Settled science: Human CO2 emissions made the temperature shoot up starting in the late 19th century, or maybe the late 20th century, or something

- Bishop Hill blog - Marcott et al

New Scientist covers the paper here. Interestingly they reckon the temperature rise began in the late 19th century.

Then, in the late 19th century, the graph shows temperatures shooting up, driven by humanity's greenhouse gas emissions.

This seems odd, because it is generally understood that carbon dioxide emissions were too small to affect the climate before the 1950s.

The Global Warming Desk Reference - Bruce Elliot Johansen - Google Books

[1989: Stephen Schneider wrote, "I strongly suspect that by the year 2000 increasing numbers of people will point to the 1980s as the time the global warming signal emerged from the natural background of climatic noise"]