Ferdinand Engelbeen, Renee Hannon, and David Burton December 2024 Since the beginning of the Industrial Revolution in the late 1700s, the average concentration of Earth’s atmospheric carbon dioxide (CO2) has increased by about 140 parts per million by volume (ppmv) to the current amount of about 420 ppmv. This is much higher than concentrations of the past 800,000 years, which … Continue reading Human Contribution to Atmospheric CO2: How Human Emissions Are Restoring Vital Atmospheric CO2