Nine of the top ten warmest years in the modern meteorological record have occurred since the year 2000. Last year was another one of them, coming in at 9th warmest since 1880.
The map above shows temperature anomalies, or changes, by region in 2011; it does not depict absolute temperature. Essentially, the map shows how much warmer or cooler each region was in 2011 compared with an averaged "base period" from 1951-1980. The line plot shows yearly temperature variations (from the base period average) for every year from 1880 to now. (For more explanation of how the analysis works, read World of Change: Global Temperatures.)
On January 19, 2012, researchers at NASA's Goddard Institute for Space Studies (GISS) released their annual analysis of global temperatures, noting that Earth's land and ocean surfaces continue to experience higher temperatures than several decades ago. The global average temperature for 2011 was 0.92 degrees Fahrenheit (0.51 Celsius) higher than the mid-20th century baseline.
"We know the planet is absorbing more energy than it is emitting," said GISS director James Hansen. "So we are continuing to see a trend toward higher temperatures. Even with the cooling effects of a strong La NiƱa influence and low solar activity for the past several years, 2011 was one of the ten warmest years on record."