Temperatures are on the rise (March was the fifth warmest ever recorded) and so is the level of carbon dioxide in Earth’s atmosphere. The concentration of carbon dioxide levels reached an all-time high in April, with a monthly average concentration of 410.31 parts per million, according to data from the Mauna Loa Observatory in Hawaii.
The observatory has been used by the Scripps Institute of Oceanography since 1956 to continuously collect data on the atmosphere, and by the National Oceanic and Atmospheric Administration since 1974. Data gathered from the observatory shows a sharp increase in the levels of carbon dioxide, which have increased more than 90 parts per million since then.
Data gathered from ice cores containing ancient air bubbles reveal CO2 levels from the last 800,000 years. Those ice cores show that while carbon dioxide levels have always fluctuated, they were never higher than 300 parts per million before the Industrial Revolution, according to Scripps.