Weather Display
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Columbia Weather Systems, Inc.
Reference
Glossary
Aspirating Radiation Shield
A device used to shield a sensor such as a temperature probe from direct
and indirect radiation and rain while providing access for ventilation.
Barometric Pressure
The pressure exerted by the atmosphere as a consequence of
gravitational attraction exerted upon the “column” of air lying directly above
the point in question.
Celsius Temperature Scale
A temperature scale with the ice point at 0 degrees and the boiling point of
water at 100 degrees.
Dew Point
The temperature to which a given parcel of air must be cooled at constant
pressure and constant water-vapor content in order for saturation to occur.
When this temperature is below 0°C, it is sometimes called the frost point.
Density Altitude
Density altitude is a meteorological variable that is important to pilots,
especially during the summer. The density altitude is the altitude in a
standard atmosphere where the density is the same as the given
atmospheric density. During a hot muggy summer day, a pilot begins take
off from an airport with an elevation of 2500 feet. Because of the warm
temperature and the moisture in the air, the airplane has to work as if it
was taking off at an airport at an elevation of 6000 feet resulting in the
plane needing more power and a longer roll down the runway to take off.
Fahrenheit Temperature Scale
A temperature scale with the ice point at 32 degrees and the boiling point
of water at 212 degrees.
Global Radiation
The total of direct solar radiation and diffused sky radiation received by a
unit horizontal surface. Global radiation is measured by a Pyranometer.
