Guest post by John A.
I’ve just had a guest post on Jeffid’s the Air Vent, showing that between 1988 and 2010 there is a strange mutability in the trend of global air temp as produced by GISS, under Jim Hansen’s by-line.
Folks here might be interested. According to GISS, in 1988 the early 20th century warmed at about the same rate as the late 20th century. By 1999, the late 20th century warmed 2.3 times faster, increasing to 2.8 times faster by 2010.
This increase in rate wasn’t due to an accelerating late 20th century trend. It’s mostly due to modifications of the 1880-1920 record.
Do the systematic changes show an increasingly sophisticated understanding of early 20th century natural variability? A better perception, perhaps, of UHI effects or station site inhomogeneities? None of that seems likely.
Rather, it seems more likely that anthropogenic climate change has much more to do with the climate data than it does with the climate itself.
Well worth a read.