The mystery deepens: Where did that decline go?
'If 1958 temps were similar to 1990's, it rewrites the entire claim of unprecedented warming'. The most mysterious period is from 1958 to 1978, when a steep 0.3C decline was initially recorded in the Northern Hemisphere. Years later, this was reduced so far it became a mild warming against the detailed corroborating roabcore evidence. Raobcore measurements are balloon readings. How accurate are they? They started in 1958, twenty years before satellite temperature records (which are renowned for their accuracy). Put the two methods side-by-side, and they tie together neatly, telling us that both of them are accurate, reliable tools. WUWT: More on the National Geographic Decline.