NASA: Last decade was warmest ever

(CNN) -- The first decade of the 21st century was the warmest ever on Earth according to data released by scientists at NASA. The U.S. space agency's data also revealed that 2009 was the second warmest year since temperature records began in 1880, and only narrowly cooler than 2005, the warmest year ever. 2008 was the coolest year of the decade but this was attributed to a strong La Nina which causes extensive cooling of the central and eastern Pacific Ocean. James Hansen, director of NASA's Goddard Institute for Space Studies (GISS) said in a statement: "There's substantial year-to-year variability of global temperature caused by the tropical El Nino-La Nina cycle. When we average temperature over five or ten years to minimize that variability, we find global warming is continuing unabated." Read More