On 07/08/2019 16:11, JGD wrote:
On 07/08/2019 11:59, Spike wrote

Look what happened to that IPCC presenter chap...

Oh dear, not another one!

Another one what? Kindly explain yourself.

Why is it that the denialist fringe are so
bankrupt of ideas and arguments that their only recourse is to ad
hominem attacks on individuals.

Like the one you just made, you mean?

You seem to be in some state of confusion. I was writing in support of
the proposition mentioned earlier that scientists who go off-message
regarding CC/GW can suffer career-changing sanctions. The case I used,
which you snipped, concerned that IPCC presenter chap, who was, and
probably still is, an expert on poplar bear populations. When one
conference to which he was invited found out that his message was that
the polar bear
populations were thriving, his invitation to speak was withdrawn, and
AFAICS he has never been invited back since. But polar bears now figure
rather less in the CC publications. Others have mentioned David Bellamy,
who disappeared from our screens for being off-message. That shows how
fragile is the case for CC/GW, that such vindictive action is seen as
necessary.

Quite apart from those scientists who
are quite unjustifiably scapegoated, like any major advance in
understanding climate change also attracts its own coterie of
politicans, self-publicists and others with ulterior motives like the
anarchist tendency who seem to be behind Extinction Rebellion. But
that's life I guess.

Please let's focus on the science, not on what particular individuals -
especially those with potentially only a sketchy understanding of the
science - may or may not have said. The individuals are irrelevant, but
the science could not be more critical.

Also, while I have pen to paper: Some more distnction between primary
and secondary effects of climate change over human timescales would be
really helpful to any discussion.

Primary effects are eg:

1. Yes, global temperature is increasingly inexorably;

It's what happens when an Ice Age ends.

2. Yes, CO2 release associated with human activity seems to be the main
driver, though other gases, reduction of polar albedo etc may become
increasingly important.

....seems to be... ...may be increasingly important....

That's not science.

3. One unarguable effect of higher temperatures (barring eg a succession
of episodes of major volcanic activity) will be melting of the polar
icecaps on a human timescale, with sea-level rise and all the
consequences that brings.

I'm not sure what your scale of 'human timescale', although timescales
seem to be somewhat of a moving feast in the CC/GW industry. And it's
unscientific.

Secondary effects are all the other things like increases in extreme
weather events, changes in weather patterns for given localities etc
etc.

Weather isn't climate.

The scientific jury is still out on some of these and evidence
swinging one way and then another on some poorly-understood secondary
effect does not 'disprove' current climate change theories. (Though we
can be pretty certain that higher temperatures will bring changes to
local weather patterns (maybe the northern UK will be cooler for a while
as the Greenland icecap melts?), there will be more moisture and energy
in the atmosphere etc.)

You want to talk about science, well, here's some for you.

The Vostok ice cores showed that CO2 levels *lag* temperature levels
rather than leading them, over a time span of some hundreds of thousands
of years. Yet we are expected to believe that the lag, about 800 years,
has disappeared at some point and we now have a *lead* of CO2 over
temperature. When was the tipping point? What was the mechanism that
flipped lag to lead? Remember that human activities have added only a
minuscule amount of CO2 to the atmosphere.


--
Spike