BattleMoose wrote:... Classically the opposition you may run into is the objection that this is just correlation and on the face of it its a fair objection, having two things correlated does not mean there is any causation. Any random unrelated things may be correlated beautifully.
There also needs to be a hypothesis/theory that explains the correlation and of course there is with global warming a very good one and these charts are a very important aspect of our understanding of global warming.
Actually, understanding why the population and GHG charts are correlated goes a very long way to understanding the skepticism of aggressive carbon/GHG targeting. The root cause for both is increased industrialization due to improved technology. That technology has led to (among other things) improved farming and transportation methods that allow us to support 7 billion people where a couple centuries ago we had problems supporting 1 billion. (It took 90% of the population farming to feed ourselves in 1790, in 2010 it takes less than 3%.
) However, greenhouse gasses are some of the byproducts of that production technology, so as technology advances, we can support more people in better conditions than ever before, but we also produce more GHGs (and other pollutants.) Note, however, that as technology progresses, the amount of pollutants decreases per unit of stuff produced (carbon intensity
is one measure of that,) since waste products often represent inefficiencies in the manufacturing process.
Now to the skepticism: Current technological trends will not push carbon intensity down fast enough to meet emissions goals like those of the Kyoto protocol. Therefore, you need to produce less if you want to lower GHG output. But lowering output reduces our ability to support the population and improve living conditions. Remember, the poorest will always be the hardest hit. So, if lowering GHG output drives the US average standard of living down to that of, say, Slovakia, American poor might end up on the level of Sub Saharan Africa, and how will the poor in Asia and Africa who depend largely on the West for income growth fare?
It's pretty straightforward: To lower GHG emissions, you have to lower output. If you lower output, you'll negatively impact a lot of people. The policy difference between anti- and pro- climate change people is based on which they think will have a greater impact.