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<text id=89TT0039>
<title>
Jan. 02, 1989: Global Warming:Feeling The Heat
</title>
<history>
TIME--The Weekly Newsmagazine--1989
Jan. 02, 1989 Planet Of The Year:Endangered Earth
</history>
<article>
<source>Time Magazine</source>
<hdr>
PLANET OF THE YEAR, Page 36
GLOBAL WARMING - Feeling the Heat
</hdr><body>
<p>THE PROBLEM: Greenhouse gases could create a climatic calamity
</p>
<p>By Michael D. Lemonick
</p>
<p> For more than a decade, many scientists have warned that
cars and factories are spewing enough gases into the atmosphere
to heat up the earth in a greenhouse effect that could
eventually produce disastrous climate changes. But until
recently, the prophets of global warming garnered about as much
attention as the religious zealots who insist that Armageddon is
near. When Colorado Senator Timothy Wirth held congressional
hearings on the greenhouse effect in the fall of 1987, the
topic generated no heat at all. "We had a very, very
distinguished panel," Wirth recalled at the TIME Environment
Conference, "and who was in the cavernous hearing room? Six or
seven people, and two or three of them were lost tourists."
</p>
<p> So Wirth decided to schedule another hearing in the summer,
hoping hot weather would make people pay attention to the
greenhouse issue. Sure enough, when the hearing convened last
June 23, the thermometer read 99 degrees F, a Washington record
for that day. The room was packed when James Hansen, head of
NASA's Goddard Institute for Space Studies, turned global
warming into front-page news at last. "It is time to stop
waffling so much," he declared. "The evidence is pretty strong
that the greenhouse effect is here."
</p>
<p> Hansen thus became perhaps the most prominent scientist
willing to say straight out that the earth-warming effect of
excess carbon dioxide (CO2) and other gases generated by
industry and agriculture had crossed the line from theory into
fact. By itself, Hansen's bold assertion was dramatic enough.
But the unusual string of weather-related disasters that struck
the world last summer could not have been better timed to drive
his point home. The heat waves, droughts, floods and hurricanes
may be previews of what could happen with ever increasing
frequency if the atmosphere warms 3 degrees F to 8 degrees F by
the middle of the next century, as some scientists predict.
</p>
<p> On the other hand, the summer's disasters may have had
nothing to do with the greenhouse effect. They could have been
random events -- all part of the natural year-to-year
variations in weather. Many climatologists called Hansen's
remarks premature and feared that if this summer happens to be
cool, public worries about the greenhouse effect will quickly
fade.
</p>
<p> Unfortunately, scientists cannot agree on how much global
warming has occurred, how much more is on the way and what the
climatic consequences will be, giving policymakers an excuse for
delay. But no one disputes the fact that the amount of CO2 in
the atmosphere has risen and continues to increase rapidly and
that the human race is thus conducting a dangerous experiment
on an unprecedented scale. The possible consequences are so
scary that it is only prudent for governments to slow the
buildup of CO2 through preventive measures, from encouraging
energy conservation to developing alternatives to fossil fuels.
</p>
<p> Some forecasters have suggested that the impact of global
warming will not be uniformly bad around the world. After all,
Canada would not complain if the productive corn-growing lands
of the U.S. Midwest shifted north across the border, and the
Soviet Union might welcome a warmer, more hospitable Siberia.
But while the broad outlines of a hotter world are easy to
draw, more specific projections are riddled with uncertainty,
since the regional weather patterns that would prevail are
largely unpredictable. If Canada becomes much dryer than it is
now, for example, higher temperatures will not help much.
</p>
<p> Moreover, while some nations will probably end up with a
more benign climate than they now have, the pace of change
could be so jarring that the benefits would be lost. "We're
talking about rates of climate change perhaps 100 times faster
than at any time in human history," said Stephen Schneider of
the National Center for Atmospheric Research. Ecosystems will
not be able to adjust so quickly, he said, "and the faster
things change, the more likely it is that the impact will be
negative." Warned Thomas Lovejoy of the Smithsonian Institution:
"There will be no winners in this game of ecological chairs, for
it will be fundamentally disruptive and destabilizing, and we
can anticipate hordes of environmental refugees dwarfing the
numbers of the Dust Bowl era or the boat people."
</p>
<p> Ironically, the same greenhouse effect that may be so
dislocating made earth hospitable to life in the first place.
Without a heat-trapping blanket of naturally occurring CO2, the
planet would have an average surface temperature of only 0
degrees F instead of 59 degrees F. Reason: like the glass panes
of a greenhouse, CO2 molecules are transparent to visible light,
allowing the sun's rays to warm the earth's surface. But when
the surface gives off its excess heat, it does so not with
visible light but with infrared radiation. And since CO2
absorbs infrared rays, some of the excess heat stays in the
atmosphere rather than escaping into space. How much heat is
retained depends on how much CO2 is in the air.
</p>
<p> Recent research has confirmed that this is more than just
theory. By drilling deep into Antarctic and Arctic ice,
scientists have been able to measure the amount of CO2 in air
bubbles trapped in ancient layers of snow. They have also
looked at fossilized plant tissues for clues as to how warm the
air was during the same period. The conclusion: CO2 levels and
global temperatures have risen and fallen together, over tens
of thousands of years. And there is evidence from space: Mars,
which has little CO2 in its atmosphere, has a surface
temperature that reaches -24 degrees F at best, while Venus,
with lots of CO2, is a hellish 850 degrees F.
</p>
<p> The ebb and flow of CO2 on earth was caused by only natural
processes until less than 200 years ago. With the arrival of the
Industrial Revolution in the early 1800s, man suddenly threw a
new factor into the climatic equation. Carbon dioxide is
released in large quantities when wood and such fossil fuels as
coal, oil and natural gas are burned. As society
industrialized, coal-burning factories began releasing CO2
faster than plants and oceans, which absorb the gas, could
handle it. In the early 1900s, people began burning oil and gas
at prodigious rates. And increasing population led to the
widespread cutting of trees in less developed countries. These
trees are no longer available to soak up excess CO2, and whether
they are burned or left to rot, they instead release the gas.
By the late 1800s atmospheric CO2 had risen to between 280 and
290 parts per million. Today it stands at 350 p.p.m., and by
2050 it could reach 500 to 700 p.p.m., higher than it has been
in millions of years.
</p>
<p> But carbon dioxide, once thought to be exclusively
responsible for the greenhouse effect, is now known to cause
only half the problem. The rest comes from other gases.
Chlorofluorocarbons, or CFCs, are not only destroyers of the
stratosphere's ozone layer but powerful greenhouse gases as
well. So are nitrogen oxides, which are pollutants spewed out
of automobile exhausts and power-plant smokestacks. Another
greenhouse gas is methane, the primary component of natural
gas. Methane is also generated by bacteria living in the guts
of cattle and termites, the muck of rice paddies and the
rotting garbage in landfills. Each of these sources is fostered
by human activity -- even the termites, which thrive in the
clearings left after tropical rain forests are cut down.
Humanity's contribution to the greenhouse effect comes from so
many basic activities that man cannot realistically expect to
stop the process, only slow it down.
</p>
<p> A first step toward doing that is to ban the production of
CFCs, which are used to make plastic foam and as coolants in
refrigerators and air conditioners. These gases account for an
estimated 15% of the greenhouse effect. Another strategy is to
burn as much methane as possible. That adds CO2 to the air, but
getting rid of the methane is well worth it. Both gases trap
heat, but as a greenhouse gas, methane traps 20 times as much
heat as carbon dioxide, molecule for molecule.
</p>
<p> Methane from cattle feedlots will be very difficult to
collect, but the gas in garbage landfills is already being
tapped and burned at many sites around the U.S. At the Fresh
Kills landfill on New York City's Staten Island, for example,
methane that would otherwise have escaped into the air is being
collected by a gas company and used to heat thousands of homes.
The technique essentially involves driving a pipe into the
depths of the garbage, then trapping the gas that rushes out.
This should be done at all landfills.
</p>
<p> Another step that could be taken to counteract global
warming is to slow -- and ideally stop -- deforestation. But
that is an enormously complex task, and so a simple companion
strategy should be adopted at the same time: the planting of
trees, and plenty of them, to absorb CO2 from the air. "It
surely has to be one of the most benign things we can do," said
Gus Speth of the World Resources Institute. Tree planting can be
encouraged at all levels of society, from individuals putting an
extra tree or two in their backyards to local communities and
private organizations planting an acre at a time to provincial
and national governments reforesting on a more widespread basis.
</p>
<p> Admittedly, trees are just a stopgap. Unless a tree is used
for lumber, it eventually dies and rots or is burned, releasing
whatever CO2 it has absorbed. But since the rapid pace of change
may be the greatest danger posed by global warming, stopgaps
could be important. If nothing else, reforestation will buy time
to put other preventive measures into place.
</p>
<p> Tree planting will have negligible impact, however, if
people continue to pump CO2 into the atmosphere at current
rates. While wood and fossil-fuel burning will never be
eliminated, they can be cut down significantly. An immediate
way to do so is through conservation. When oil prices soared in
the 1970s, industries responded by becoming much more energy
efficient. But the plunge in the price of oil from $36 per bbl.
in 1982 to less than $12 per bbl. this fall has cooled the
enthusiasm for conservation. Governments must rekindle that
interest and boost energy saving by setting or raising minimum
efficiency standards for automobiles, appliances and other
machinery.
</p>
<p> Although developed countries waste the most energy, there
are plenty of opportunities for conservation in the developing
world, where energy-using equipment tends to be older and more
inefficient. Third World conservation would not only help slow
greenhouse warming but also let countries save money by reducing
dependence on energy imports. If the industrialized countries
expect cooperation, though, they should make available at
minimal cost the most advanced energy-saving technology,
especially for power plants, and help finance the purchase.
</p>
<p> By far the most efficient and effective way to spur
conservation is to raise the cost of fossil fuels. Current
prices fail to reflect the very real environmental costs of
pumping carbon dioxide into the air. The answer is a tax on CO2
emissions -- or a CO2 user fee, if that is a more palatable
term. The fee need not raise a country's overall tax burden; it
could be offset by reductions in income taxes or other levies.
</p>
<p> Imposing a CO2 fee would not be as difficult as it sounds.
It is easy to quantify how much CO2 comes from burning a gallon
of gasoline, a ton of coal or a cubic yard of natural gas. Most
countries already have gasoline taxes; similar fees, set
according to the amount of CO2 produced, could be put on all
fossil-fuel sources. At the same time, companies could be given
credits against their CO2 taxes if they planted trees to take
some of the CO2 out of the air.
</p>
<p> A user fee would have benefits beyond forcing a cutback in
CO2 emissions. The fuels that generate carbon dioxide also
generate other pollutants, like soot, along with nitrogen
oxides and sulfur dioxide, the primary causes of acid rain. The
CO2 tax would be a powerful incentive for consumers to switch
from high-CO2 fuels, such as coal and oil, to power sources
that produce less CO2, notably natural gas. When burned,
methane generates only half as much CO2 as coal, for example,
in producing the same amount of energy.
</p>
<p> Ultimately, though, the world must move away from fossil
fuels for most of its energy needs. Said Berrien Moore,
director of the Institute for the Study of the Earth, Oceans and
Space at the University of New Hampshire: "Even if you cut
emissions of CO2 in half, the atmospheric concentration will
keep going up. You're still adding CO2 faster than you're
withdrawing it, so the balance keeps rising."
</p>
<p> Of all the known nonfossil energy sources, only two are far
enough along in their development to be counted on: solar and
nuclear, neither of which generates any greenhouse gases at all.
Solar power is especially attractive. It produces no waste, and
it is inexhaustible. Not all solar power comes directly from the
sun: both wind and hydroelectric power are solar, since wind is
created by the sun's uneven warming of the atmosphere and since
the water that collects behind dams was originally rain, which
in turn was water vapor evaporated by solar heating.
</p>
<p> But wind and hydroelectric power can be generated at only a
relatively few sites, and so governments should redouble
financing for research to develop efficient, low-cost
photovoltaic power. Photovoltaic cells, which produce electric
current when bathed in sunlight, were briefly in vogue during
the energy crises of the 1970s, and while public attention and
Government funding have waned, research into the technology has
continued. "The capital costs have come down from about $50 a
peak watt to $5," said Speth. If they drop to $1, solar power
will become competitive. That could happen without significant
Government research support -- but it will happen sooner with
it.
</p>
<p> Sometime early in the next century, solar enthusiasts hope
to see vast tracts of photovoltaic collectors providing cheap
electricity that can be transmitted over long distances.
Alternatively, the electricity could be used to produce hydrogen
from water. That could open up all sorts of possibilities. Cars,
for example, could be redesigned to run on hydrogen, and that
would produce a dramatic reduction in CO2 emissions.
</p>
<p> Nuclear power is more controversial; until recently the mere
mention of it made environmentalists blanch. They had good
reason, considering the accidents at Three Mile Island and
Chernobyl, the problem of radioactive waste and the horror
stories about U.S. weapons plants. But the greenhouse effect is
forcing some antinuclear activists to rethink their position. "I
was a strong opponent of the nuclear program in France," said
Brice Lalonde, France's Environment Under Secretary and a
former presidential candidate on the Ecologist Party ticket.
"Now I am reassessing the whole thing." France gets more than
70% of its electricity from nuclear plants and has an impressive
safety record.
</p>
<p> Reactors in France, like all conventional reactors, depend
for their safety in part on the skill and alertness of their
operators. To minimize the risk of human error, engineers have
developed designs for much safer types of nuclear reactors. But
while these reactors, like experimental solar cells, show great
promise, they are not yet economical enough to go on-line in
significant numbers. It should therefore be a priority of
governments to spend more money on research aimed at lowering
the cost of safe nuclear and solar power and making them
primary energy sources. Otherwise the global warming that
results from overreliance on fossil fuels could produce an
increasingly uncertain and potentially bleak future.
</p>
</body></article>
</text>