From The Developers...

Specially designed helper pages are also available for important components and concepts, like cold fronts (below). These helpers provide a quick explanation about the topic in question.

Concept Helpers
quick explanation about cold fronts

As with product helpers, content helper pages provide the user with a brief yet informative explanation about the topic in question. These pages are accessible from product helpers or from instructional module pages. An example concept helper about cold fronts has been given below. This helper gives a simple description about cold fronts plus a useful diagram to help the user better visualize what a cold front is.

-- Begin Helper --

A cold front is defined as the transition zone where a cold air mass is replacing a warmer air mass. The air behind a cold front is colder and generally drier than the air ahead of it.

If you were standing outside and a cold front passed through, the air would become cooler and drier than it was before. Occasionally, the temperature can drop as much as 15 degrees in an hour after a cold front comes through.

-- End Helper --

product helpers
Terms for using data resources. CD-ROM available.
Credits and Acknowledgments for WW2010.
Department of Atmospheric Sciences (DAS) at
the University of Illinois at Urbana-Champaign.

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