Carbon dioxide levels hitting historic high is the final wake-up

At 415 ppm, carbon dioxide level is at highest ever in human history

A Graphical History of Atmospheric CO2 Levels Over Time

Permian–Triassic extinction event - Wikipedia

Carbon-dioxide levels haven't been this high in at least 800,000

Ancient Deepsea Shells Reveal 66 Million Years Of Carbon Dioxide

MeCCO Monthly Summaries :: Media and Climate Change Observatory

Preventing Carbon Monoxide Poisoning When Disasters Hit

Carbon dioxide hits 400 ppm for the first time in human history

CO2 has been higher in the past

Analysis: Growth of Chinese fossil CO2 emissions drives new global

CO2 hit record high in 2011 – UN report

Ocean acidification: A wake-up call in our waters

Carbon dioxide emission

Carbon dioxide at highest level in 650,000 years

Just how 'Sapiens' in the world of high CO2 concentrations?