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New Englanders have
a saying: "If you don't like the weather, just wait a minute."
Weather forecasts may be more stable in other parts of the world,
but the basic idea stands. Weather is dynamic, the product of
interacting forces we are only beginning to understand.
Witness the weather extremes caused by El Niño in 1997
and 1998. El Niño raised water temperatures in the Pacific
and the effects were felt worldwide: crop failures, disease
outbreaks, excess snow, or too little
rain. Journalists have painted a picture of El Niño as
an isolated event, a freak weather occurrence. But El Niño,
like many other climatic forces, is part of Earth's balancing
act. It has come before. It will happen again.
Weather may change on a daily basis, but climate changes over
geologic time. The history of the planet is marked by cold periods
and warm periods that are surprisingly regular. Some scientists
suggest that human civilization has thrived in what is no more
than a brief warm spell in Earth's history. Like El Niño,
ice ages are patterns, not incidents. Seen on a geologic scale,
climate is no more stable than weather.
Join us as we explore the forces
behind the weather. Try your hand at tornado chasing or discover
how wind chill works. Begin by taking a look at what protects
Earth from the forbidding climate of outer space in "The
Atmosphere."
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