Volcanoes and the Environment

Ozone Effect - When volcanoes erupt, they release many gases that are harmful to the ozone layer.  One such gas in volcanic HCl or hydrochloric acid.  After one eruption in Chile, ozone levels were 15-20% below their normal levels.  The HCl by itself cannot harm the ozone, but when mixed with human CFC’s, it forms a powerful ozone destroyer

Greenhouse Effect- The small amount of CO2 that volcanoes produce is not enough to affect global warming. Volcanoes produce 110 million tons per year, while humans produce 10 billion tons/year.

Haze Effect- This effect is caused by sulfur acid droplets in the stratosphere.  The sulfur that is produced in volcanic eruptions combines with water droplets to form sulfuric acid.  This acid absorbs solar radiation and sends it back into space.  After one large sulfuric eruption, global temperatures dropped 0.5 degrees Celsius. 

Effects of an Eruption

The closer you get to the origin of the lava, the more devastating the surroundings become.  Around the cone, there is little to no vegetation, even 5 years after the eruption.  Some grasses have begun to grow, but the area is still largely barren.

As you move about 200 yards away, many grasses can be seen growing, the in primary succession phase.  Only the hardiest of plants can survive in this soil, and trees are few and far-between.

About 500 yards away, grasses cover the entire ground, and tress are more plentiful.  It will still take many years for this environment to fully recover from the eruption.

Bibliography 
Chasing Lava: A Geologist's Adventures at the Hawaiian Volcano Observatory. Wendell A. Duffield.

Volcanoes in Human History: The Far-Reaching Effects of Major Eruptions. Donald Sanders.

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