According to NASA, 2012 was the 9th warmest year since 1880. Now the bad news: all of the 8 warmer years have come since the year 2000, with 2005 and 2010 the warmest years on record. A one year spike can be caused by short-lived factors, but this is not a one year or even three or five year increase.
Gavin Schmidt of NASA's Goddard Institute for Space Studies (GISS) explains:
"One more year of numbers isn't in itself significant. What matters is this decade is warmer than the last decade, and that decade was warmer than the decade before. The planet is warming. The reason it's warming is because we are pumping increasing amounts of carbon dioxide into the atmosphere."
Carbon dioxide traps heat, and its existence in the atmosphere correlates well with a steady rise in global temperatures over the last decade. Carbon dioxide occurs naturally, such as when you exhale, and is also chuffed out into the atmosphere by humans burning fossil fuels for energy. It is measured in the atmosphere in "parts per million." This number was 285 in 1880, 315 in 1960 and 390 today. The average global temperature has risen 1.4 degrees Fahrenheit (0.8 Celsius) in this time.
That climate change is real is indisputable and that humans are contributing is disputed, but very little by climate scientists. Climate scientists with no ties to the energy industry overwhelmingly agree that humans contribute to climate change in a significant way. Regardless, given that the Earth is warming, droughts are increasing and water is tipping toward scarcity, isn't now the time to find ways to save water, plant trees and invest in renewable energy?