Their latest study, released early on Monday (GMT), concludes that the average temperature of the Earth's land has risen by 1.5C (2.7F) over the past 250 years.
The team argues that the good correspondence between the new temperature record and historical data on CO2 emissions suggests human activity is "the most straightforward explanation" for the warming.
The paper reiterates the finding that the land surface temperature has risen 0.9C just in the last 50 years.
"Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of the rate of warming were correct. I'm now going a step further: Humans are almost entirely the cause." It's obvious that you cannot have an open mind to the data and not reach the conclusion that humans are contributing to global warming. Unfortunately, the GOP still doesn't agree with this reality. Why politics should decide science, I have no idea, but every year that the GOP keeps up this charade, we move further along to a much warmer climate. Personally, I don't think our governing structures are up to the challenge. I am sure that we will take steps to mitigate climate change, but I don't think there's much chance that our grandchildren are going to have the climate that we grew up with. As an aside: I don't like the 'sceptic' spelling of skeptic. I always read it as 'septic'. :/Prof Muller, from the University of California, Berkeley, said: "Three years ago I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming.
But I'm not sure I agree that steps to mitigate climate change are being taken. Or if they are enough. There are still too many and strong economic interests not to do so, even though is just a really bad idea to burn up all the oil right now. What's interesting here is that this project was funded by the very people that do not want to take steps to mitigate climate change, but the scientist responsible for it, being a scientist, had his mind reversed by the facts. Kudos to him.