Disaster was narrowly averted Under 180 ppm atmospheric CO2 concentration, life on earth begins to die. The earth came very close to that point not long ago during the Ice Ages (20,000 years ago). Then the planet warmed naturally, and an increase in atmospheric CO2 to over 200 ppm followed (new study here). The earth … Continue reading In Geological Terms, Today’s Atmospheric CO2 Concentrations Are Still Uncomfortably Low