Date: Fri, 07 Nov 1997 04:06:37 -0500
From: Siddharth Chatterjee <siddhart-AT-mailbox.syr.edu>
Subject: M-I: Global Warming


>From Jay Hanson's page:

>  Present-day society is locked into four positive feedback loops which
>   need to be broken: economic growth which feeds on itself, population
>      growth which feeds on itself, technological change which feeds on
>      itself, and a pattern of income inequality which seems to be self
>    sustaining and which tends to spur growth in the other three areas.
>       Ecological humanism must create an economy in which economic and
>       population growth is halted, technology is controlled, and gross
>            inequalities of income are done away with. —Victor Furkiss,
>                              THE FUTURE OF TECHNOLOGICAL CIVILIZATION
> 
> ----------------------------------------------------------------------
> 
>                  An Example of the Catastrophic View:
>                       A Global Warming Scenario
> 
>                 ECOLOGICAL DEMOCRACY, by Roy Morrison;
>               South End Press, 1995; ISBN 0-89608-513-9
> 
> In 1992, Dr. Jeremy Leggett, a British scientist and scientific
> director of Greenpeace International's Atmosphere and Energy Campaign,
> outlined what may be called a "nightmare global warming scenario."
> This scenario was based on a projection of known, but as yet
> unquantified, biological feedback mechanisms identified by the
> Intergovernmental Panel on Climate Change (300 atmospheric scientists
> from forty countries).
> 
> This scenario is a plausible extrapolation from what is known: it
> reflects both the magnitude of the possible risks courted by
> industrial humanity, and the inadequacy of the global managerial
> perspective when circumstances go beyond what is viewed as
> industrially acceptable. However, even if this scenario is completely
> accurate, industrial managers can always point to enough uncertainty
> at each step to justify inaction.
> 
> Global warming is the result of the release into the atmosphere of
> "greenhouse gases," i.e., gases that are relatively transparent to the
> passage of energetic short-wave solar radiation (sunlight) and, at the
> same time, reflect back much of the longer wave infrared (or heat)
> radiation generated when sunlight strikes the earth. The most
> significant greenhouse gas is CO:, which has been released into the
> atmosphere in huge quantities as a by-product of burning fossil fuels
> in automobiles, power plants, and industrial processes such as steel
> production, and by wood burned for fuel and forests burned for
> land-clearing. In 1950, 1.62 billion metric tons per year of carbon
> (gigatons carbon or GTC) were released from burning fossil fuels; by
> 1991, this figure had increased to 5.854 billion tons per year.
> 
> To get some sense of the significance of this number, we need to know
> that the preindustrial atmosphere contained an estimated 580 billion
> tons of carbon. Thus, we are now adding about 1 percent of the
> preindustrial carbon total to the atmosphere yearly. Current
> atmospheric carbon levels are 750 GTC, a 29 percent increase from
> preindustrial levels. In only thirty-two years since 1959, when
> continuous record keeping of atmospheric carbon dioxide began,
> concentrations have increased 12 percent from 316 parts per million
> (.0316 percent) to 355 parts per million (.0355 percent). Other
> greenhouse gases include methane (CH4), a product of natural decay and
> fermentation released in large quantities from concentrated livestock
> production, and the chlorofluorocarbons (CFCs) that are also
> responsible for the destruction of the ozone layer.
> 
> The precise global dynamics and possible effects, both long-and
> short-term, of huge increases in greenhouse gases are unclear. There
> is a natural cycle that keeps CO2 concentrations relatively balanced.
> Huge amounts of CO2 are dissolved in the oceans, 39,000 GTC with about
> 90 GTC exchanged each year between atmosphere and ocean. (CO2 in water
> forms carbonic acid-this is why steam heating condensate pipes often
> corrode unless the boiler water is deaerated.) Huge amounts of carbon
> are also locked up in submarine methane hydrates, ice-like solids made
> up of water crystals and trapped methane gas, on the Arctic
> continental shelf.
> 
> Carbon is also found in the bodies of all living things, from giant
> redwoods to microscopic creatures (an estimated 750 GTC in land plants
> and 1,500 GTC in soils; annually 100 GTC is exchanged between the
> atmosphere and land plants.) The normal carbon-based system includes
> the use of CO2 by plants, which release oxygen as a by-product that is
> then used for animal respiration (which, in turn, yields CO2 as its
> by-product). The carbon taken up in the bodies of living creatures is
> also released in the form of methane as they die and decay.
> 
> Atmospheric scientists argue that climate stability can likely be
> sustained if levels of human CO2 production are somewhat below the
> emission levels seen in the 1950s. At present rates, by the middle of
> the 21st century, most climate scientists predict substantial
> increases in global temperature.
> 
> How significant these increases will be, and the nature of their
> impact, is the question. Jeremy Leggett warns that such global warming
> may disturb major sinks for carbon in Arctic tundra and, through a
> complex series of interactions, result in runaway warming that would
> continue even if human CO2 and all other greenhouse gas emissions
> dropped to zero.
> 
> Leggett's "putative" logical chain of events includes:
> 
> As the oceans warm, they are less able to absorb CO2.
> 
> Warming oceans are more thermally stable. This stability reduces the
> circulation of nutrients and decreases the biomass of the
> photoplankton, thus further damaging the ability to absorb CO2.
> 
> Ultraviolet radiation from the damaged ozone layer, particularly
> severe in polar regions, further damages the photoplankton. The net
> ecosystem balance between respiration (CO2 emitted) and photosynthesis
> (CO2 used) now tilts toward respiration, and more CO2 is released into
> the atmosphere.
> 
> As the temperature rises, Arctic tundra melts and releases huge
> amounts of methane. Under certain conditions, wet, flooded soils can
> release 100 times more methane than dry soils.
> 
> At this point, drought in many areas from warming and associated
> climatic changes further retards photosynthesis.
> 
> Changes in the chemistry of the atmosphere deplete the cleansing
> hydroxyl reservoir that oxidizes methane and other greenhouse gases.
> 
> Ozone in the troposphere, a greenhouse gas at lower levels of the
> atmosphere, is increased as a result of carbon monoxide and nitrous
> oxide from growing automobile exhaust.
> 
> The Arctic ice cover begins to thin and retreat. This thinning reduces
> the albedo (the net reflectivity of the planet), thus leading to
> further warming.
> 
> Finally, huge amounts of methane trapped in the Arctic continental
> shelf in the form of methane hydrates are released from under the
> permafrost and in shallow Arctic waters.
> 
> Leggett concludes, "In emergency session the UN brings in sweeping
> measures for world-wide greenhouse gas emission reductions. But it is
> too late. A runaway greenhouse effect has been generated."
> 
> This chain of events is a dark possibility. It is not a prediction. It
> does make clear that industrial civilization has put into question not
> just the prospects for human society, but planetary processes hitherto
> the domain of natural rhythms and geological time. Industrialism is
> betting that its resolute commitment to continuous growth can somehow
> be managed to avoid catastrophic consequences.
> 
> The world has 4,000 GTC in proven fossil fuel reserves; we cannot
> decide their future use, the production of further CFCs, and the mass
> burning and clear-cutting of forests on the basis of maximizing
> industrial production and consumption, profits and power. Industrial
> civilization entertains a hideous risk if it continues each year to
> pour 5.8 billion tons or more of carbon into the atmosphere. Whether
> industrialism's technocratic eschatologies are reassuringly
> exponential, cautiously logistic, or righteously catastrophic, social
> behavior, as well as the reality behind imperfect mathematical models,
> will determine the nature of alternative futures. [p.p. 109-112]
> 
> ----------------------------------------------------------------------
> 
>                   POSITIVE FEEDBACK THROUGH SYNERGY
> 
> LONDON, Feb 21, 1996 (Reuter) - Global warming, acid rain and the hole
> in the ozone layer are joining forces in a deadly combination for fish
> and other life in lakes and streams, Canadian scientists reported on
> Wednesday.
> 
> The key, they said, was the amount of carbon dissolved in the water.
> Carbon absorbs ultraviolet radiation from the sun, and protects
> aquatic plants and animals from the dangerous solar rays being let
> through by the widening holes in the ozone layer.
> 
> But the researchers said global warming and acid rain were reducing
> carbon levels in lakes, thus wiping out what little protection the
> fish and the plants they depend on had.
> 
> Acid rain is caused when clouds pick up pollutants such as sulphur
> dioxide from factories and coal-burning power plants. The chemicals
> react and raise the acidity of the rain.
> 
> David Schindler, a biologist at the University of Alberta in Edmonton,
> and colleagues took measurements at several lakes in northwest Ontario
> over 20 years.
> 
> During this time, Schindler's group wrote in the science journal
> Nature, overall temperatures rose by 1.6 degrees C (1.9 degrees F),
> rainfall fell by 25 percent and "once-permanent streams became
> intermittent."
> 
> Carbon levels in the lakes fell by 15 to 20 percent, allowing
> radiation to penetrate 22 to 63 percent deeper.
> 
> In the lake with the highest acid levels, ultraviolet radiation
> penetration increased from a third of a metre (one foot) to more than
> 2.8 metres (nine feet).
> 
> "An 80 percent decline in carbon, as in acidified lakes, would cause
> the depth of the...UV-B...to increase by over 400 percent," they
> added.
> 
> Radiation is as dangerous to fish and seaweed as it is to people and
> their crops. For example, trout get sunburn, are more prone to fungal
> infections and in general die sooner when exposed to slightly higher
> radiation levels.
> 
> Extra radiation could become one more stress that pushed a species
> over the edge into extinction, they said.
> 
> "Overall, we estimate that about 140,000 of the nearly 700,000 lakes
> in eastern Canada may have (carbon) concentrations low enough for UV-B
> penetration to be of concern," they said.
> 
> ----------------------------------------------------------------------
> 
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