On Mon, 25 Jan 1999, Michael S. Lorrey wrote:
> If it is a human virus that is killing the coral, then its likely brought
> there by the divers who protest about the coral's destruction. However, I
> have also seen studies (don't have any cites handy) which assert that much of
> the coral die offs is a natural cyclic occurence, as they grow too close to
> the surface for the species present, or for other reasons.
If one examines the fossil record, corals historically are the hardest hit during climatic changes. Their diversity and abundance has fluctuated dramatically through time.
> b) the ozone hole lets in too much UV which kills plankton. While too many
> people equate the ozone hole (caused by CFC aerosols, mostly) with global
> warming, they are, in fact, two entirely different phenomena. Since the
> amount of CFCs being released world wide has dropped dramatically, and
> continues to decrease, climatologists now consider the problem of the ozone
> hole almost solved, it just will take time for the CFCs currently in the
> stratosphere to reduce (about 10-20 years) to more natural levels. At that
> point plankton levels should be rebounded handsomely.
CFC usage has been dramatically reduced only in most developing nations
(although there is a substantial black market I hear).
In developing nations, CFC's are still widely used in vast amounts.
Furthermore, a lot of these CFC's used by developing nations are
manufactured in North America! AFAIK, It is still legal to produce them,
just not to use them.
I've also read that the alternative coolants used in CFC-free countries are
almost just as detrimental to the ozone and general environment as CFC's!
It doesn't sound to me like the ozone hole will be getting any better for a long time to come (unless we develop and deploy a method of mopping up all the CFC's in the stratosphere)
--Aaron
+-----------------------------------------------------------------+ | Aaron Davidson | ajd@gpu.srv.ualberta.ca || Silicon Creek Software | http://ugweb.cs.ualberta.ca/~davidson/ |
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