Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

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Tragedy at Armero
When the Nevado del Ruiz volcano erupted on November 13, 1985, a lahar caused by the eruption swept down the Lagunillas River and killed 22,000 people in the town of Armero.

The eruption was expected, monitoring was ongoing, and officials had been warned that an eruption was likely. A hazard map was available that correctly portrayed the risk to Armero.

Arial photo of the lahar
that destroyed
the town of Armero.
During a previous eruption in 1845, a lahar had swept down the mountain, killing approximately 1,000 people at the present-day location of Armero. With this evidence, the tragedy at Armero should not have happened. A failure in disaster communications was largely to blame.

A Success Story in Iceland
A volcanic eruption on September 29, 1996, beneath the Vatnajoekull icecap on Iceland melted about three cubic kilometers of ice. Monitoring equipment detected the event, and through past experience, scientists were able to predict that a large outburst flood would occur along the Skeidarˆ River. When the outburst, or "jokulhlaup," occurred on November 5, the Skeidarˆ briefly became the second largest river in the world. Although damages to bridges, roads, and utilities totaled some $15 million, no lives were lost.

Monitoring Mt. St. Helens
When Mt. St. Helens awoke on March 20, 1980, with a small earthquake near the mountain, volcanologists responded with increased monitoring. As seismicity, gas emissions, and a growing bulge on the flank of the volcano were accompanied by small steam and ash eruptions, monitoring was increased and restricted zones around the mountain were defined.

As luck would have it, a map for Mt. St. Helens had recently been completed, and this was used for many decisions. Some zones were totally evacuated, while restricted access was allowed to others. Reservoir levels were decreased, and a well-defined information flow was put into place. When the cataclysmic eruption occurred on May 18, it caused widespread devastation and the loss of 68 lives. The economic loss exceeded $1.8 billion. Without hazard maps and monitoring, both human and economic losses would have been much greater.



"Volcanoes" is inspired by programs from Earth Revealed.


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