What is Global Warming?
The topic of Global Warming has been in the news for a
number of years, so it is appropriate to be certain that a clear, simple
explanation is available. Global warming is, in plain terms, the increase in
the average temperature of the Earth, in particular the surface, water, and
atmosphere.
Global warming is usually attributed to three possible
factors: heat produced by the Earth itself either as a result of radioactivity
or gravity; increases in solar radiation; or the greenhouse effect, which is
the trapping of infra-red radiation from the surface and atmosphere by gases in
the atmosphere. Measurements of the intensity of solar radiation have been
constant for at least the last 30 years, so global warming for that period
cannot be attributed to solar energy. Periods of sunspot minimums, such as the
Dalton Minimum during the late 18th and early 19th century , have
resulted in periods of unusually cold weather due to reduced solar radiation. In
fact, evidence is that we are in the first decade of another solar minimum,
despite the continued rise in average world temperature. The internal sources
of heat seem to have been constant for many millennia (actually eons ).
The greenhouse effect has been studied by scientists since
about 1820, when Joseph Fourier first studied it. Famed scientist and engineer
Alexander Graham Bell warned of the dangers of heavy reliance on carbon based
fuels for power as early as 1917. He noted that increases in the levels of
carbon dioxide could result in global warming due to the greenhouse effect. He
advocated for alternate energy sources such as solar energy. He actually invented the term global warming.
Since the time of Alexander Graham Bell there has been
considerable study of the effect of burning non-renewable carbon fuels for
energy production. The topic remained primarily of modest public debate until
recently, perhaps gaining interest primarily after politicians such as Al Gore
began to bring it into the mainstream.
The main source of new carbon dioxide is the burning of
fossil fuels such as coal, gas, and natural gas by humans, but deforestation
accounts for over 20%. Other significant types of significant green-house gases
are chlorofluorocarbons (such as freon ) and methane. Chlorofluorocarbons are
being reduced as a risk by vastly reduced use of them. Methane poses a threat as global warming
thaws frozen tundra and heats Arctic lakes, resulting in significant methane
release.
About 10,000 years ago underwater landslides caused a
massive release of frozen methane and may have caused a sudden acceleration of
global warming. The flooding of the Black sea, which may have occured as a result of the breaching of the Bosporus strait by rising water in the Mediterranean, is the putative source of the Gilgamesh/Noah flood story. Some scientists warn of the potential of such landslides off
the East Coast of the United States.
Rice farming and cattle breeding also
produce methane, as do sewage plants and land-fill s . Many sewage and land-fill
facilities either burn or collect methane to convert into fuels. Both processes
result in eventual release of carbon dioxide. Methane, however, is much worse as
a greenhouse-gas.
Man caused (anthropogenic) global warming nay-sayers have
not quite yet been classed along with flat-Earthers, but the resistance to the
concept is fading, shifting more and more to the fringe. One website complains
that Vice-President Gore "forecasted" that there would be total
melting of Arctic sea ice by 2013. Besides making up words, they also proceeded
to claim that polar ice at both poles has increased, which is totally a
fabrication. Both poles are undergoing well documented rapid loss of ice. The
surface area of sea ice in the Antarctic region has increased due to the
refreezing of some of the run-off from the melting continental ice pack and the increased movement of glacial ice into the ocean, but
the total amount of ice has decreased.
This has resulted in added confusion among the scientifically illiterate
deniers.