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Originally Posted by classicman
or maybe the period of time which we have measured is so historically insignificant that our data is equal to no more than a "sun fart."
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It is true that our written records are very short, but analysis of tree rings (especially of oak preserved in peat bogs for thousands of years), the rings of coral growths, the layers of ice (and the bubbles trapped in ancient ice) and ocean and lake sediments, all combine to deliver a record stretching back much much further.
(You might argue about the interpretations placed on each of these, of course. What follows presumes that these records are reasonably accurate.)
The record they deliver does indicate that climate has been wobbling all over the place for at least the last 300,000 years. There is no "correct" or "stable" global climate that Earth is "supposed" to be at. Nevertheless, the earth is much hotter now than it has been for a long time.
Quote:
Originally Posted by classicman
Did/is something happening? yes are we responsible - no one knows. its a pointless issue to raise. 30 - 40 years ago we heard about global cooling, not its warming - nothing, NOTHING says it isn't perfectly normal and caused by the natural order of things.
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The fact of change is not abnormal. The
rate of change is entirely unprecedented in the last 300,000 years. Likewise the rate of increase of CO2 (also lead, CFCs, etc etc) is also unprecedented.
These unprecedented rates of change indicate that human activity is probably the cause. Change is natural, really fast change is not.
Natural or not, ask yourself: do you want big climate change? In the short term: more and bigger storms, hurricanes, etc? Heatwaves killing more people? The spread of mosquito borne diseases? We are (perhaps) seeing some of these now.
In the middle term, sea-level rise? Land lost to this? Widespread extinctions as animals are unable to adapt to the changes in climate?
I'd prefer that these things not happen, not just for my future self but as a general responsibility to the future people of our civilization.
If we are the cause of it (and a solid majority of scientists agree that we are) then we ought to stop doing the things that cause it, and start undoing them.
Even if we aren't the cause, we still ought to see what we can do to reduce and mitigate the effects.
[Texan] Are you wit' us or are you agin' us? [/Texan]