Volcanic Eruptions: Mt. Pinatubo vs. Eyjafjallajokull

The Philippines Mount Pinatubo erupted on June 15, 1991.  It's estimated 20 million tons of sulfur dioxide and ash particles blasted more than 12 miles into the stratosphere and circled the Earth for three weeks.  This is the second largest eruption in the 20th century.

 

The 1991 eruption of Mt. Pinatubo ejected 20 megatons of sulfur dioxide into the stratosphere.  The eruption of Mt. Eyjafjallajokull in Iceland is nearly 10,000 times smaller, only adding 0.003-0.004 megatons of sulfur dioxide into the troposphere.

 

Within two weeks, the sulfur dioxide Mount Pinatubo ejected spread around the Earth and took one year to cover the entire planet.  In  1992 and 1993, the average temperature in the Northern Hemisphere was around 1°F and the entire planet was cooled 0.7 to 0.9°F.

 

Mount Pinatubo's 1991 eruption ejected volcanic ash 12 miles into the atmosphere, blocking nearly 10% of our sunlight and cooling the entire planet.  Iceland's Eyjafjalajokull volcano spewed ash up to 3.7 miles into the atmosphere, bringing Europe colorful sunsets.

 

Iceland's Eyjafjallajokull volcano is likely to have little to no impact on global weather because the eruption did not reach the stratosphere.  The rain and winds of the troposphere, not found in the stratosphere, will wash away the volcanic plume as it drifts east.

 

Air primarily enters the stratosphere (about 6-31 miles above the Earth's surface) above the tropics and descends back to the troposphere (about 0-6 miles) at the poles.   Mt. Eyjafjallajokull's high latitude location will keep most of its eruption in the troposphere.