Here it is. You were expecting it. You've learned from repeated experience that every "-Gate" has a smoking gun. ClimateGate is no different.
Willis Eschenbach is the chap who found the smoking gun. Willis is a frequent commenter and contributor at Climate Audit and What's Up With That. Willis found the smoking gun in Darwin, Australia.
Willis looked at Darwin and found that the only continuous record over the last century, at Darwin Airport, shows a mild decline in temperature, about 0.5 deg C. All of the decline happens in the first half of the 20th century; the second half shows a mild warming. Guess what the climate scientists delivered as an adjusted record? A strong warming trend of +1.2 deg C.
Way to go fellahs!
Of course, it's impossible to figure out what the Climatic Research Unit did with the data. CRU doesn't divulge raw data and methods. Only the unimpeachable results.
But NOAA's Global Historical Climate Network (GHCN) does divulge the raw data. And Willis finds that they have just punched in huge increases in temperature, based on trends from nearby records, to fill in missing info.
Only nearby for Darwin is 500 km away!
My guess is that this isn't a conspiracy. It's just laziness. The Climate scientists ginned up a method of homogenizing data that worked for the US and Europe, and then applied it to the rest of the world without thinking and checking too carefully. Or maybe they made cursory checks way at the end of the project when they had run out of money. Probably they just threw up their hands and just walked away from the problem.
But the fact is that the whole job needs to be done over. Then we'll find out just how serious the current warming is. If there is any.
And all that must come before we can determine whether humans are responsible for the warming. If any.
Go on. You'd better read the whole thing.