
The graph above is known as “HadCET,” or the Central England temperature record, from 1659 to present, monthly in the beginning, daily from the late 1700s forward. When I last put up graphs using Greenland ice cores (link), it was pointed out to me that those ice cores are mere “proxies,” that is, we cannot know the actual temperatures of previous times and thus have to search for other indicators. I think that the implication was that the ice cores, which measure a shift of oxygen isotopes, for that reason are trash.
(Note on HadCET the rise of temperature from 1900-1950, before we began putting large quantities of CO2 in the atmosphere. What caused that? The warmest decade in the lower 48 during the 20th century was the 1930s, easily. What caused that? (No one knows.))*
Continue reading “Proxies and reality” →