The University of East Anglia and the Met Office's Hadley Centre have released their global temperature estimates for the present year, in preliminary form.
IT turns out that this is the seventh warmest year since 1850. Furthermore, the eleven warmest years since 1850 have all occurred during the last 13 years.
In other words, it is now .. this year, this decade, this month, etc. ... the warmest it has been since we've started keeping direct temperature records.
Even conditions that tend to cool the atmosphere, such as the La Nina event we are currently experiencing, have not caused a weakening in this trend.
You can get all the info referred to here.
Environment
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Interesting. Many people say that "the world has been warmer before", and point to the Milankovitch cycle graphs from ice cores in the distant past ( > 3,000 years ago), but forget completely that the rate at which the planet is apparently warming is the highest it's ever been in natural phenomena.
For an image like this: (full resolution)
http://upload.wikimedia.org/wikipedia/commons/7/77/Vostok_420ky_4curves_insolation.jpg
The current rate of warming (0.178 degree K/decade) translates to a perfectly vertical for 5.75 degrees (a pixel represents about 325 years, and the major temperature shift at ~325 kya represents an 11-degree change over approximately 11,000 years. (~.01 degree Kelvin per decade)
Our current rate of warming is some 17 times faster than recognized natural rates from ice cores. I'd say that's statistically significant.
Posted by: AtheistAcolyte | December 14, 2007 1:24 PM
AA:
Note that the Vostok core data you link to shows the maximum CO2 in parts per million (volume) at less than about 295-300 for all of the time represented. The current level is cloeser to 380 or higher. We have not seen CO2 concentrations as low as those shown in this core data in somewhere between 50 and 100 years in the past (you could check this, but I'm pretty sure that is close).
It is not the case that temperature correlates perfectly with CO2, so I can't say that the world has not really been warmer (since the beginning of the Cenozoic) but it may be accurate to say that the amount of free carbon floating around has not bee higher for a very long time.
Posted by: Greg Laden | December 14, 2007 2:12 PM