"Warming of the climate system now is unequivocal," the American Meteorological Society (AMS) concluded in a 2012 official statement. Measurements show that Earth's surface temperature rose by 1.4 degrees Fahrenheit (0.8 degrees Celsius) between 1901 and 2010, with most of that change (0.9 degrees F or 0.5 degrees C) occurring over the last 20 years of that period, and all 10 of the warmest years happening since 1997 [source: AMS]. While the planet has warmed and cooled before, that's the most rapid increase in the past 1,300 years [source: NASA].
So, why do so many people disbelieve global warming? There are a lot of dissenting voices out there. According to one study, an assortment of organizations, often tied to the oil industry, spent nearly $560 million between 2003 and 2010 to fund groups that deny climate change, many with links to sympathetic media and politicians [source: Drexel University]. As a result, if you listen to talk radio or peruse the comments on news Web sites, you'll find the following 10 statements that supposedly disprove global warming repeated. The problem is that they don't disprove anything. Here's why.