Environmental Geology: Active Volcanoes - Essay Example

About 550 volcanoes have erupted on the Earth's surface since recorded history and out of these, an estimated 60 volcanoes are active each year (Montgomery, 2006). Recently, satellite technology makes it possible to monitor volcanic activity. These satellite technologies help to predict atmospheric impact by global-scale volcanism to potentially save lives and property during future eruptions. However, the environmental impacts of eruptions of active volcanoes can never be avoided.

In the Catalogue of Active Volcanoes of the World, the International Association of Volcanology defines an active volcano as one that has erupted during historic times (Montgomery, 2006).  Mount Merapi means “Fire Mountain” in Indonesia and is an active stratovolcano located on the border between central Java and Yogjakarta. On the other hand, Laki is a legendary Icelandic volcano, which has lain dormant since its huge eruption in 1783.

Satellite technology now makes it possible to monitor volcanic activity in even the most isolated corners of the globe, and to routinely observe changes in the Earth’s surface that may signal an impending eruption. This help identifies those volcanoes presenting the greatest danger. The MODIS Thermal Alert System, also known as MODVOLC, now enables scientists to detect volcanic activity anywhere in the world within hours of its occurrence (Jha, 2009). Using MODVOLC, volcanologists have seen many active volcanoes that previously went undetected.

Aside from serious disasters posed to humans and property, active volcanoes also produce serious environmental effects (Monroe, Wicander, & Hazlett, 2006). The commonly-known threat a volcano can present is the flow of super-heated rock known as lava. This lava causes fires and will destroy everything in its path. In addition, tsunamis can develop and damage shorelines. Furthermore, active volcanoes have an intense impact on the stratosphere, the second layer of the atmosphere. Gases released from the eruption convert sulfur dioxide to sulfuric acid, which condenses in the stratosphere (Monroe, Wicander, & Hazlett, 2006). This greenhouse gas traps heat in the atmosphere. Volcanoes produce sulfate aerosols, which affect the surface temperature of the earth. A volcanic eruption promotes chemical reactions that alter chlorine and nitrogen which destroys the ozone layer. Moreover, hydrogen chloride and hydrogen fluoride are released by volcanic activity and dissolved in water droplets in steam clouds (Monroe, Wicander, & Hazlett, 2006). This creates acid rain that will fall to the earth, harming plants, marine life, and infrastructure.

Without a doubt, volcanic eruptions are among the most spectacular natural phenomena to occur on our planet. At the same time, however, they are extremely dangerous events to humans. In addition, they pose serious adverse environmental effects.