JohnM, the issue is not a political one, though it's been politicized, but a scientific one.
Several facts are well known and cannot be disputed. First, weather patterns operate on an exceedingly long time line. Secondly, greenhouse gasses, particularly carbon dioxide which is associated with human activity, are known to be concentrating in amounts that exceed those that might otherwise be found. It is a scientific fact that CO2 takes a long time for the biosphere to process.
When one takes into account long-term weather patterns that might account for warming and cooling, it becomes very difficult to say that excess greenhouse gasses are causing warming in excess of that which might occur naturally, without human intervention. There is some evidence that they might induce substantial cooling instead of warming.
I have not seen anything that convinces me that there has been warming caused by greenhouse gasses. Volcanos and other natural phenomena make it a devilishly difficult thing to measure and prove.
On the other hand, greenhouse gasses, particularly CO2 and water vapor, are by definition heat-entrapping. Carbon dioxide has been absolutely positively proven to have reached concentrations that exceed by far the concentrations that were prevalent before the Industrial Revolution.
Since greenhouse gasses have the potential for warming up the earth more than might otherwise occur, it's probably a very good idea to limit these gasses despite the lack of scientifically reliable proof that they play a part in current alleged earth warming, particularly since some of them require a long, long time for the biosphere to process.
Nonetheless, to claim that greenhouse gasses have been absolutely positively proven to cause present earth warming is complete politicized hogwash. They may very well be, but rigorous scientific proof is lacking because the issue is presently too scientifically complex.
Beware of any politico who claims otherwise, though I think that the exercise of sound policy judgment requires us to limit greenhouse gasses to the extent we can. |
