Discuss If Volcanic Activity Affects Climate Chang Essay

Discuss if volcanic activity affects climate change.

Volcanic activity generally lowers the global temperature due to its emissions during eruptions, thereby influencing climate change (Wikipedia: “Climate Change”, n.p.). However, its impact on climate change is small as compared to other causes, mainly human activities.

A climate change is an extended period of alteration to weather events, indicated by a global variation in average surface temperature and precipitation (Wikipedia: “Climate Change”, n.p., Adler et al., n.p.). Volcanic activity largely refers to eruptions, whereby magma, ash, dust and other gases are expelled from the vent of a volcano and introduced into its surroundings and atmosphere (kath18, n.p.). Gases released comprise mostly of water vapour (H2O), carbon dioxide (CO2) and sulphur dioxide (SO2), all of which contribute to the greenhouse effect – a process whereby greenhouse gases absorb the radiative energy leaving a planetary surface (Wikipedia: “Greenhouse effect”, n.p., USGS 2010, n.p.). Therefore, in determining whether volcanic activity brings about climatic changes we should assess how eruptions affect global temperature and precipitation.

Emissions of sulphur dioxide cause global cooling. Figure 1 illustrates how the reaction of sulphur dioxide and water produces sulphuric acid (H2SO4). Upon condensation, this acid then turns into fine sulphate aerosols, thus forming a dense optically bright haze layer that reflects the sun’s radiation back into space, thereby lowering tropospheric and stratospheric temperature (USGS 2008, n.p., Pidwirny, n.p.).

With this decrease in temperature, global changes in precipitation can also be observed.   Lowered temperatures inhibit evaporation of water from Earth’s surface and certain areas may experience lower rainfall than usual (Dybas, n.p.). On the other hand, there can be unexpected increases in rainfall over other regions. A possible explanation for this could be the impact of strong El...