The Berkeley Earth Project is a very ambitious attempt to accurately assess the state of “Global Warming” in a very systematic and scientific way, free from the many biases, politics, and advocacy challenges that have arguably plagued the process to date. Preliminary findings are just out here a bit prematurely, as the director of the project Muller recently testified to the US Congress: http://berkeleyearth.org/Resources/Muller_Testimony_31_March_2011
Note that the results here are based on 2% sample they are using to validate their methods before they apply that method to the entire set of some 1.6 billion temperature records, a project that they maintain (and I agree) will result in the best measure to date of global temperature change.
Not surprisingly the 2% looks a lot like the temperature record we see from the major measurers of such things – CRU in England and NASA in the USA. My gut expectation about the final record is that it will reflect a slight decrease in observed warming along with a significant, though modest, increase in the “uncertainty” of such measurements. Why? That finding would be very consistent with the fact that most of the climate scientists are doing excellent work that is good and only very slightly compromised by the alarmist bent. That bent can’t change the data but I think it has inclined those – particularly in Paleodendrochronology – to view questionable assumptions by other scientists too sympathetically. Sort of a “circling of the wagons” has happened as tree ring science emerged from almost total obscurity to the single most important “climate signal” in the global warming controversies. The politics and alarmism and advocacy have very unfortunately led to some questionable interpretations and assumptions despite the obvious which are nearly rock solid findings of a global temperature rise over the last century.
Berkeley Earth is a great approach and I’m anxious to see how their transparent and hopefully unimpeachable methodology will shed light on global warming / climate change issues.
P.S. IMHO 1.there is slight global warming, 2. it’s mostly human caused, 3. it’s not going to hurt much and 4. (most importantly) YOU (and I, and even the most fervent alarmist) are almost completely unwilling to do the things needed to change our warming prospects enough that it would make more than a trivial difference in the scheme of things. If you travel much via planes or cars, keep your house between 65 and 85 degrees, fail to retrofit much of your life to save energy, etc, etc, etc then you are THE PROBLEM and you are NOT PART OF THE “SOLUTION”. Sorry, but you won’t change and many of you won’t even build nuclear power plants – part of the no-brainer solution to energy needs.