From: brian@quake.sylmar.ca.us (Brian K. Yoder)
Subject: Re: Sierra Club on Herschensohn
Organization: Quake Public Access
Distribution: ca
Date: Sat, 7 Nov 1992 07:08:27 GMT

In article <1d6lqeINNdee@agate.berkeley.edu> map@violet.berkeley.edu (Pollen Lab;103 ESB;38108;2335707;NZ29) writes:
>In article <Bx2JpG.478@quake.sylmar.ca.us> brian@quake.sylmar.ca.us (Brian K. Yoder) writes:
>	{various quotes from Herschensohn deleted}

>>>	o Has said, "I don't believe in global warming or a hole
>>>	  in the ozone layer"

>>I don't either, and neither do a lot of scientists (even "most" scientists
>>depending on how you count the numbers).

>I'm getting increasingly annoyed by how often I hear statements like the
>above--and the fact that Herschensohn may become a U.S. senator today is
>not the only reason for my annoyance.

>My research is on the impacts of climate change on forests in the Sierra
>Nevada.  I'm studying what happened 10,000 years ago, but I have done a
>lot of reading on the greenhouse effect, and on stratospheric ozone.
>I would like to strongly contradict Brian's statement, as follows.

>ALL reputable scientists accept as facts that:

>1. There is an atmospheric "greenhouse effect" which traps long-wave
>radiation and increases the earth's surface temperature, and the
>concentrations of gases like CO2 and CH4, which are known to selectively
>absorb long-wave radiation, have been increasing during at least the
>past century as a result of human activities.  

Actually, there is some dispute about the degree to which this increase is
due to human activity, but it is generally agreed by all sides that CO2 levels
are increasing.

>Climatic changes will
>occur as a result of these human-induced changes in the earth's energy
>budget.  

That is not generally agreed upon.  There are doubts as to the extent of
human involvemnt and the scope of the changes, as well as even the long-term
direction of those changes.  Empirical evidence doesn't bear out your 
position either.

>At present, there is significant scientific uncertainty as
>to the nature of those climatic changes, particularly where, when, and
>how much temperatures will increase, and how precipitation
>and clouds will change.

As well as IF the temperature will increase or decrease, and whether the
sea level will rise or fall (for example, if slight warming increases
evaporation, it might beef up water vapor sinks (like the polar ice caps)
which over time might lower ocean levels.

All that aside though, as a POLITICAL issue, when someone (like Al Gore for
example) says that we have to change the fundamental purpose of civilization
in order to prevent the consequences of global warming, that is NOT warranted 
based on the scientific facts, and that's what Herschensohn and I are talking
about.  The alarmism afoot in the political realm is unwarranted by the
scientific evidence.  Have you read the Heidelberg appeal signed by all those
Nobel prize winners?

>2. The atmospheric concentration of ozone (which selectively absorbs
>incoming ultraviolet radiation) has been decreasing, particularly in
>the last 10 years or so.  

Ummmmm, I was unaware of any direct evidence of that kind.  Where did you hear
that? How do you explain the lack of increase in the level of UV reaching the
ground in light of this? 

>More importantly, during the southern hemisphere
>spring (October- November), an "ozone hole" develops over Antarctica.
>This hole did not occur in the late 1950s, 

My understanding is that Dobson made som measurements in the late 1950's (which,
if memory serves, he considered anomalous) whic showed an ozone hole then too.

>but by the late 1980s,
>about 70% of the total ozone over Antarctica was lost each spring.

...and replenished again after a few weeks.  There are plenty of respectable
scientists who doubt that there is a link between ozone and anthropogenic 
chlorine compounds.

>>I do.  I just don;t think they are "frightening".  They are quite sensible, as
>>are most of his other views (aside from his anti-abortion stand).

>Those are scientific *facts*.  As a scientist, I think there is a need
>for debate on the appropriate responses to these global environmental
>problems, and there is also a need for further research.  However, 
>I think it *is* "frightening" and irresponsible when people like
>Senate candidate (let's hope that's all) Bruce Herschensohn denies
>that the problems even exist.

What about when scientists deny that they exist?  If you think there are
none, I can post some long lists of them, and we can (yet again) run down
the various bits of evidence for each side.  To claim that the scientific
case is closed is ludicrous.  It is also wrong to assume that the proper
means for dealing with such problems as do exist, by dismantling 
industrial civilization or violating people's rights.

I'm curious, your signature says you are a geographer.  Why do you think that
gives you such great qualifications in the area of climatology and 
atmospheric chemistry?  Of course, I'm not one of those who insists that
nobody should comment on areas outside his specialty, but you seem to be
using the old "I'm a scientist therefore your arguments are false." rhetoric.

--Brian