WHEN HUMANS FIRST EVOLVED the carbon dioxide level in the atmosphere was just right to keep most of the Earth comfortable for humans.
THEN IN THE MID-19TH CENTURY the Industrial Revolution needed large quantities of energy, mostly in the form of heat, to power the newly invented machinery. And when wood, oil, or coal were burned additional carbon dioxide was added to the atmosphere. And the Earth began to warm. Now the concentration of carbon dioxide in the atmosphere is the highest it has been in 600,000 years.
A SIMPLE "TREND LINE" expansion of NASA data from 1860 to 2017 suggests that temperature rise is exponential, at least in the near term.