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My Nobel
Moment
By: John
R. Christy
I've
had a lot of fun recently with my tiny (and unofficial)
slice of the 2007 Nobel Peace Prize awarded to the
lntergovernmental Panel on Climate Change (IPCC). But,
though I as one of thousands of IPCC
participants, I don't think I will add "0.0001 Nobel
Laureate" to my resume.
The other
'half of the prize was awarded to former Vice President Al
Gore, whose carbon footprint would stomp my neighborhood
flat. But that's another story.
Both halves
of the award honor promoting the message that Earth's
temperature is rising due to human-based emissions of
greenhouse gases. The Nobel committee praises Mr. Gore and
the IPCC for
"alerting us
to a potential catastrophe and for spurring us to a
carbonless economy.
I'm sure the
majority (but not all) of my IPCC colleagues cringe when I
say this, but I see neither the developing catastrophe nor
the smoking gun proving that human activity is to blame for
most of
the warming
we see. Rather, I see a reliance on climate models (useful
but never "proof") and the coincidence that changes in
carbon dioxide and global temperatures have loose similarity
over time.
Not all of
us climate scientists are panicked about global warming.
There are
some of us who remain so humbled by the task of measuring
and understanding the extraordinarily complex climate system
that we are skeptical of our ability to know
what it is
doing and why. As we build climate data sets, from scratch
and look into the guts of the climate system, however, we
don't find the alarmist theory matching observations.
(The
National Oceanic and Atmospheric Administration satellite
data we analyze at the University of Alabama in Huntsville
does show modest warming - around 2.5 degrees
Fahrenheit
per century, if current warming trends of 0.25 degrees per
decade continue.)
It is my
turn to cringe when I hear overstated confidence from those
who describe the projected evolution of global weather
patterns over the next 100 years, especially when
I consider
how difficult it is to accurately predict that system's
behavior over the next five days.
Mother
Nature simply operates at a level of complexity that is, at
this point, beyond the mastery of mere mortals (such as
scientists) and the tools available to us. As my high school
physics
teacher admonished us in those
we-shall-conquer-the-world-with-a-slide-rule days, "Begin
all of your scientific pronouncements with 'At our present
level of ignorance,
we think we
know . . .”
I haven't
seen that type of climate humility lately. Rather
I see jump to conclusions advocates and, unfortunately, some
scientists who see in every weather anomaly the specter
of a
global-warming apocalypse. Explaining
each successive phenomenon as a result of human action gives
them comfort and an easy answer.
Others
of us scratch our heads and try to understand the real
causes behind what we see. We discount the possibility that
everything is caused by human actions, because
everything we've seen the climate do has
happened
before. Sea levels rise and fall
continually. The Arctic ice cap has shrunk before. One
millennium there are hippos swimming in the Thames, and a
geological blink later there is an ice bridge linking Asia
and
North
America.
One of the
challenges in studying global climate is keeping a global
perspective, especially when much of the research focuses on
data gathered from spots around the globe.
Often observations
from one
region get more attention than equally valid data from
another.
The recent
CNN report "Planet in Peril," for instance, spent
considerable time discussing shrinking Arc tic sea ice
cover. CNN did not note that winter sea ice around
Antarctica last month set a
record
maximum (yes, maximum) for coverage since aerial
measurements started.
Then there
is the challenge of translating global trends to local
climate. For instance, hasn't global warming led to the
five-year drought and fires in the U.S. Southwest?
Not
necessarily.
There has
been a drought, but it would be a stretch to link this
drought to carbon dioxide. If you look at the 1,000-year
climate record for the western U.S. you will see not
five-year but
50-year-Iong droughts. The 12th and 13th centuries were
particularly dry. The inconvenient truth
is that the last century has been fairly benign in the
American West. A return to the region's
long-term
"normal" climate would present huge challenges for urban
planners.
Without a
doubt, atmospheric carbon dioxide is increasing due
primarily to carbon-based energy production (with its
undisputed benefits to humanity) and many people ardently
Believe
we must "do
something" about its alleged consequence, global warming.
This might seem like a legitimate concern given the
potential disasters that are announced almost daily, so I've
looked at a
couple of ways in which humans might reduce CO2 emissions
and their impact on temperatures.
California
and some Northeastern states have decided to force their
residents to buy cars that average 43 miles-per-gallon
within the next decade. Even if you applied this law to the
entire world,
the net
effect would reduce projected warming by about 0.05 degrees
Fahrenheit by 2100, an amount so minuscule as to be
undetectable. Global temperatures vary more than that from
day to day.
Suppose you
are very serious about making a dent in carbon emissions and
could replace about 10% of the world's energy sources with
non-CO2-emitting nuclear power by 2020-roughly
equivalent
to halving U.S. emissions. Based on IPCC-like
projections, the required 1,000. new nuclear power plants
would slow the warming by about 0.2 degrees Fahrenheit per
century.
It's a
dent.
But what is
the economic and human price, and what is it worth given the
scientific uncertainty?
My
experience as a missionary teacher in Africa opened my eyes
to this simple fact: Without access to
energy, life is brutal and short. The uncertain impacts of
global warming far in the future
must be
weighed against disasters at our doorsteps today. Bjorn
Lomborg's Copenhagen-Consensus 2004, a cost-benefit analysis
of health issues by leading economists (including three
Nobelists),
calculated
that spending on health issues such as micronutrients for
children, HIV/AIDS and water purification has benefits 50 to
200 times those of attempting to marginally limit "global
warming."
Given the
scientific uncertainty and our relative impotence regarding
climate change, the moral imperative here seems clear to me.
Mr. Christy
is director of the Earth System Science Center at
the University of Alabama in Huntsville and a
participant
in the U.N.'s Intergovernmental Panel on Climate Change,
corecipient
of this
year's Nobel Peace
Prize.
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