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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
National
Post
Professor R. Timothy Patterson
Wednesday, 20 June 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.
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.
GRAPHIC: Chart/Graph: Andrew Barr, National
Post; MOST SUNSPOTS IN 8,000 YEARS: (See hardcopy for
Chart/Graph) ; Graphic/Diagram:; Tim Patterson, Financial
Post; Layers in a 62-year-long slice of a mud-core sample
from about 4,400 years ago at Effingham Inlet,B.C. Thick
bright layers near the bottom indicate rapid diatom growth
during warm periods when the sun’s output was high. The
shift to dark sediment layers going up near the middle
of the core indicates an abrupt change to a rainy and
cool climate after a sharp decline in solar activity.
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