Image source: https://gogreenr12.org/wp-content/uploads/2017/08/2017083105.jpg
There is much debate about the role of humans in global climate change (Global Warming). Some experts argue that the role could be through fossil fuel and the release of chlorofluorocarbons (CFCs) of gas, and they argue that human interaction poses more threats to the Earth's atmosphere than natural processes, such as volcanic eruptions.
This makes the understanding of the role of volcanic eruptions in influencing global climate change is very important. Whatever the source, changes in particle composition in the Earth's atmosphere produce three effects:
Impact on Ozone Hydrochloric (HCl) has been shown to be effective in destroying ozone however, recent studies have shown that HCl from volcanic activity (Volcanic Hcl) only goes to the troposphere (below the stratosphere), this is caused by the rain that washes it first.
Thus, it can be said that Hcl never had a chance to react with ozone. On the other hand, satellite data after 1991, Mt.Pinatubo (Philippines) and Mt.Hudson (Chile) eruptions showed a 15-20% ozone loss, and 50% the missing ozone is above Antarctica. Thus, it appears that volcanic eruptions can play an important role in reducing ozone levels.
However, the role is not directly because it can not be directly attributed to Volcanic HCl. The resulting eruption particle, or aerosol, appears and interacts with chlorine and bromine – a compound of manusiachlorofluorocarbon (CFC). Fortunately, volcanic particles will exit from the stratosphere in two or three years, so the effect of volcanic eruptions on ozone depletion is only in the short term.
Although volcanic aerosols provide catalysts for ozone depletion, actual criminals in destroying ozone are human-produced CFCs. Scientists expect the ozone layer to recover due to restrictions on CFCs and other ozone-depleting chemicals by the UN in the Montreal Protocol on Substances That Ruil the Ozone Layer. volcanic eruptions in the future will cause fluctuations in the recovery process.
Impact on Increasing Green House Gas (GHG)
Volcanic eruptions can increase global warming by adding CO2 to the atmosphere. However, the amount of CO2 produced by human activity each year is still greater than the volcanic eruption. TM Gerlach (1991, American Geophysical Union) notes that CO2 from human activity is 150 times more than CO2 volcanic eruptions.
The small impact of global warming caused by greenhouse gases is due to the lingering impact of global cooling caused by eruption particles generated in the stratosphere (fog effect). Heating of greenhouses on earth is very clear since 1980. Without the effects of cooling eruptions such as El Chichon (1982) and Mt. Pinatubo (1991), greenhouse heating will become more obvious.
Effect of Haze (Haze Effect)
Volcanic eruptions have a greater fog effect than on the greenhouse effect, and thus they can lower average global temperatures. According to Gerlach, over the years the contribution of the largest volcanic activity of the fog effect is when ash particles are suspended in the upper atmosphere and blocking solar radiation. The 1980s from Mt.St Helens lowered global temperatures by 0.1 degrees Celsius, the eruption of El Chichon lowered global temperatures by three to five times. Although the Mt. St Helens eruption extracted large amounts of ash in the stratosphere, the El Chichon eruption released materials volcanic in much greater quantities than sulfur-rich gases (40x more).It can be concluded that volcanic material volumes that emit during the explosion are not the best criterion for measuring their impact on the atmosphere. The amount of sulfur rich gases seems to be more important. Sulfur mixes with water vapor in the stratosphere to form dense clouds with small sulfuric acid droplets.This test takes some time years to complete their chemical reactions and they are able to reduce tropospheric temperatures because they absorb solar radiation and spread it back into space.
Examples of Global Cooling Impacts Due to Historic Mountain Volcanic Eruptions: The observational evidence shows a clear correlation between historic eruptions and cold climate conditions in the following years. Three notable historical examples are described below:
Laki (1783) eastern US recorded the lowest temperature ever winter on average 1783-1784, about 4.8 degrees Celsius.Europe also experienced a very severe winter.Benjamin Franklin argued that the cold conditions caused by disruption of sunlight by dust and gas was made by the eruption of Mount Iceland (Gunung Laki) in 1783. Laki's eruption was the greatest eruption of the historical period. The Franklin hypothesis is the same as modern scientific theory, which shows that the large SO2 volume is the main cause in fog – the effects of global cooling.
Tambora (1815) Thirty years later, in 1815, the eruption of Mount Tambora, Indonesia, resulted in a very cold spring and summer of 1816, which came to be known as the year without summer. Tambora eruptions are believed to be the greatest of the last ten thousand years. and Europe feel the impact is quite severe. Snow and snowfall occurs in June, July, and August. The destruction of maize forced the peasants to slaughter their animals. The fountain was opened to feed the hungry. The sea ice expanded to the shipping area of ??the Atlantic Ocean, and Alpine Mountain glaciers grew to the mountainside.
Krakatau (1883) The eruption of the Krakatau volcano in Indonesia in August 1883, twenty times as powerful as the 1980 eruption of Mt.St Helens. The Krakatau eruption is the second largest eruption in history, dwarfed only by the eruption of Tambora which is a neighbor and erupted in 1815 (see above).
For months after the eruption of Krakatau, the world experienced winter weather, sunsets with shimmer, and dusk prolonged due to the spread of aerosols throughout the stratosphere. An unusual and prolonged sunset creates a considerable contemporary debate about the origin of this phenomenon. This phenomenon also provides inspiration for the artists depicted at sunset. Some 19th-century paintings, two of which are recorded here.
In London, the Krakatau sunsets were clearly distinct from the familiar red sunsets through the smoke-laden atmosphere of the city. This is demonstrated in the painting shown here of a sunset from the banks of the Thames River, created by artist William Ascroft on November 26, 1883.
May be useful.
Sources: https://www.geology.sdsu.edu (Translated and adjusted by Daniel Jones B)