Scientists from the Laboratory for Research on the Ozone Layer and Upper Atmosphere at St. Petersburg University conducted a computer modeling study illustrating the impact of volcanic activity on climate, weather, and the ozone layer in the 21st century.
The journal Atmosphere notes that, according to scientists, volcanic eruptions could lead to warmer winters in the Arctic and northern Europe.
“We conducted a series of 25 independent simulations for the period between 2020 and 2100, according to a scenario that assumes high greenhouse gas emissions,” said Yevgeny Rezanov, director of the laboratory. “Each simulation included the eruption of five volcanoes of varying intensity at random, including three strong volcanoes, one moderately intense volcano, and one weak one. This approach allowed us to estimate the range of potential impacts and compare them with a simulation that did not include any volcanic activity.”
The analysis showed that expected volcanic eruptions over the next few decades will not have a major impact on the pace of global climate change, as global temperatures are expected to continue rising by the end of the century regardless of volcanic activity.
Researchers indicated that the most significant impact will be seen in Northern Europe, where winter temperatures could rise by about one degree Celsius, representing roughly one-third of the total projected regional warming. This is attributed to the warming of the stratosphere over the tropics, which accelerates the movement of warm air masses from the Atlantic Ocean into Eurasia. Average annual rainfall in Northern Europe is also expected to decrease by about 36 millimeters.
The researchers added that average temperatures in the Arctic are also projected to rise. Paradoxically, volcanic activity may contribute to an expansion of sea ice, which reflects sunlight more efficiently, thus amplifying the cooling effect. According to the calculations, 16 percent of the Earth's landmass, particularly in the Arctic and Eurasia, has a greater than 50 percent probability of daily maximum temperatures increasing by 0.5 degrees Celsius. In contrast, the model results showed no significant climate changes in North America.
The study also indicates that volcanic activity has a dual effect on the ozone layer. While it leads to chemical ozone depletion in tropical regions, strong air currents contribute to the transfer of ozone towards the Arctic. As the concentration of ozone-depleting compounds continues to decline thanks to adherence to the Montreal Protocol, the chemical effect is expected to gradually diminish. Scientists believe that by the end of the 21st century, volcanic activity will cause the ozone layer to shift from the equator towards the poles, which will also affect atmospheric temperatures.
The scientists concluded the study by stating that volcanic activity will not be able to stop global warming, but it will significantly affect climatic conditions in specific regions of the world by changing rainfall patterns and temperatures, as well as influencing the frequency of natural disasters.
