Well I'm a global warming sceptic, I see it as nothing more than our governments finding yet another method of increasing taxation or creating an artificial carbon trading market for their mates in the stock markets.
Historically the world has had dramatic changes in climate, both hot and cold. 90% of our climate is influenced by the position of the magnetic poles. The link between the position of the North/South Poles and weather can be seen by looking up historical global magnetic maps and known plant species that grow in certain weather types, or written records from the various civilisations going back to about 3000BC (in the case of India).
In recent historical times (Europe's Middle/Dark Ages) you end up with the North Pole under Siberia. Europe had long winters starting in late October and running into March or April, food was scarce because of the short growing season, famines and plague were common. In contrast the civilisations of SE Asia and China were flourishing with mild climates and long growing seasons. There are other exaples during the heyday of the Roman Empire, the Persian Empire, Indian sub continent, Japanese, etc. Mild weather allows for growing an excess of food, as soon as you have more food than you can eat, you can build, create art, write books, philosophise, explore, this is when civilisation takes a big leap forward.
Currently the North Pole is under Canada and is heading towards true North, until the 1990s it was moving at about 10kms/year, since late 90s its sped up to 40kms/year. When it was moving South, Europe had those mild Summers of the 1930s and 40s.
Does Global Warming exist? No! Its just a natural event.
Global excuse for Taxation? Yes! Its an unnatural event created by politicians.