On 18 Feb 2003 18:00:46 -0800, (Scott Murphy) wrote:

Larry Caldwell wrote in message t...
(David Ball) writes:

Jesus Murphy! Would you two kindly do a little thinking,
especially about the meaning of cause of effect. The fires were CAUSED
by lightning or a careless camper or god-forbid...a MATCH! Think about
it! Global warming is an effect. It cannot CAUSE anything. In the case
you speak about Larry, the fire load in the forest EXACERBATED the
fires, but it sure as hell did not cause them. Long periods of dry
weather can EXACERBATE the fire situation, Alistair, but it does not
CAUSE the fire in the first place. Fire load and dry weather are
contributing factors to the extent and severity of the fire, but they
are not, EVER, the cause.

You have a pretty narrow version of causality there, David. If forest
fires are caused by lighting or carelessness, why don't we have forest
fires in the winter?

Would it help if the discussion was framed in the context of 'risk'
and 'hazard', where 'risk' is the probability of ignition (e.g.
lightning or 'the match') and 'hazard' is the fuel condition or state
that MAY lead to a fire?

How might global warming affect risk and/or hazard?

Definitely!! GW will increase the risk...possibly. GW will
alter weather conditions on most scalesy, so it is very difficult to
speak in anything other than broad terms.


Which combination of hazard and risk is likely to be most prevalent
given the effects of global warming?

1)high risk, low hazard
2)high risk, high hazard
3)low risk, low hazard
4)low risk, high hazard

What are the effects of low intensity (low hazard) fires that occur
frequently (high risk)?

What are the effects of high intensity (high hazard) fires that occur
frequently?

What are the effects of low intensity fires that occur sporadically
(low risk)?

What are the effects of high intensity fires that occur sporadically?

Finally, what would a landscape with such a fire regime look like
(ecologically as well as aesthetically), and how would such a fire
regime affect human activities (e.g. where houses get built, forest
management practices)?

As I said above, speaking with any kind of certainty is
impossible at this time. We can make broad statements about what might
happen, but they have to remain broad. My pet-peeve is with people
attempting to blame GW for everything from the snow in the eastern US
the past few days to the forest fires last summer in the American
west. While we can make statements about possible or even probable
impacts of GW, we simply can't blame each and every event on it.