Volcanic Particles in the Atmosphere

Volcanic particles (tephra) are lofted into the atmosphere by volcanic plumes. The plumes rise because they consist of hot particles and gas and thus are less dense than the atmosphere, much like a hot air balloon.

Many eruption plumes can rise to great heights in the atmosphere, reaching well into Earth's stratosphere. This can result in widespread transport of volcanic particles. Look at the heights of plumes from historic eruptions below.

Mt. St. Helens, located in Washington state, USA, erupted explosively in 1980. The plume sent volcanic ash into the stratosphere and caused significant damage around the flanks of the volcano. Loss of life was relatively low because the area around the volcano was not densely populated.

Krakatau volcano, located in Indonesia, erupted explosively in 1883, producing one of the largest eruptions in historic time. Over 35,000 people were killed, principally by tsunamis that struck the coasts of Java and Sumatra. A large plume was generated that sent volcanic ash well into the stratosphere.

Pinatubo volcano, located in the Philippines, erupted explosively in 1991 after being dormant for more than 600 years. The eruption was one of the largest of the 20th century. A very large plume penetrated well into the stratosphere and volcanic particles were able to completely circle the globe.

Tambora volcano, located in Indonesia, erupted explosively in 1815. The event was the largest eruption of historic times, claiming as many as 91,000 lives. Most people died of starvation as a result of the eruption's impact on the rice crop in Indonesia. The eruption also triggered the collapse of the upper part of the volcano, forming a large caldera.