Want to use a C3 chart? Policy here.
"Unprecedented" global warming during late 20th and early 21st centuries? Actually, the real unprecedented warming (and extreme climate change) happened well before the industrial age, as the below charts reveal (in paleo-age descending order). Review the charts below and decide for yourself. (BTW, here is a collection of modern global temp and regional temp charts.)
OTHER CHARTS & INFORMATION OF INTEREST