NASA has released data on Earth's global average surface temperature for 2011
showing that last year was the ninth-warmest since records began, in the late 1800s. Ninth warmest may not sound like a big deal, especially in a media environment fixated on first, biggest, best, but it still means that nine of the ten warmest years on record have occurred since 2000—and the other warmest year was in 1998.
In 2011, the average temperature for the year was 0.51°C above the mid-20th century baseline average. Compared to the warmest years on record (2010 and 2005, pretty much tied), last year was 0.12°C cooler than that.
NASA Goddard Institute for Space Studies director Dr James Hansen commented on the data:
We know the planet is absorbing more energy that it is emitting. So we are continuing to see a trend towards higher temperatures. Even with the cooling effects of a strong La Niña influence and low solar activity for the past several years, 2011 was one of the 10 warmest years on record.