Further evidence on human global warming
"One of the standard skeptic 'arguments' is that all the observed changes are caused by natural variability, and often supposed to be due to solar activity," says Professor Wigley.Flashback: Priceless ClimateGate email 682: Tom Wigley tells Michael Mann that his son did a tree ring science fair project (using trees behind NCAR) that invalidated the centerpiece of Mann's work
"What we have shown beyond a shadow of doubt is that the climate changes we are observing cannot be due to the Sun or any other natural factors.
"Other published work has already shown a convincing and growing pile of pebbles of evidence for the dominant role of humans in climate change. Our paper adds a huge boulder to that pile."