[ RadSafe ] ...- CO2 consequences
Jaro
jaro-10kbq at sympatico.ca
Mon Sep 18 17:57:25 CDT 2006
This article in Commentary magazine (which also mentions nuclear, BTW), will
likely prompt a good deal of responses....
Jaro
^^^^^^^^^^^^^^^^^^^^^
http://www.commentarymagazine.com/article.asp?aid=12202044_1
Global Warming: Apocalypse Now?
Kevin Shapiro
In 1906 the Swedish chemist Svante Arrhenius published a popular book
speculating on the origins of the earth and of life upon it. (An English
translation, Worlds in the Making, appeared in 1908.) In a nutshell,
Arrhenius proposed that the solar system was born of a collision between
cool stars, with the sun and the planets forming from the resulting nebular
debris. The planets, he thought, were then seeded by living spores that had
been propelled through the cosmos by electromagnetic radiation.
Unfortunately for Arrhenius, few of these ideas ever achieved wide currency,
and most of them were considered far-fetched even at the turn of the last
century. One, however, has lately experienced something of a revival: the
notion that the earths climate is maintained within bounds that are
favorable to life by the concentration of carbon dioxide (CO2) in the
atmosphere. As early as 1896, Arrhenius had proposed that surface
temperatures rise in proportion to atmospheric CO2, which absorbs radiated
heat that would otherwise escape into space. Noting that CO2 can be
generated by the burning of coal, Arrhenius predicted that the growth of
industry might eventually result in a warmer planet (in modern terms, this
would be called anthropogenic forcing)-a salutary outcome from a
Scandinavian point of view, since a more temperate climate would likely be a
boon to agriculture in the North.
This greenhouse effect is the cornerstone of the contemporary notion of
global warming.1 A hundred years after Arrhenius wrote, the concentration of
CO2 in the atmosphere has already nearly doubled, and the earths surface is
on average about 0.6°C warmer-enough to convince many scientists and
laypeople that Arrhenius was right at least about this. In 2001, the
official estimate of the Intergovernmental Panel on Climate Change was that
we should expect a warming of about 3°C, give or take a few degrees, in the
decades ahead.
But todays prophets of climate change are not quite so sanguine as
Arrhenius about the prospect of anthropogenic forcing. This is because,
according to some models, even a relatively small rise in global mean
temperature would result in dramatic changes in local climate patterns.
While climate modelers generally agree that farmers in subarctic latitudes
will benefit from warmer summers and milder winters, their forecast for the
rest of the planet approximates the apocalypse: famine, drought, hurricanes,
floods, mass extinctions-the list goes on. Most of these calamities, said to
be of such a scale that they could threaten the viability of human
civilization, are predicted to result from changes in weather patterns that
would follow from rising temperatures in the oceans and the lower
atmosphere.
_____________________
The earths climate is an extraordinarily complex system, and most
climatologists would probably concur that local perturbations cannot be
foretold with precision. But given the magnitude of the prospective problem,
many pundits and policymakers-with the backing of the scientific
establishment-have become less interested in improving our understanding of
climate change than in pressing for an immediate solution. By this they mean
somehow reducing (or at least stabilizing) the concentration of CO2 in the
atmosphere.
This is a difficult proposition, to say the least. About 70 percent of
electricity in the United States is generated by the combustion of fossil
fuels, mostly coal; our transportation network, which accounts for about a
quarter of our greenhouse-gas emissions, is almost entirely dependent on
petroleum. The picture in the rest of the world is not much better, as
economic pressures dictate the construction of new coal-fired power plants
not only in China and India but also in Germany and Eastern Europe. Despite
all the fanfare surrounding Russias ratification of the Kyoto Protocol in
November 2004, bringing the treaty into force, most experts agree that,
because of relatively modest emissions targets, allowances for international
trading of carbon credits, and the exemption of major polluters like China,
it will have no discernible impact on global CO2 emissions.
Nevertheless, as the intellectual class has increasingly become convinced of
the reality of man-made climate change-recent converts range ideologically
from Gregg Easterbrook of the liberal New Republic to Ron Bailey of the
libertarian Reason-environmentalists have correspondingly stepped up their
efforts to build public support for some sort of action. The media now
regularly proclaim the impending reality of climate change and encourage
alarm. ABC News, offering not so much as a bow toward a scientific approach,
recently asked viewers to submit stories about global warming in their own
communities. Even the July 2006 issue of Condé Nast Traveler, not generally
known for coverage of science and technology issues, includes tips for
travelers who feel guilty about the damaging emissions generated by their
airplane flights.
Among the more serious efforts to sway the debate are two new books, Tim
Flannerys The Weather Makers: How Man Is Changing the Climate and What It
Means for Life on Earth2 and Elizabeth Kolberts Field Notes from a
Catastrophe,3 along with Al Gores much ballyhooed film, An Inconvenient
Truth. Each of these presents a more or less comprehensive view of the
scientific case for global warming, and describes in vivid detail some of
the changes already attributed to rising temperatures: melting permafrost in
Alaska, the crack-up of the Larsen B ice shelf in Antarctica, thinning sea
ice in the Arctic, fiercer and more numerous hurricanes in the Atlantic. And
each suggests that the threat of global warming is supported by an
overwhelming scientific consensus that, in their view, leaves absolutely no
room for dissent.
_____________________
The basic elements of the consensus are relatively easy to comprehend.
Indeed, the three most important have already been mentioned. One is that
surface thermometers have registered a global mean increase in temperature
of about 0.6°C over the last century, give or take 0.15°C. This means that
global temperatures are now higher than they have been in at least a
thousand years, and perhaps since before the last major ice age. Likewise,
atmospheric CO2 has increased from preindustrial levels of around 250 parts
per million by volume (ppmv) to around 378 ppmv, a level probably not seen
since the Pliocene era, around 3.5 million years ago, when atmospheric CO2
was higher for reasons that are basically unknown. There is little doubt,
however, that at least some of the current increase is attributable to human
activity.
So much for the data. The rest of what we know about global warming comes
from intricate computer simulations, called general circulation models (or
GCMs), which make use of these data and innumerable other observations
about the earths atmosphere in order to predict the effects of continuing
increases in CO2. Almost all the models forecast more warming, with the
amount depending on various assumptions built into them. Although it is not
clear from these results exactly why we should be alarmed-more on this
later-Kolbert, Flannery, and Gore do their best to make sure that we are
alarmed, enough to be willing to take drastic action. Each of them takes a
slightly different rhetorical tack, but the ultimate message is always the
same: we are on the verge of a catastrophe.
Kolberts book, which grew out of a series of articles written for the New
Yorker in 2005, adopts a journalistic style; she reports from the front
lines, as it were, embedding her essential points in well-crafted vignettes
and conversations with scientists. She treks to Alaska, where an expert in
permafrost tells her that temperatures have already become dangerously high.
In Greenland, she observes cracks and crevasses in the ice sheet, which seem
to suggest that the islands glaciers are melting. Experts on mosquitos,
frogs, and butterflies attest to ecological changes that similarly portend a
warming earth. Some people, it seems, have already bitten the bullet:
Kolbert describes how the Dutch are abandoning their 500-year-old battle
against the seas, dismantling their dikes and designing floating houses.
Despite its grim tidings, Field Notes is almost a pleasure to read, thanks
to Kolberts casually elegant prose and attention to detail. Indeed, the
anecdotal approach makes for a story both more interesting and less
convincing than Kolbert might have hoped. By allowing scientists to present
the case for global warming in their own words, Kolbert perhaps
inadvertently gives the reader a glimpse into the doubts that still exist
even among the most ardent believers in the problem-and into those believers
very human biases.
As compared with Field Notes, Tim Flannerys The Weather Makers is more
flamboyant, more decisive, and far more belligerent. Flannery, an Australian
zoologist and something of a scientific celebrity, does little to hide his
contempt for those who fail to take the problem of climate change as
seriously as he does.
The Weather Makers starts off on an encouraging note, with an acknowledgment
that climate change is difficult to evaluate impartially because the
scientific issues are bound up in competing political and economic
interests. Unfortunately, this pretense of evenhandedness collapses by the
first chapter, which introduces the Gaia hypothesis-roughly, the idea that
the earths oceans, soil, atmosphere, and living creatures function together
as a kind of superorganism, resisting changes that would alter the global
climate. It is our failure to adopt a Gaian view, Flannery suggests, that
has led us into the current global-warming predicament. (James Lovelock, the
British scientist who proposed the Gaia hypothesis in the late 1960s, has
predicted that global warming will lead to a mass extinction of the human
population-a sort of Gaian final solution to the problem of anthropogenic
pollution.)
In Flannerys view, the consensus based on climate change models is too
conservative. He thinks that climate change has already taken off in full
force, and the outlook for the future is dire indeed. Where Kolbert is
circumspect about warming trends at the poles, Flannery suggests that the
entire polar ecosystem is on the brink of collapse, and that coral reefs
bleached by overheated oceans may never recover. Droughts in the American
West, Australia, and Africa are all attributed to global warming, as are
Europes recent heat waves and floods. And this is just the beginning:
Flannery predicts a rapid rise in global temperatures that will wipe out
innumerable animal and plant species, not to mention agriculture in much of
the world.
Is there anything we can do to mitigate the coming disaster? The Weather
Makers devotes considerable attention to exploring possible solutions. These
include geosequestration (pumping CO2 back into the earths crust) and
alternative energy sources like hydrogen, nuclear, wind, and solar power.
Not surprisingly, Flannery comes down on the side of wind and solar power,
suggesting that these would be the most economical and democratic choices.
Why democratic? Because, he imagines, each community and household can
control its own electricity generation with wind farms and solar panels,
while alternatives like nuclear power will merely perpetuate corporate
control of the power grid.
Flannery reserves his greatest ire for big business, and for the
conservative politicians he sees as subservient to it. In the end, he seems
to think that if we fail to break free of our captivity to big oil and
big coal, the imperative to regulate the climate will leave us with no
choice but to submit to some sort of world government.
____________________
Somewhere in-between Kolberts measured warning and Flannerys hysterical
fearmongering lies An Inconvenient Truth. Narrated in its entirety by Al
Gore, the film is part documentary, part hagiography: ominous warnings about
the threat of climate change are interleaved with flashbacks to Gores
childhood and other formative moments in the former Vice Presidents career.
The movie covers much of the same ground as Field Notes and The Weather
Makers, but with less concern for factual accuracy. Gore all but explicitly
blames global warming for the disastrous effects of Hurricane Katrina; even
Flannery only goes so far as to offer Katrina as an example of the kind of
disaster that might become more prevalent in a warming world, and
climatologists themselves are divided over whether global warming implies an
increase in tropical-storm activity. In another segment, an animated polar
bear is shown swimming for his life in an ice-free Arctic sea. Presumably
the filmmakers resorted to animation because, in fact, most polar-bear
populations are not under such imminent threat.
Gores overall strategy is to present the worst of worst-case scenarios as
if they were inevitable, barring a miraculous reduction in atmospheric CO2.
He suggests, for example, that Greenlands ice cap is in danger of melting,
which in turn would cause the jet stream to shut down-a bit like the
scenario dramatized in the 2004 disaster film The Day After Tomorrow.
Needless to say, most earth and atmospheric scientists consider the
likelihood of such an event to be vanishingly low. Animated maps show sea
levels rising to inundate Miami, New York, and Shanghai, which is more than
even the most extreme predictions would seem to allow.
One might note that An Inconvenient Truth contains more than its share of
ironies and curious lacunae. Gore suggests that viewers can help cut back on
their own carbon emissions by taking mass transit. And yet, during much of
the movie, Gore is shown either riding in a car or traveling on a plane-by
himself. He berates Americans for our reliance on fossil fuels, but,
chatting amiably with Chinese engineers, seems peculiarly unconcerned by
Chinese plans to build hundreds of new coal-fired power plants. Indeed, he
compares vehicle-emission standards in the United States unfavorably with
Chinas. Touting renewable fuels like those derived from biomass (which at
present offer no carbon savings compared with traditional fuels), he does
not mention nuclear power or other practical carbon-reducing alternatives to
coal, oil, and gas.
In the end, An Inconvenient Truth brings nothing new to the global-warming
debate, except perhaps its insistence that the debate is over. Its
effectiveness as a film-the New York Times has called it surprisingly
engaging-hinges, one suspects, on the degree to which the viewer is likely
a priori to have a favorable view of Al Gore. Those who basically like him,
or hope to see him run again for the presidency, have described his
performance as earnest and energetic, and have found his appeal persuasive;
Franklin Foer, the editor of the New Republic, was so impressed that he
pronounced the film likely to become a seminal political document. To
others, he comes across as a self-absorbed, condescending know-it-all.
Politics aside, however, does Gore have a point? Is it really true that the
threat of climate change impels us to take action?
_____________________
The data themselves-that is to say, actual observations of the earths
climate-are hardly grounds for much excitement. For example, the fact that
global temperatures and CO2 levels are correlated in the climatological
record is not in itself cause for panic. Consider the smoking gun for many
global-warming alarmists-the Vostok ice core, an 11,775-foot-long sliver of
Antarctic ice that has allowed scientists to extrapolate atmospheric CO2 and
temperature anomalies over roughly the past 420,000 years, showing that
temperature and CO2 have risen and fallen roughly in tandem over this time
frame.
But the key word here is roughly. The Vostok data make it clear that at
the onset of the last glaciation, temperatures began to decline thousands of
years before a corresponding decline in atmospheric CO2. This observation
cannot be replicated by current climate models, which require a previous
fall in CO2 for glaciation to occur. Moreover, an analysis published in
Science in 2003 suggests that the end of one glacial period, called
Termination III, preceded a rise in CO2 by 600 to 1,000 years. One
explanation for this apparent paradox might be that global warming, whatever
its initial trigger, liberates CO2 from oceans and permafrost; this
additional CO2 might then contribute in turn to the natural greenhouse
effect.
Should we worry that adding even more CO2 to the atmosphere by burning
fossil fuels could contribute to a runaway warming effect? Probably not. In
simple physical terms, each extra unit of CO2 added to the atmosphere
contributes less to the greenhouse effect than the previous unit, just as
extra layers of paint applied to a pane of glass contribute less and less to
its opacity. For this reason, we have already experienced 75 percent of the
warming that should be attributable to a simple doubling of atmospheric CO2
since the late 19th century, a benchmark we have not yet reached but one
that is frequently cited as dangerous by those who fear global warming.
Moreover, it seems unlikely that we can do very much about it.
Most models, of course, predict much more warming to come. This has to do
with the way they account for the effects of clouds and water vapor, which
are assumed to amplify greatly the response to man-made greenhouse gases.
The problem with this assumption is that it is probably wrong.
Many scientists who study clouds-including MITs Richard Lindzen, a
prominent skeptic of climate-change alarmism-argue that the data show the
opposite to be true: namely, that clouds act to limit, rather than
aggravate, warming trends. In any case, the GCMs have failed miserably to
simulate observed changes in cloud cover. Flannery, to his credit, is
cognizant of this criticism, and acknowledges that the role of clouds is
poorly understood. By way of a response, he draws attention to a computer
simulation showing a high degree of correspondence between observed and
predicted cloud cover for one model on a single day-July 1, 1998. Overall,
however, GCM simulations of clouds are a source of significant error.
Indeed, the models are subject to so much uncertainty that it is hard to
understand why anyone would bother to get worked up about them. Generally
speaking, the GCMs simulate two kinds of effects on climate: natural
forcing, which includes the impact of volcanic eruptions and solar
radiation, and anthropogenic forcing, which includes greenhouse gases and
so-called aerosols, or particulate pollution. But the behavior of most of
these factors is unknown.
The major models assume, for example, that aerosols act to cancel warming;
this effect is said to explain the apparent decline in global temperatures
from the 1940s to the 1970s, when the popular imagination was briefly
obsessed with the possibility of global cooling. Some scientists, however,
are now claiming that the opposite is true, and that aerosols actually
exacerbate warming.
Whatever the case, the impact of aerosols is so poorly understood that the
term essentially refers to a parameter that can be adjusted to make the
models predictions correspond to actual observations. Making inferences
from the models about the true state of the earths climate is therefore
an exercise in circular reasoning. To be sure, the business of fine-tuning
GCMs provides a livelihood for many climatologists, and may one day yield
valuable insights into the workings of the earths climate. But the output
of these models is hardly a harbinger of the end of civilization.
_____________________
If the empirical basis for alarmism about global warming is so flimsy, it is
reasonable to ask what can account for the disproportionately pessimistic
response of many segments of society.
Part of the problem is that global warming has ceased to be a scientific
question-by which I do not mean that the interesting scientific issues have
actually been settled, but that many of those concerned about global warming
are no longer really interested in the science. As Richard Lindzen has
reminded us, the Kyoto Protocol provides an excellent illustration. Although
there is widespread scientific agreement that the protocol will do next to
nothing to affect climate change, politicians worldwide continue to insist
that it is vital to our efforts to combat the problem of global warming, and
scientists largely refrain from contradicting them.
Some have suggested that the underlying reason for this is economic. After
all, public alarm is a powerful generator of science funding, a fact that is
not lost on theorists and practitioners. In 2003, the National Research
Council, the public-policy arm of the National Academy of Sciences,
criticized a draft of the U.S. National Climate Change Plan for placing too
much emphasis on improving our knowledge about the climate and too little on
studying the likely impacts of global warming-the latter topic being sure to
produce apprehension, and hence grants for more research. By the same token,
the Kyoto process seems to lumber on in part because of the very large
number of diplomats and bureaucrats whose prestige and livelihoods depend on
maintaining the perception that their jobs are indispensable.
Money aside, it may be that many scientists have a knack for
overinterpreting the importance of their own work. It is of course exciting
to think that ones research concerns an unprecedented phenomenon with
far-reaching political implications. But not only can this lead to public
misperception, it can encourage a politicization of the scientific
literature itself. Scientists skeptical of the importance of anthropogenic
warming have testified that it is difficult to publish their work in
prestigious journals; when they do publish, their articles are almost always
accompanied by rebuttals.
In fact, the scientific consensus on climate change-at least, as it is
summarized by Gore, Flannery, and the like-includes a very large number of
disparate observations, only a small number of which are pertinent to
understanding the actual determinants of contemporary climate change. The
fact, for example, that certain species have become scarce or extinct is
frequently presented as a cause for alarm about the climate. But such
ecological shifts are often the result of idiosyncratic local conditions,
and in any case are largely irrelevant to the broader issue of global
warming.
____________________
In recent years the issue of climate change has also been used as a tool to
embarrass the political Right, and especially the Bush administration-which,
after Bill Clinton declined to submit the Kyoto Protocol to the Senate for
ratification, withdrew the U.S. signature from the pact. Although efforts to
portray conservatives as insensitive to environmental issues are not new,
what is new is the scope of the alleged problem, which requires not merely a
targeted solution (like the phasing-out of chlorofluorocarbons in response
to ozone depletion) but a radical change in our mode of energy generation
and specifically a wholesale shift away from fossil fuels.
The really curious element here is that many of those who seem to have
become convinced of the reality of climate change appear rather unwilling to
take meaningful steps toward cleaner sources of energy. Like Flannery, they
simply assert that a carbon-free economy will somehow be much more efficient
and productive than one powered by fossil fuels-because, of course, we will
be rid of evil and greedy energy companies, which many alarmists suspect are
at the root of the problem.
Practically speaking, however, they have little to offer. Very few
Democratic politicians have advocated the construction of new nuclear-power
plants, a key element of the Bush administrations energy plan and probably
our best bet to avoid an increased reliance on coal. Although Senator Edward
M. Kennedy (among other Democrats) signed a bill that would require the U.S.
to derive 20 percent of its energy from renewable sources by 2020, he has
strenuously opposed a wind farm planned off the coast of Cape Cod, visible
from his Hyannisport family estate.
The overall effect of these inconsistent policy goals-limiting fossil-fuel
consumption without activating any viable substitutes-will be to drive up
the price of energy, a move that will probably not much affect the affluent
but will be quite problematic for the rest of us. Al Gore will be able to
continue to crisscross the country by jet, while feeling virtuous about
having encouraged the shift worker to reduce his energy consumption by using
public transportation. And if the problem of global warming does not
eventuate, so much the better. Alarmists will be able to reassure themselves
that they have forestalled a catastrophe, even if this comes at considerable
expense to the economy as a whole.
There are many good reasons to wean ourselves from a dependence on fossil
fuels, not least to cease enriching unsavory regimes in places like Saudi
Arabia, Iran, and Venezuela. But in combating climate change, we should not
ignore the damage done by the proponents of global-warning themselves in
diverting money and energy away from more obvious and well-substantiated
problems. Unfortunately, many people seem to be more concerned with the
supposed menace of global warming, about which we can realistically do very
little, than with problems like infectious disease, about which we can do
quite a bit. Speaking of inconvenient truths, this is a real one.
Kevin Shapiro is a research fellow in neuroscience and a student at Harvard
Medical School. He contributed Lessons of the Cloning Scandal to the April
Commentary.
1 Technically speaking, the greenhouse effect refers to the warming
attributable to all greenhouse gases, including not only CO2 but also water
vapor, methane, and others. The contribution to the greenhouse effect of CO2
produced by combustion is properly called the Callendar effect, after the
British scientist, Guy Stewart Callendar, who proposed it in 1938.
2 Atlantic Monthly Press, 384 pp., $24.00.
3 Bloomsbury USA, 192 pp., $22.95.
==========================
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