[Coral-List] ice-ages vs warming
Charles.Sheppard at warwick.ac.uk
Sun Dec 20 04:10:02 EST 2009
Someone asks older coral list folk how much of a consensus there was in those far off olden days on ice age development. I suppose Im one of those who remembers things from way back in the Plio-eighties...
There was an intriguing hypothesis (which the media jumped on as being scary fact of course). The details I heard in the 1980s went as follows, and will confuse some further:
1. Things were warming and winds would strengthen too,
2. Leading to greater evaporation from oceans.
3. What goes up must come down, and a proportion of the 'down' would, as always, be over the poles.
4. Poles are at an average temp of minus something (let's say -10 degrees for the current purpose)
5. Even though the poles will warm a degree or so, even minus nine means frozen solid, so:
6. That which comes down in polar regions will still become locked up as ice.
7. So, some of the buzz way back then was that a slight warming globally might lead to a spread of the ice sheets to lower latitudes as more and more ice accumulated at the new minus nine (or whatever the actual minus value was).
i.e. warming leads to expanded ice caps, leading to changed global albedo etc etc. Naturally that is too complicated for British tabloid newspaper readers (I wouldn't be so rude as to comment on other Nation's tabloid readers). But if an editor sends a camera crew somewhere nice and wintery, preferably with an old lady or two struggling into the snow-laced wind with shopping bags and a sad expression etc, he can convey suitably excitable thoughts.
I remember discussing these 'water balances' with colleagues in the summer in a mid-eastern desert country where there had been no rain for about 2 years! There was talk around then too of towing icebergs to the middle East, to supply cubic km of fresh water...
Professor Charles Sheppard
Dept Biological Sciences
University of Warwick
Coventry, CV4 7AL,
charles.sheppard at warwick.ac.uk
tel (44) (0) 2476 524975
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