Tuesday, June 01, 2004


(Excerpts: The original of this appeared on the website of the ABC -- Australia's major public broadcaster)

"About 100 years ago (1896) a Swedish scientist made the first calculation of global warming that could be expected due to a doubling of carbon dioxide in the atmosphere. As our understanding of climate expanded through the decades of the 20th century, it became clear that a number of other gases in a planet's atmosphere act to trap radiation. Since a planet's temperature is determined by the balance between incoming solar and out-going planetary radiation, the overall effect of gases that trap radiation near the surface of a planet will be to elevate the surface temperature to a level above that which would otherwise be the case.

[ This conveniently ignores convectional cooling. The natural greenhouse effect is actually overwhelmed by convectional cooling. Alone, the natural greenhouse effect would heat the earth's surface to 75oC. Convectional cooling actually reduces it to the existing 15oC.
That is, most of the heat transfered back to space gets there via updrafts in the atmosphere, not by radiation from the surface - the greenhouse effect is purely a radiation effect. ]

Somebody coined this process the 'greenhouse effect,' erroneously likening the effect of these radiation-trapping gases to the effect of a glasshouse on a sunny day. By careful observation on planet earth, it also became clear that the comfortable temperature of the planet - averaging about 15oC - is largely due to the effect of these greenhouse gases. In the case of the earth the major naturally-occurring greenhouse gases are: water vapour, carbon dioxide, methane, nitrous oxide, and ozone where it occurs near the earth's surface.

[ Here we go with your distorting of facts. Convectional cooling dominates the earth's temperature and water vapour dominates the relatively minor greenhouse gas effect . Water Vapour causes almost all the greenhouse effect - 98% of it !! Methane, nitrous oxide, and ozone are pathetically, totally insignificant.]

This mechanism - the greenhouse effect - is well understood and its operation is accepted by even the most hardened critics of climate change.

[ And CO2 can only be a very minor and insignificant part of it. ]

The late 1950s saw a remarkable international scientific effort to understand the physical characteristics of the home of Homo sapiens. This international effort reached its zenith during 1957, the International Geophysical Year. It was during this year that high on a volcano in Hawaii, Dr Dave Keeling started continuous measurement of carbon dioxide at the Mauna Loa Observatory. The idea behind the observatory was to situate it far away from sources of city pollution, so that scientists could determine the composition of 'unpolluted' or baseline air. Even at that time scientists thought that perhaps rapid industrialisation, the burning of fossil fuels (coal, gas and oil) and deforestation might be changing the composition of the atmosphere. The ability to make such measurements required major advances in analytical technologies, because the greenhouse gases are present only in trace quantities in the atmosphere. Air contains about 78% nitrogen, 21% oxygen, with the most abundant trace greenhouse gas being carbon dioxide at 0.035%.

[ FALSE the most abundant trace greenhouse gas is water vapour it causes 98% of the greenhouse effect, (which in turn is smothered by convectional cooling), and it can be up to 4% of the air ]

In parallel with these developments, scientists realised that it is possible to recover and analyze air from bubbles trapped in polar ice. Ice core measurements have enabled us to place recent changes in the atmosphere in an historic context. Very precise records are available for the last thousand years, with other records reaching back 400,000 years.

[ If the one or two ice core experiments yet conducted are correct then the increase could simply be a natural variation. IF the ice cores coincide with industrialization it is just that - coincidence. There are other causes affecting the concentration in CO2 over the centuries and the millenia. ]

This body of research has shown, without doubt, that major greenhouse gases (carbon dioxide, nitrous oxide and methane)

[ FALSE the major greenhouse gas is water vapour - it causes 98% of the greenhouse effect - which in turn is smothered by convectional cooling. ]

have been, and are, continuing to increase in the global atmosphere. During this century a number of artificial compounds: chlorofluorocarbons (CFCs), hydrofluorocarbons (HFCs), and perfluorocarbons (PFCs), which are also powerful greenhouse gases have been introduced into the atmosphere.

[ These gases are so small in concentration that it is insulting to include them in greenhouse discussion. They cannot possibly affect it. ]

Furthermore, scientific analysis clearly shows that the combustion of fossil fuels and large-scale deforestation have driven the increase in carbon dioxide.

[ This is a plain, simple, lie. There is no science that shows that the burning of fossil fuels and deforestation is proven responsible for increased CO2, alleged to have been found in ice in polar regions. It is simple coincidence at best. The level of CO2 has always been variable in the Earth's atmosphere over the millennia. There are many other factors in play. ]


Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is to promote themselves as wiser and better than everyone else.

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