A new study led by UWAB alum Sanjoy Som together with UWAB professors Roger Buick and David Catling and others implies that early Earth’s atmospheric pressure 2.7 billion years ago was less than half of modern day. The researchers used gas bubbles trapped in ancient sea-level lava flows as a “paleobarometer”. The sizes of the bubbles record the pressure of the atmosphere bearing down on the cooling lava billions of years ago. This low atmospheric pressure suggests that early microbes may have been consuming atmospheric nitrogen, but there was not an efficient process to release that consumed nitrogen back to the atmosphere like there is today. Read the UW News summary!