Well, it's a tie actually. The final tallies are in and 2010 is even with 2005 as the warmest year on record. NASA and NOAA independently released their own reports yesterday, confirming the improbable and remarkable statistical tie. NASA's Goddard Institute for Space Studies explains:
The two years differed by less than 0.018 degrees Fahrenheit. The difference is smaller than the uncertainty in comparing the temperatures of recent years, putting them into a statistical tie.
Surface temperature records go back to 1880, and while both NASA and NOAA's National Climatic Data Center use the average global surface temperature as their variable, they use different methodologies (as Climate Central explained nicely here). Two methodologies producing the same result only further cements the point.
Also, keep in mind that these records are being set during "the deepest solar minimum in nearly a century," which totally refutes one common argument of the climate skeptic. What's more, the second half of 2010 was unique for its strong La Niña conditions, "which bring cool sea surface temperatures to the eastern tropical Pacific Ocean," as James Hansen, director of GISS noted:
"Global temperature is rising as fast in the past decade as in the prior two decades, despite year-to-year fluctuations associated with the El Niño-La Niña cycle of tropical ocean temperature."
The NCDC handily provides a nice chart of the warmest ten years on record, all of which have been lived through by anyone older than 14:
Hansen, the director of GISS, didn't mince words in talking about 2010's chances of staying atop the charts:
If the warming trend continues, as is expected, if greenhouse gases continue to increase, the 2010 record will not stand for long.
Heck, here's another look at the warming, from NASA:
I know it's might feel like overkill to write all the time about how, yes, it actually is getting warmer. Seems obvious enough, right? But every day, people are being duped into thinking that the clear and unfortunate (I won't say inconvenient) truths of climate change aren't actually true. So I feel it's important to drive the point home with the relevant facts whenever they are as clear and telling as they are today.
UPDATE: In response to a reader's comment, the headline of this post has been updated to clarify that 2010 is the hottest year since record keeping began.