Annenberg Media Exhibits -- Volcanoes

Volcanoes: Can we predict volcanic eruptions?

Where Should You Build? Is it safe to build
near a volcano? You make the call.

How can we reduce the risk?

There are four general approaches to coping with volcanic hazards. We can try to keep the hazard from occurring--often an impossible task. We can try to alter its path or reduce its impact on existing development. We can take steps to protect future development. We can also do our best to have disaster response plans in place before they are needed.

At Mt. St. Helens,
geologists measure the
distance across a
crack on the crater floor.

Removing the Threat
Obviously, there is no way to stop an eruption. We can, however, attempt to reduce the eruption's effects by reinforcing structures (for example, strengthening roofs to support the weight of tephra deposits) or by building protective works (such as walls to deflect lava flows away from developed areas). Such efforts can be and have been successful, but are of limited use in a large-scale eruption.

Planning for the Future
Protecting future development from volcanic hazards is a simpler task. Before building, we should evaluate the risk. If it seems too great, a safer location should be found. This type of planning is very effective, but all too often, people are drawn to the lush, rolling terrain of a quiet volcano.

Disaster Preparedness
When a volcano comes to life, a few weeks may not be enough time to avert a tragedy. Planning is the key to saving lives. Well before the warning signs occur, people must be educated about volcanic hazards. Evacuation plans must be in place. Communication between scientists, officials, the media, and the general public should be outlined and practiced. Emergency measures must be thought out and agreed upon.

If you doubt the importance of these efforts, take another look at past volcanic tragedies, such as the 1985 eruption of Nevado del Ruiz. Communication failures left the town of Armero unprepared for evacuation. When a deadly mudflow came down the slope, 21,000 people--90 percent of the town's residents--perished.

[Read More About COPING WITH RISK]

"Volcanoes" is inspired by programs from Earth Revealed.