These global warming signs confuse me a bit. If the temps have changed by less than a degree (or whatever) on average, how would that explain unseasonably warm temps during one summer, as well as droughts and such. Why would warmer temps even mean drought? I’m not a climatologist, obviously, but I thought we were told that simply seeing higher temps one year (or lower temps) in a particular area didn’t prove or disprove global warming, which is more subtle, really.
There is unrest in the forest
There is trouble with the trees
For the maples want more sunlight
And the oaks ignore their pleas
The trouble with the maples
(And they’re quite convinced they’re right)
They say the oaks are just too lofty
And they grab up all the light
But the oaks can’t help their feelings
If they like the way they’re made
And they wonder why the maples
Can’t be happy in their shade
There is trouble in the forest
And the creatures all have fled
As the maples scream ‘Oppression!’
And the oaks just shake their heads
So the maples formed a union
And demanded equal rights
‘The oaks are just too greedy
We will make them give us light’
Now there’s no more oak oppression
For they passed a noble law
And the trees are all kept equal
By hatchet, axe and saw
This (first four minutes) probably doesn’t answer your question but it’s a good talk on the subject in general, but the effects I’ve never heard described as subtle. Supposedly, small changes in temperature can have dramatic effects. From your link, it’s not really a matter of proving global warming, more as given they data they have, global warming seems like the most reasonable hypothesis.
No, it’s a matter of the far reaching impact of temperature directly on weather systems, not the kind of half domino / half chaos effect that people usually associate with the butterfly effect. Like in the first four minutes of that video, the earth was only on average 6 degrees colder and we were in an ice age.
Scientists say forests in the Western U.S. have been increasingly damaged in recent years by invasive insect species such as the bark beetle – a sign that rising temperatures are having an adverse effect. Bark beetles are known to attack trees already weakened by other environmental factors.
“Many of these beetles cannot survive in cold temperatures, and it’s getting warmer,” said Tim Barnett, a *research marine physicist at Scripps Institution of Oceanography at the University of California, San Diego. Barnett authored a research paper linking drought conditions in the American West to increased human activity.
Here in BC those beetles are killing A LOT of the trees. Normally, their hibernating eggs/larvae would be killed off in the cold winters but in the past several years the winters have been rather mild. Thus, the beetles are surviving and moving west to east and northwest to southeast.
[B]Q. When will this epidemic end?[/B]
Severe prolonged cold weather or a loss of host trees is the only way to stop the spread of mountain pine beetle. In the Cariboo-Chilcotin, the infestation in the early 1980s continued for ten years, before this weather pattern reduced the spread of mountain pine beetle.
I promise to post about this when I get time. I think I can answer most of your questions. I have a BS in biology, where I concentrated in Ecology and Environmental Science.
