[comp.society] Global Warming and Computer Models

haramoto@zodiac.rutgers.edu (01/05/90)

[reposted from "sci.environment"]

  On Nov. 7 the U.S. and Japan shocked environmentalists around the world by
refusing to sign a draft resolution at a Netherlands international conference
on global climate change calling for the "stabilization" of emissions of
carbon dioxide (CO2) and other "greenhouse gases" by the yaer 2000. Instead,
they made the conference drop all reference to a specific year, and to a
specific CO2 reduction target. The Bush Administration view was set forth
by D. Allan Bromley, the presidential science adviser, in testimony to
Senator Gore's subcommittee on Science, Technology & Space: "My belief is
that we should not move forward on major programs until we have a reasonable
understanding of the scientific and economic consequences of those programs."

  President Bush was immediately savaged by environmentalists, and by
politicians like Senator Gore (D-Tenn.). The Bush viewpoint does not sit too
well with most of the media, either. Last January Time published a cover story
on environmental catastrophes, declaring that greenhouse gases could create
a climatic calamity. The New York Times weighed in a month ago with a story
about how melting polar ice would flood the nations that can least afford
to defend themselves, Third World countries like Bangladesh and India. Or
perhaps you have seen the ads for Stephen Schneider's Global Warming,
accompanied by a blurb from Senator Tim Wirth (D-Colo.). In his book this
well-known climatologist paints a future of seas surging across the land,
famine on an epidemic scale and eco-system collapse.

  Is the earth really on the verge of environmental collapse? Should
wrenching changes be made in the world's industry to contain CO2 buildup?
Or could we be witnessing the 1990s version of earlier scares: nuclear
winter, cancer-causing cranberries and $100 oil? The calamitarians always
have something to worry about. Consider this: In his 1976 book, The Genesis
Strategy, Schneider lent support to the then popular view that we could
be in for another ice age, "perhaps one akin to the Little Ice Age of
1500-1850. Climate variability, which is the bane of reliable food production,
can be expected to increase along with the cooling."

  At the very moment Bromley was testifying to Gore's subcommittee, MIT's
prestigious Technology Review was reporting on the publication of an
exhaustive new study of worldwide ocean temperatures since 1850 by MIT
climatologists Reginald Newell, Jane Hsiung and Wu Zhongxiang. Its most
striking conclusion: "There appears to have been little or no global
warming over the past century." In fact, the average ocean temperature
in the torrid 1980s was only an eighth of a centigrade degree (a quarter
of a Fahrenheit degree) higher than the average of the 1860s. Ocean
temperature is now virtually the same as it was in the 1940s. Since two-
thirds of the buildup of CO2 has taken place since 1940, the MIT data
blow all of the global warming forecasts into a cocked hat. President
Bush wisely told reporters: "You can't take a policy and drive it to the
extreme and say to every country in the world, 'You aren't going to
grow at all.'"

  That is the central issue of the global warming debate, and it explains
why the U.S. and Japanese position was supported by some 30 other developing
nations which see that just as Marxism is giving way to markets, the political
"greens" seem determined to put the world economy back into the red, using
the greenhouse effect to stop unfettered market-based economic expansion.

  In simplest terms, the earth's atmosphere does operate as a greenhouse. In
addition to oxygen, nitrogen and water vapor, the atmosphere contains several
gases that trap radiated heat, including methane and CO2. Carbon dioxide
is essential not only to warmth but to vegetation. It is also essential
to life in another way: Without its heat-containing effect the planet would
freeze, like the atmospherically naked moon.

  Throughout most of human history that atmospheric blanket has held global
temperatures at an average of about 60 degrees F., plus or minus 5 degrees F.
During most of human history, the CO2 concentration in that blanket has,
until this century, hovered around 270 parts per million, although in
earlier geologic epochs it reached as high as 20,000.

  Over the last 100 years the CO2 concentration has risen from 270 to today's
level of 350. The culprit: man. Most of the greenhouse gas increase is the
result of fossil fuel consumption. Add to that the rise in other man-generated
trace gases - methane, nitrogen oxides and chlorofluorocarbons - and total
greenhouse gases are now at 410 ppm. In other words, because of the combined
effect of these gases, we have already gone over halfway to a doubling of
CO2. Even so, there has been less than a half a degree of warming in the
last 100 years.

  What do the environmental pessimists make of all this? The earliest versions
of their computer "general circulation models" predicted that the earth would
warm up by anywhere from 3 to 5 degrees centrigrade, or 5 to 9 degrees
Fahrenheit, by the year 2050. The most extreme scenarios warn of coastal
flooding (from melting ice caps) and rising inland droughts. However, as the
level of sophistication of the models has risen, these forecast effects have
been steadily reduced to a new range of 1.5 to 2.5 degrees centigrade.

  One major exception to this declining rate of doom is the model run by
James Hansen of the National Aeronautics & Space Administration, who shocked
a congressional hearing in June 1988 during the middle of a scorching near-
nationwide drought, by saying he was "99% confident" the greenhouse effect is
now here.

  Even though the vast majority of the climatological community was outraged
by Hansen's unproven assertions, environmental advocate Stephen Schneider
notes in Global Warming, "Journalists loved it. Environmentalist were
estatic. Jim appeared on a dozen or more national television news programs..."

  By the end of 1988, with Hansen and Schneider's enthusiastic support, global
warming was deeply embedded in the public consciousness. Now over 60% of the
public is convinced it will worsen, even as the evidence of that alleged
trend is under increasingly sharp and solid scientific attack.

  On the contrary, that attack has been used as a premise for even more
immediate action. As one TV anchorman argued, "Even if we aren't sure it's
true, shouldn't we take precautions and act now as if it were?"

  Unfortunately, "taking such precautions" could well spell the end of the
American dream for us and the world. Once CO2 is in the atmosphere, we can't
easily remove it. Since most of the forecast rise in the gas is a function
of simple economic and population growth in the Third World, there is no
realistic economic way to prevent a CO2 doubling without slashing growth
and risking a revolt of the have-not nations against the haves. The
Washington, D.C.-based Center for Strategic & International Studies points
out that, even though the U.S. is now the largest carbon fuel user, it's
the developing countries that will quadruple their energy consumption by
2025. "By the middle of the next century, they will account for the bulk
of the greenhouse gases emitted into the atmosphere, even if they succeed
in doubling energy efficiency."

  The Environmental Protection Agency finds that just to stabilize U.S.
CO2 emissions at present levels would force 30% taxes on oil and coal,
while to meet environmentalists' demands for a 20% reduction in U.S. CO2
emmissions would require a tax of $25 per barrel on oil, and $200 a ton
on coal, effectively doubling U.S. energy costs.

  Unfortunately, the popular media don't seem to care. In May the national
press erupted in a two-day firestorm when Hansen told Senator Gore's sub-
committee that the Office of Management & Budget had censored his florid
global warming testimony by adding the modest caveat, "These changes should
be viewed as estimates from evolving computer models and not as reliable
predictions."

  Yet, at the moment of that testimony, 61 of the world's top climatologists,
gathered for a five-day workshop in Amherst, Mass., were largely agreeing
with OMB. Science magazine reported that most of the attendees were
pleasantly surprised by OMB's efforts to control Hansen: "I can't say I
agree with censorship, but it seems OMB has better people than I thought.
I'd have to agree with their angle," said Rick Katz of the National Center
for Atmospheric Research, on eof the leading modelers.

  Conference leader Michael Schlesinger, another top modeler (University of
Illinois), agreed: "[Hansen's] statements have given people the feeling the
greenhouse effect has been detected with certitude. Our current understanding
does not support that. Confidence in its detection is now down near zero."

  That conclusion was buttressed by one of the deans of U.S. climatology,
Reid Bryson, a founder of the Institute for Environmental Studies at the
University of Wisconsin, who said in July: "The very clear statements that
have been made [by Hansen] that the greenhouse warming is here already
and that the globe will be 4 degrees [centigrade] warmer in 50 years cannot
be accepted."

  On Dec. 24, 1988, Hansen received an unwelcome Christmas present in the
form of a new research paper by one of the world's most universally respected
climatologists, Thomas Karl, and two of his colleagues at the National
Oceanographic & Atmospheric Administration, Kirby Hanson and George Maul.
Their review of the best climate record in the world - that of the 48
contiguous United States - concluded: "There is no statistically significant
evidence of an overall increase in annual temperature or change in annual
precipitation for the contiguous U.S. 1895-1987." Look at the chart on
pages 96-97. As Karl says in an interview, "If there is a greenhouse warming
effect, you can't find it in the U.S. records."

  That news alone should have cooled off the global warming movement. But the
environmentalists accepted Hansen's dismissal of the paper as "not signifi-
cant" because the data covered only 1.5% of the earth's surface, not nearly
enough to identify major trends.

  But MIT meteorologist Richard Lindzen says that Hansen's rebuttal is out
of line. He points out that because of the law of large numbers - the fact
that a large enough sample is likely to give an accurate picture of a larger
population - "the absence of any trend in the record of the contiguous U.S.
leads to the suspicion that all the trends in the global record may be
spurious."

  The major reason for this is that when you fully subject global temperature
records (as Karl did the U.S. records) to adjustments for the effects of
unbanization (cities are heat islands that artificially inflate temperature
records), the global warming trend since 1880 has been only a third of a
degree centigrade, and over the Northern Hemisphere land masses, no trend
at all.

  Here's another fact, noted by Hugh Ellsaesser of Lawrence Livermore
Laboratories, that should trouble the calamity theorists: Most of the past
century's warming trend took place by 1938, well before the rise in CO2
concentration. From 1938 to 1970 temperatures plunged so sharply a new ice
age was widely forecast. Furthermore, the warming trend since 1976 has been
just the opposite of that forecast by the greenhouse model, with cooling
in both the northern Pacific and North Atlantic.

  In fact, the Northern Hemisphere shows no net change over the last 55 years,
during which CO2 concentration rose from approximately 300 to 350 ppm and
other thermally active trace gases were in their steepest growth phases.

  In spite of this clear lack of correlated warming evidence, one of the
leading climate models now predicts that a 1% annual rise in CO2 should,
over 30 years, produce a 0.7-degree centigrade warming. But when Patrick
Michaels of the University of Virginia applied that formula to the period
from 1950 to 1988, when greenhouse gases rose 1.2% per year, he found a
tiny 0.2-degree warming in land temperatures, where the model would have
predicted 1.3 degrees. When a model cannot come within 500% of explaining
the past, it is useless as a predictor of anything.

  As Reid Bryson concludes in a 1988 paper, "A statement of what the climate
is going to be in the year A.D. 2050 is a 63-year forecast. Do the models
have a demonstrated capability of making a 63-year forecast? No. A 6.3-year
forecast? No. Have they successfully simulated the climate variation of the
past century and a half? No. They are marvels of mathematics and computer
science, but rather crude imitators of reality."

  The major weakness of the models is their assumption that the CO2 buildup
is the significant climate variable, and should ceteris paribus (all other
things being equal) generate warming. But, as it turns out, the ceteris
are decidely not paribus.

  One of those variables is cloud cover, which is at least 100 times more
powerful in affecting temperatures than greenhouse gases and is infinitely
variable. Yet, because cloud cover has been documented only for a decade
or so (by weather satellites), the models have have little to go on. Until
recently, the modelers assumed that warmth gave rise to the kind of clouds
that trap heat, contributing still further to warming, in a vicious cycle.
But in June 1988, V. Ramanathan of the University of Chicago and a team
of scientists at NASA concluded from preliminary satellite data that "clouds
appear to cool earth's climate," possibly offseting the atmospheric green-
house effect.

  The supreme irony is that this "cooling effect," most pronounced in the
Northern Hemisphere, coincides with the paths of coal-burning emission plumes
with their high concentration of sulfur-dioxide. That confirms a long-held
thesis that sulfur dioxide creates "cool clouds." Of course, it is very
upsetting to an environmentalist to discover that a pollutant has a beneficial
side effect.

  Sulfur dioxide emissions not only acidify rain, they combine with water
vapor to form what are known as "aerosols," which have the effect of
brightening clouds and making them reflect more heat away from the earth.
Wisconsin's Reid Bryson described this effect as early as 20 years ago.
Bryson's thesis was scorned at the time. But last June, Thomas Wigley, one
of England's top climatologists and global warming enthusiast, conceded in
a paper in Nature magazine that sulfur dioxide cooling "is sufficiently large
that the effects may have significantly offset the temperature changes that
resulted from the greenhouse effect."

  Michaels says this could also explain in part why U.S. daytime highs (when
brighter clouds have the most cooling effect) have actually declined
substantially in the last 50 years, even as the nighttime lows have risen.
"This should make you wonder," says Michaels, "why Hansen [and others] have
only perturbed their models with CO2 and not with SO2 as well. If you only
perturb the model with CO2, it will predict the greenhouse warming effect.
If you only perturb it with SO2, you get an ice age."

  Hugh Ellsaesser says the main reason the models have been so completely
wrong in "predicting" the past is that they completely ignore the counter-
vailing, thermostatic effects of the hydrological cycle of evaporation and
condensation. Two-thirds of the predicted global warming is due not directly
to CO2's radiative power but to an indirect effect: Carbon dioxide warming
supposedly causes a threefold amplification of water vapor surface
evaporation into the atmospheric blanket.

  But Ellsaesser says in the warmer, tropical latitudes, where the temperature
change from sea-level upward is most rapid, evaporation has the opposite
effect. There, water vapor rises by deep convection in fast-rising towers.
This in turn leads to more rapid condensation and precipitation, which then
causes a drying and thinning of the upper atmosphere in a process called
subsidence. "In the lower latitudes, a rise in CO2 emissions will produce
a 3-to-1 rise in greenhouse blanket *thinning* due to condensation. That's
exactly opposite to what the models predict," he says.

  As eminent British scientist, Sir James Lovelock, says this hydrological
process "is comparable in magnitude with that of the carbon dioxide green-
house, but in opposition to it." National Oceanographic scientist Thomas
Karl agrees: "We will eventually discover how naive we have been in not
considering CO2's effects on cloud cover and convection. As CO2 speeds up
the hydrological cycle, more convection creates more clouds and more cooling.
So, the greenhouse effect could turn out to be minimal, or even benign."

  MIT's Richard Lindzen thinks that correcting for deep convection alone
could lower the global warming estimates by a factor of six. As a result,
he says, "It is very unlikely that we will see more than a few tenths of
a degree centigrade from this cause [CO2] over the next century."

  In the face of such mounting evidence, U.S. businesses may stop worrying
about devastating legislative enactments. That could be a mistake. As Nobel
economist James Buchanan argues, what drives Washington policymaking is not
economic or scientific realities, but "public choice," the pursuit of power
and funding.

  The public choice potential of global warming is immense. Under a global
warming scenario, the EPA would become the most powerful government agency
on earth, involved in massive levels of economic, social, scientific and
political spending and interference, on a par with the old Energy Department.
Don't forget the energy crisis: During the 1970s, a great many less-than-
honest scientists confidently predicted the world was about to run out of
fossil fuels, and that by 1985, we'd be paying $100 a barrel for oil, or
more. We wasted billions on energy subsidies.

  Senator Albert Gore is evidence of this public choice phenomenon. He seems
determined to run his next presidential campaign at least in part on climate
change, saving Mother Earth. Every year, at least one-sixth of the U.S. is
classified by the government's Palmer Index as being in drought. Even though
that index overstates the case, Gore could be looking at some very big
political states - maybe California or Texas or Iowa - where his message
will resonate with farmers and business. All he has to do is wait for a
warm spell, and capitalize on what mathematicians call noise in the
statistics.

  Patrick Michaels explains: "We know that the Pacific Ocean current known
as El Nino tends to warm and cool in two-year cycles. Just as its warming
cycle produced 1987-88 droughts, in 1989 it cooled sharply, making the U.S.
much cooler and wetter than Hansen had forecast, and that is likely to happen
in 1990, again. But that means that 1991 and 1992 should be warmer and
drier than usual as the El Nino current warms. It won't matter that this
has nothing to do with global warming, the media will perceive it that way,
and people will tend to believe it."

  Bernard Cohen, a physicist at the University of Pittsburgh, warns, in a
1984 book: "Our government's science and technology policy is now guided
by uninformed and emotion-driven public opinion rather than by sound
scientific advice. Unless solutions can be found to this problem, the U.S.
will enter the 21st century declining in wealth, power and influence...The
coming debacle is not due to the problems the environmentalists describe,
but to the policies they advocate."

  "Global warming" may well prove Cohen right.


By Warren T. Brookes. (from FORBES, 12/25/89)