Volcanoes play a dual role in influencing the climate. On the one hand, they release sulfur dioxide (SO2) into the atmosphere, which contributes to the formation of sulfate aerosols. These aerosols dissipate radiation and cool the atmosphere and the Earth’s surface in the short term. On the other hand, greenhouse gases such as carbon dioxide (CO2) and methane (CH4) emitted by volcanoes increase the heat effect and acidify the ocean. This creates uncertainty in climate projections for decades to come.
Previous studies have not accounted for small-amplitude eruptions because they have been difficult to capture from satellites. But a new study published in the journal Geophysical Research Letters shows that weak bursts of volcanic activity can neutralize up to 18.2 percent of the warming effects of anthropogenic greenhouse gas emissions in the 21st century. This means that volcanoes play a significant role in balancing the climate and can mitigate warming of the Earth.
Researchers at the University of Cambridge have developed a new model that has allowed them to make more accurate predictions of the effects of volcanic eruptions on the climate. The UKESM-VPLUME model combines the existing British UKESM Earth model and a one-dimensional Plumeria eruptive plume model. They used paleodata on SO2 concentrations from polar ice cores over the past 11,500 years and satellite data on SO2 emissions from 1979 to 2021. This allowed them to account for atmospheric conditions and more accurately predict volcanic plume dynamics and sulfur dioxide emission heights.
The simulation results showed that volcanic emissions have a stronger cooling effect on the climate than previously assumed. This is due to the fact that previous studies did not take into account weak bursts of volcanic activity. Now it is clear that these weak eruptions can also significantly affect the climate.
The new study underscores the importance of considering volcanic emissions when making climate projections. Their unpredictable nature and multidirectional effects on the climate make them a significant factor to consider when analyzing climate change.
It should be noted that volcanoes are not the main sources of anthropogenic heating of the atmosphere. They only offset some of this heating. The main sources of anthropogenic greenhouse gas emissions remain industry, transport, and other human activities.