The earth is presently at a climatic high point, that in the last 25 million years or so temeperatures have only exceeded what we are experiencing now for about 2% of the time.
Global temperatures during the holocene ( about the last 15000 yrs) have actually dropped a few degrees, between 15 and 10 thousand years ago, the temperature was a couple of degrees higher and the subsequent sealevel rise can easily be seen as a fossilised "beach behind a beach" almost anywhere in the world.
I think what a lot of people dont understand is the complexity of climate. For example: Global warming could in just a couple of months cause a mini ice age in western europe that would have catastrophic effects on agriculture and the economies that depend on them.
I am talking about an ocean current called the "Atlantic Conveyor". Most people are familiar or at least have heard of the gulf stream, a large current that takes warm tropical water across the north atlantic and arrives off the coast of ireland and scotland. Most people dont realise that there is another current that pretty much follows the same route, but goes in the opposite direction and is at the bottom of the ocean, not the top. This is because warm water rises to the top and when it dumps its energy in europe, it sinks to the bottom and goes back where it came from. Forming what looks pretty much like a conveyor belt in the ocean (hence its name).
In the event that we have a particularly warm year, there would be heavier precipitation in the form of snow in baffin bay and the arctic ocean, the resulting ice could then move further south than normal, then when it reaches the place where the Titanic met her fate, it will melt.
Now, sea ice desalinates itself after a couple of years (about four I think) and we all know that fresh water sits on top of salt. This would create a large lens of fresh water, wedging itself into the gulf stream that could in a matter of weeks not only divert the gulf stream, but stop it as effectively as a broken track will stop a bulldozer.
If the gulf stream were to stop today, the temps in europe would drop by at least 5 degrees or so. Forget about wine from france or beer from Germany, those crops will fail.
We know this has happened before; anyone that has read Charles Dickens knows that London is always snowy and cold right?? By coincidence around about the itme he was writing about the snowy south of England, uncle scrooge and oliver twist, there was a potato famine in Ireland and widespread agricultural failure in much of the rest of Europe, which in a large part resulted in an exodus of starving Europeans to north America. This we think was the last time the conveyor was stopped.
How and why it stopped and restarted back then, no one knows.
Now, I am not saying it will happen, but I am saying it could happen and it could happen in just a couple of weeks from now as we enter the northern spring..
Climatology is like any other science, you cannot predict what will happen, but you can predict the probabliity of something happening and this holds true whether you are discussing the movement of galaxies or subatomic particles....
......or whether we need to undo some of the damage we have done to the earth, and this particular case its climate, over the last few hundred years since the beginning of the industrial revolution. I believe the Kyoto Accord, whether you think it is effective, fair or not, is a symbolic gesture that says that 143 countries agree with this.
I also think that where a large part of the trouble starts, is when one particlarly large contributor to greenhouse gasses and user of the worlds natural resources (which will remain anonomous but lies somewhere between Canada and Mexico) returns this global goodwill gesture with a guesture of their own which pretty much involves the middle finger of one hand..
Just my 2 cents
