It has snowed in Alberta, Canada on August 1st in the dead of summer. Such strange events like this have not been common. Europe is burning from heat when buildings do not even have air conditioning because they never needed it. The concern that we are headed into a volcanic weather event really needs our attention. Volcanos emit C02, but they are a major source of something far worse – SO2. We have all heard of the London Fog. However, in 1952, some 4,000 people in Britain died from breathing in the fog.
Volcanos emit a lot of Sulfur dioxide (SO2) which smells like rotten eggs. Humans also contribute by burning coal and other fossil fuels which are the largest source of sulfur dioxide from human activities. However, volcanoes and forest fires are THE major natural contributors. What is important to understand is that sulfur dioxide is a pollutant that does impact the climate. Once SO2 is in the atmosphere, it can easily form sulfate ions. These are negatively charged particles made of up of sulfur and oxygen atoms. Since they are negatively charged, sulfate ions combine with water vapor in the atmosphere and then form small droplets of sulfuric acid (H2SO4). You may hear of this as acid rain. CO2 does not act in this manner.
When a volcano erupts. we then see huge amounts of sulfur dioxide are released into the stratosphere which will then convert to sulfates. There is a qualification needed here because sulfates formed at lower altitudes are removed from the atmosphere in just a few weeks through settling and precipitation. However, the SO2 emission from volcanos reach the upper bounds of the atmosphere and create aerosols that are mainly tiny droplets of sulfuric acid that then stay in the atmosphere for about two years. These SO2 droplets reflect incoming solar radiation back into space yet absorb both incoming solar radiation and outgoing infrared radiation. The net result, is simply that SO2 reduces the amount of energy reaching the lower atmosphere and Earth’s surface. Hence, we get global cooling of the lower atmosphere and Earth’s surface.
Consequently, it is the volcanic eruptions are of considerable impact on global climate and are a proven fact rather than theory as is the case with CO2.