Sarychev volcano

Source of the photo
http://earthobservatory.nasa.gov/images/imagerecords/38000/38975/sarychev_omi_2009167_lrg.jpg
Author of the description
Gruiz Katalin

Sarychev Eruption Generates Large Cloud of Sulfur Dioxide.

This image shows average column sulfur dioxide concentrations between June 10 and 17, 2009. High concentrations of sulfur dioxide stretched westward from the volcano as far as Sakhalin Island and mainland Russia and eastward as far as Alaska. Sulfur dioxide is commonly measured in Dobson Units. If you could compress all of the sulfur dioxide in a column of atmosphere into a single layer at the Earth’s surface and keep the temperature at 0 degrees Celsius, one Dobson Unit would be 0.01 millimeters thick, and it would contain 0.0285 grams of sulfur dioxide per square meter.

Source of description

http://earthobservatory.nasa.gov/NaturalHazards/view.php?id=38975