How convenient: The anthropogenic climate signal allegedly showed up immediately after the coldest year in the Arctic temperature record.

The Joy Of Satellites | Real Science

NSIDC claims that the modern satellite record began in 1979. This is a pretty marginal claim, given that we have accurate satellite data going back a decade earlier.

But 1979 is a very convenient year for them – because it was the coldest year in the Arctic temperature record.

...By starting in 1979, they are able to produce all kinds of seemingly suitable funding graphs.

How convenient: Interview with Christopher Castro

....entirely consistent with the conclusion of the IPCC Fourth Assessment Report that the anthropogenic signal in climate becomes statistically discernible after about 1980 or so.