Trace Gas Sensors Demonstrate Diffusion

Ecologist Joshua Fisher holds a trace gas sensor in the Rincon de la Vieja National Park, Costa Rica. In the background is another sensor placed at the mouth of a fumarole: a crack in the Earth's surface that passively emits gases from the volcanic system beneath. The two sensors demonstrate how quickly carbon dioxide diffuses from its source into the atmosphere, dropping from a reading of 5,198 parts per million (ppm) at the fumarole to 569 ppm within a few feet. Fisher and his team placed sensors at locations across the forest to measure emissions, in an effort to understand how vegetation responds to elevated levels of carbon dioxide.