Katherine Hayhoe

410 PPM & Rising — CO2 Levels Reach Dangerous Levels

High atop Mauna Loa on the island of Hawai’i, there is an observatory scientists use to study the cosmos. At 14,000 feet above sea level, it has a clearer view of the heavens than most places on Earth. (It is a neighbor of Kilauea, the volcano that erupted this week after a 6.9 magnitude earthquake struck the island.) The observatory is also an ideal place to monitor the Earth’s atmosphere in a place with no local pollution from large cities. One of the instruments installed there measures the concentration of carbon dioxide in the air.