Evidence has mounted that global warming began in the last century
and that humans are, at least in part, responsible. The concern is that
the warming of our climate will greatly affect its habitability for
many species, including humans. Both the Intergovernmental Panel on
Climate Change (IPCC) and the U.S. National Academy of Sciences concur
that this is the case. But some argue that this thinking is too
limited. They say that too many scientists are either ignoring, or
don't understand, the well-established fact that Earth's climate has
changed rapidly in the past and could change rapidly in the future—in
either direction.
Evidence for abrupt climate change is readily found in ice cores taken
from Greenland and Antarctica. One of the best known examples of such
an event is the Younger Dryas cooling of about 12,000 years ago, named
after the arctic wildflower found in northern European sediments. This
event began and ended rather abruptly, and for its entire 1000 year
duration the North Atlantic region was about 5°C colder. Could
something like this happen again? It could, and because the
changes can happen all within one decade—we might not even see it
coming.
The Younger Dryas occurred at a time when orbital forcing should have
continued to drive climate to the present warm state. The unexplained
phenomenon has been the topic of much intense scientific debate, as
well as other millennial scale events.
An 11-year low in Sunspot activity has raised fears among a small
number of scientists that rather than getting warmer, the Earth could
possibly be about to return to another cooling period. The idea is
especially intriguing considering that most of the world is in
preparation for global warming. Could we be preparing for the wrong
scenario?
A sunspot is a region on the Sun that is cooler than the rest and
therefore appears darker. One theory is that a strong solar magnetic
field, which causes plenty of sunspot activity, protects the earth from
cosmic rays, but that when the field is weak - during low sunspot
activity - the rays can penetrate into the lower atmosphere and cloud
cover increases, which in turn leads to a cooler surface.
Geophysicist Phil Chapman, the first Australian to become an astronaut
with NASA, notes that pictures from the US Solar and Heliospheric
Observatory show that there are currently no spots on the sun. He
believes this is the reason why the world cooled rapidly between
January last year and January this year, by about 0.7C.
“This is the fastest temperature change in the instrumental record, and
it puts us back to where we were in 1930,” Dr Chapman wrote in The
Australian. “If the temperature does not soon recover, we will
have to conclude that global warming is over.”
However, scientists from the US National Center for Atmospheric
Research published a report in 2006 that claims the Sun likely has a
negligible effect on climate change. Another study, recently published
study in the Institute of Physics’ Environmental Research Letters, by
researchers from Lancaster and Durham Universities found that there was
no strong correlation between cosmic rays and the production of low
cloud cover. If that is correct, it would mean the lack of sunspots is
not necessarily an indicator of higher cloud cover and subsequent
future cooling.
While it's true that some world regions have experienced record colds
recently, other areas do seem to be warming up. In Australia, The
Bureau of Meteorology says that temperatures there have been warmer
than the 1960-90 average since the late 1970s. Even though there have
been some cooler years mixed in, overall they are now 0.3C higher than
the long-term average. Other countries are experiencing similar upward
trends. On the other hand, since widespread temperature records have
only been kept for a relatively short period of the Earth's history,
it's hard to know exactly what these increases mean from a long-term
perspective.
Cooling, or "Little Ice Age" proponents like Chapman, say that it could
still swing either way. He proposes preventive measures to slow any
potential cooling, such as bulldozing Siberian and Canadian snow to
make it dirty and less reflective. “My guess is that the odds are now
at least 50:50 that we will see significant cooling rather than warming
in coming decades.”
Canadian scientist Kenneth Tapping of the National Research Council has
noted that solar activity has entered into an unusually inactive
phase, but what that means—if anything—is still anyone's guess. Another
scientist, Oleg Sorokhtin, a fellow of the Russian Academy of Natural
Sciences agrees with Chapman. Sorokhtin believes that, in spite of the
results of certain recent studies, lack of sunspots does indicate a
coming cooling period. In fact, he calls manmade climate change “a drop
in the bucket” compared to the cold brought on by inactive solar phases.
But while Sorokhtin is advising people to “stock up on fur coats”, the
vast majority of prominent scientists believe the bulk of evidence
points towards an overall warming trend, and that anomalies and
exceptions to the rule do not make a significant dent in this consensus.
The Daily Galaxy asked climate expert Thomas Reichler, what he has to
say about it. According to him, anyone claiming that the Earth isn't
getting warmer, or that it's perhaps even getting colder, simply isn't
looking at the actual data.
"There is absolutely no doubt that the world is in a warming phase,"
Reichler told the Daily Galaxy, "and that conclusion is supported by
99% of all serious scientists, so I'm certainly not alone in that
certainty."
Reichler is probably right, but it wouldn't be the first time if the
fringe opinion turned out to be onto something. But from a broader
perspective, does it really matter who's "right" as far as preparations
go? Whether the climate gets cooler or warmer, or does nothing at all,
people will still need massive amounts of energy. Even if we were to
take the reverse approach and intentionally increase greenhouse gases
in the atmosphere in order to stave off cooling, it would likely have
little effect other than to further pollute the environment with
standard energy consumption's many toxic byproducts
Solar Cycle 24 began in early 2008 , but has shown minimal
activity through early 2009. The small changes in solar
irradiance that occur during the solar cycle exert a small influence on
Earth's climate, with periods of intense magnetic activity producing
slightly higher temperatures, and solar minimum periods such as that
seen in 2008 and early 2009 likely to have the opposite effect.
Skeptics have been saying that global temperature rises might be due
to changes in the sun, pretty much the ultimate “it wasn’t us, a big
boy did it,” with a giant fusion reactor as the elusive culprit.
Researchers have shown that this isn’t the case and unlike the original
claim, their work involves advanced computer models, a distinct lack of
the word “might”, and has been published in Science.
Carnegie
Mellon University’s Peter Adams along with Jeff Pierce from Dalhousie
University in Halifax, Canada, have developed a model to test the
controversial hypothesis that says changes solar activity are causing
global warming.
The hypothesis they tested was that increased
solar activity reduces cloudiness by variations in cosmic rays. So,
when clouds decrease, more sunlight is let in, causing the earth to
warm. Some climate change skeptics have tried to use this hypothesis to
suggest that greenhouse gases may not be the global warming culprits
that most scientists agree they are. They found that changes in the
concentration of particles that affect clouds are 100 times too small
to affect the climate.
Professors Peter Adams and Jeff Pierce did a bunch of things that those throwing around the solar excuse didn’t:
a) They did detailed work analyzing the actual effects of such activity
b) They actually understood what such effects would really even be
c)
They rigorously applied scientific procedures to this research,
constructed computer models, and would have reported the results either
away
d) They spent many, many years earning PhDs in scientific research and the title of “Professor.”
We have to say, d) is our favorite.
The
simulations show that the effects of cosmic rays from the sun are
barely 1% of what they’d have to be to explain what we’ve seen. The
scientists are even one step ahead of the “maybe-sorta” game, admitting
their simulations can’t account for everything that exists, because
nothing could ever do that (including their opponents’ arguments), but
pointing out that nothing omitted or missed could skew the results
enough to appreciably alter the results.
Posted by Luke McKinney with Rebecca Sato and Casey Kazan.
Changes in the Sun are not causing Global Warming, Study Says
Related Galaxy posts:
Abrupt Climate Change: Inevitable Surprises
Cosmic Rays -The Cause of Global Warming?
The Milky Way Enigma -How Galactic Forces May Control Life on Earth
Are Global Warming Models Accurately Predicting Our Future? New Study Reveals the Answer—A Galaxy Interview
As Temperatures Hit Record Lows, Global Warming Takes a Punch to the Gut
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