"...there is the contention by wolfgang knorr of the department of earth sciences at the university of bristol in england that carbon dioxide levels in the atmosphere are about where they were 160 years ago." (as quoted by ken ward jr.)
"...there is the contention by wolfgang knorr of the department of earth sciences at the university of bristol in england that carbon dioxide levels in the atmosphere are about where they were 160 years ago." (as quoted by ken ward jr.)
eocene:210
"paleobotanical evidence for near present-day levels of atmospheric co2 during part of the tertiary".