josephv,
But he does not relate that centuries up trend with those over the previous centuries.
Over the last 2000 years there have been other temperature uptrends of similar scope and also downtrends of similar scope.
Why is the 19th century uptrend man made and all of the others are not?
And if 1998 is the current peak, why are we necessarily still in an uptrend, albiet with a kink in it? Why was there a downtrend from 1900 to 1910 and from 1940 to 1950 and 1960 to 1980? In fact, during the depression when manufacturing was weak, there is a definite up trend of similar magnitude to the current one, but between 1940 to 1950, where there were enoumous amounts of manufacturing for the war years and then reconstruction, there is a down trend?
Why does he not look at the millenia long trend, or longer, and see that current decade and century long trends are not abnormal and current temperatures are not abnormally high. And man cannot be blamed for most of those.