From the bubbling magma of volcanoes to the stench of hydrogen sulfide, the research on Earth’s atmosphere and climate is ongoing. Now, a new study led by the University of Washington shows that even in their quiet phases, volcanoes may be releasing more climate-changing gases than previously thought. In this blog post, we’ll discuss why this research is so important and what it could mean for a better understanding of Earth’s atmosphere and climate.
The study, published in Geophysical Research Letters, analyzed layers of an ice core from central Greenland to calculate levels of sulfate aerosols between the years 1200 and 1850. The team deliberately avoided any major volcanic eruptions and focused on the pre-industrial period, when it’s easier to distinguish the volcanic and marine sources. What they found was that on longer timescales, the amount of sulfate aerosols released during passive degassing is much higher than during eruptions. In fact, passive degassing releases at least 10 times more sulfur into the atmosphere, on decadal timescales, than eruptions, and it could be as much as 30 times more.
This research has implications for better understanding Earth’s atmosphere and its relationship with climate and air quality. Knowing the natural, pristine atmosphere in terms of aerosols is a first step to better understanding how humans have influenced our atmosphere. In addition, the discovery that non-erupting volcanoes leak sulfur at up to 3 times the rate previously believed is important for efforts to model past, present and future climate. Aerosol particles, whether from volcanoes, vehicle tailpipes or factory chimneys, block some solar energy. If the natural levels of aerosols are higher, that means the rise and fall of human emissions have had less of an effect on temperature than previously believed.
This research also has implications for predicting climate change and understanding the full effects of rising heat-trapping greenhouse gases. To improve global climate models, the authors suggest that the best way to improve estimates of volcanic emissions is to really think about the hydrogen sulfide emissions.
Overall, this study shows that even in their quiet phases, volcanoes are leaking a surprisingly high amount of their atmosphere- and climate-changing gases. This research has implications for better understanding Earth’s atmosphere and its relationship with climate and air quality, and it could help us to better predict climate change.