sunspots, was at a minimum
and the planet was stuck in the Little Ice Age. These new findings
suggest that changes in the output of the sun caused the most recent
climate change. By comparison, CO2 variations show little correlation
with our planet's climate on long, medium and even short time scales.
In some fields the science is indeed "settled." For example, plate
tectonics, once highly controversial, is now so well-established that we
rarely see papers on the subject at all. But the science of global
climate change is still in its infancy, with many thousands of papers
published every year. In a 2003 poll conducted by German environmental
researchers Dennis Bray and Hans von Storch, two-thirds of more than 530
climate scientists from 27 countries surveyed did not believe that "the
current state of scientific knowledge is developed well enough to allow
for a reasonable assessment of the effects of greenhouse gases." About
half of those polled stated that the science of climate change was not
sufficiently settled to pass the issue over to policymakers at all.
Solar scientists predict that, by 2020, the sun will be starting into
its weakest Schwabe solar cycle of the past two centuries, likely
leading to unusually cool conditions on Earth. Beginning to plan for
adaptation to such a cool period, one which may continue well beyond one
11-year cycle, as did the Little Ice Age, should be a priority for
governments. It is global cooling, not warming, that is the major
climate threat to the world, especially Canada. As a country at the
northern limit to agriculture in the world, it would take very little
cooling to destroy much of our food crops, while a warming would only
require that we adopt farming techniques practiced to the south of us.
Meantime, we need to continue research into this, the most complex field
of science ever tackled, and immediately halt wasted expenditures on the
King Canute-like task of "stopping climate change."
R. Timothy Patterson is professor and director of the Ottawa-Carleton
Geoscience Centre, Department of Earth Sciences, Carleton University.
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