On or around Wed, 01 Nov 2006 17:55:32 GMT, "Cyberwraith"
<jfnfy4evr@ntlworld.com> enlightened us thusly:
>
>I am no scientist but I agree with the natural cycle idea. There was a
>documentary sometime last Christmas talking about the Gulf Stream and how it
>is actually cooling. However they said there is evidence that it does this
>on a cycle. OK a very long one possibly millions of years each way. If all
>transport was stopped until clean could be allowed out of the safes that the
>petrol companies keep it all in that would be one way. Picking on a minority
>group is just hype, and greed.
>
The gist of the thing is not that the level of global warming is unusual or
unprecedented, but that it's happened in what in geological terms is a split
second. The normal sort of climate changes take many hundreds or thousands
of years, although significant events such as Krakatoa or Mt St. Helens can
have a measurable effect.
The comment about grape vines, for example: The Romans were growing vines
about 2000 years ago, the Thames was known to freeze a few hundred years
ago. There's a certain amount of evidence that we are in fact in a minor
ice age, bar for the effects of man.
however, it's nowhere near as clear-cut as everyone thinks. For example:
global warming results in more water vapour in the atmosphere (and water
vapour is a good greenhouse gas); but! water vapour in the atmosphere leads
to more clouds, which lowers the albedo.
And so on. It's all a very big interlinked system, wherein small (in global
terms) changes can have far-reaching and (partly) unpredictable effects.
There's a good chance that we've already altered the climate beyond a
critical no-return point: large areas of Tundra are about to melt, which
will release large amounts of greenhouse gases...
However, there's another aspect to this - the doom-and-gloom types
predicting the end of life as we know it might have it right, but that
doesn't necessarily imply the end of life on the planet. Things will
change, animal populations will move, temperate crops that used to grow in
one place will grow instead somewhere else and the places that used to grow
those crops will grow tropical stuff. Large areas which have been too cold
to grow anything much will become cultivable (the aforementioned tundra, for
example). Some species will probably go under due to inability to react,
and others will come along to replace them. One thing it will be is
interesting...
--
Austin Shackles.
www.ddol-las.net my opinions are just that
"Would to God that we might spend a single day really well!"
Thomas À Kempis (1380 - 1471) Imitation of Christ, I.xxiii.