“Global warming” refers to the global-average temperature increase that has been observed over the last one hundred years or more. But to many politicians and the public, the term carries the implication that mankind is responsible for that warming. This website describes evidence from my group’s government-funded research that suggests global warming is mostly natural, and that the climate system is quite insensitive to humanity’s greenhouse gas emissions and aerosol pollution.
Believe it or not, very little research has ever been funded to search for natural mechanisms of warming…it has simply been assumed that global warming is manmade. This assumption is rather easy for scientists since we do not have enough accurate global data for a long enough period of time to see whether there are natural warming mechanisms at work.
The United Nation’s Intergovernmental Panel on Climate Change (IPCC) claims that the only way they can get their computerized climate models to produce the observed warming is with anthropogenic (human-caused) pollution. But they’re not going to find something if they don’t search for it. More than one scientist has asked me, “What else COULD it be?” Well, the answer to that takes a little digging… and as I show, one doesn’t have to dig very far.
But first let’s examine the basics of why so many scientists think global warming is manmade.
Link to full Article Global Warming « Roy Spencer, PhD.