Re: Cycling not related to global warming

On 20 May 2007 03:26:27 -0700,
raisethe <raisethe@xxxxxxxxxxx> wrote:
On 20 May, 01:57, John Kane <jrkrid...@xxxxxxxxx> wrote:

I agree here but what we have is a visible warming of the climate
scientifially and anecdotally ( I don't know about the UK but where I
live in Canada it is easily observed over a lifetiime [mine ]) and the
science predicts almost exactly what a naive observer sees.



If I might offer another note of sceptism.

When you invest in shares one of the first bits of advice you get is
that you should be very cautious about using past performance to
predict the future yield. If global temps have been rising for the
past 30 years, it is easy to extrapolate this to show how much they
will rise in a further 30 years. However, they could just as well be
peaking and we could be heading toward another cold period.

No. You have to have a model that explains why the temperature is rising
that also allows for it to peak and start to fall.

Back in the 40s there were two significant effects, increase of sulphate
aerosols and increase of CO2. There wasn't enough quantitative data to
predict which would dominate, even as late as 1976 peer reviewed papers
basically said "aerosols make it colder, CO2 makes it warmer." Some said
"If we continue increasing aerosols at the rate we have been then we
could end up in an ice age."

By 1980 it had become obvious that the CO2 warming would dominate.
Additionaly, sulphate aerosols haven't continued to rise, infact, they
have fallen after the observed problems that acid rain was causing
caused factories and powerstations to clean up their (aerosol) acts.

It is possible that CO2 driven warming has now peaked and it won't get
any warmer. Certainly each additional 1% increase in CO2 causes less
warming than the previous 1%. (Personally I think this is very unlikely)
But for temperatures to start cooling again you've got to have something
that can cause that cooling and there doesn't seem to be anything at
all. Even assuming we are now heading into a natural ice age we're
talking kiloyears at least. It will take centuries of data at least to
be able to show a cooling trend in the natural noise.


The fact that we can measure climate change at all in a lifetime,
whether that be aerosol cooling in the 40-70s or CO2 warming now should
be really frightening. Climate just doesn't change on the length of a
single life of any animal. Local weather yes, but not climate. And now
man has managed to swing it both ways. If you keep rocking the boat
hard, eventually it will capsize.


Tim.

--
God said, "div D = rho, div B = 0, curl E = - @B/@t, curl H = J + @D/@t,"
and there was light.

http://tjw.hn.org/ http://www.locofungus.btinternet.co.uk/
.

Relevant Pages

  • Re: Global warming hoax
    ... Did you notice how current CO2 levels are higher than at any other ... temperatures will become higher than is ... ancestors must have survived similar changes in climate. ... would have been warming. ...
    (comp.sys.mac.advocacy)
  • Re: Global warming hoax
    ... It looks to me like there is a 100,000 year cycle of warming ... Did you notice how current CO2 levels are higher than at any ... temperatures will become higher than is ... ancestors must have survived similar changes in climate. ...
    (comp.sys.mac.advocacy)
  • Re: global warming: is it us, or is it the sun?
    ... A temperature rise on such a scale, in a foreseeable future, ... screening sunlight with aerosols. ... further warming now) that failed to materialize. ... || Climate," the paper examined the possible future effects ...
    (sci.space.policy)
  • Re: Israeli Scientist Changes Sides On Global Warming
    ... Step Three No other mechanism explains the warming. ... I was personally sure that CO2 is the bad culprit ... in the story of global warming. ... Panel on Climate Change-- the United Nations agency that heads the ...
    (soc.retirement)
  • Re: Stolen honor.
    ... global warming as well. ... Scientists who conclude that the observed warming is more likely ... but in 2006 he joined a climate skeptic ... increasing CO2, which is in fact a minor greenhouse gas, triggers a ...
    (rec.boats)