For instance, I just ran across this interesting passage in Bill Bryson's book about the Appalachian Trail, _A Walk in the Woods_:
"... here is a thing most of us fail to appreciate. we are still in an ice age, only now we experience it for just part of the year. Snow and ice and cold are not really typical features of earth. Taking the long view, Antartica is actually a jungle. (It's just having a chilly spell.) At the very peak of the last ice age 20,000 years ago, 30 percent of the earth was under ice. Today 10 percent is. There have been at least a dozen ice ages in the last two million years, each lasting about 100,000 years....
"No one knows much of anything about the earth's many ice ages -- why they came, why they stopped, when they may return. One interesting theory, given our present-day concerns with global warming, is that the ice ages were caused not by falling temperatures but by warming ones. Warm weather would increase precipitation, which would increase cloud cover, which would lead to less snow melt at higher elevations. You don't need a great deal of bad weather to get an ice age. As Gwen Schultz notes in _Ice Age Lost_, 'It is not necessarily the amount of snow that causes ice sheets, but the fact that the snow, however little, lasts.'"
Carl Remick
-----Original Message----- From: Doug Henwood [mailto:dhenwood at panix.com] Sent: Thursday, December 10, 1998 11:45 AM To: lbo-talk at lists.panix.com Subject: Re: Earth at Its Warmest In Past 12 Centuries
Enzo Michelangeli wrote:
>For a second opinion, see:
>
>http://www.reason.org/climatefaqs.html
Cato, Reason, such lovely company the anti-warmers keep.
I loved this passage from the FAQs (drawn from risk/reward theorist Aaron Wildavsky:
>What's apparent in this anticipation / resilience framework is that it
is
>not our knowledge, but our uncertainties which most strongly indicate
the
>choice of pathway. This is because: 1) the conditions needed to assure
a
>reasonable chance of success for anticipatory actions are quite
stringent;
>2) there are more ways to get things wrong than to get them right; and
3)
>mistakes leave us less well prepared to deal with other current or
future
>problems.
>
>RPPI's research, and that of many other analysts, indicates that given
our
>current state of knowledge, we are not in a position to take
anticipatory
>action that has a good chance of producing a net increase in our
safety,
>or that of our children, or grandchildren. More research is clearly
needed
>to bring levels of uncertainty down far enough to make for reliable
>decisionmaking.
Putting this as carefully as possible, there's considerable, if not clinching, evidence of a climate change that could be absolutely disastrous for human life. But since we can't be sure, it's best to do nothing. How reasonable.
Doug