One indirect hazard brought on by a volcanic eruption is global cooling. A massive
eruption can shoot
tephra into the
stratosphere where it is transported around the globe by the
jet stream. The tephra blocks incoming solar radiation cooling the atmosphere until it falls back to the earth.
An example of this occurance was in
Indonsia in 1815. The eruption of Mt. Tambora was the largest known volcanic eruption in human history killing over 10,000 people from direct hazards such as
earthquakes,
landslides, and
tsunamis. The ash cloud was 150 times larger than the cloud produced by the
Mt. St. Helens eruption in 1980. For hundreds of miles surrounding the Indonesian island, days were as dark as night up to 72 hours after the eruption. The cloud of
ash and dust slowly surrounded the globe blocking out incoming
solar energy. The next summer, snow fell in
Boston in June and early frost destroyed crops in
England. 1816 was dubbed by the press as "the year without a summer" and over 82,000 more people died from
starvation as a result of the Mt. Tambora eruption.