Magellan 420 Weather Station
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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.
Fahrenheit Temperature Scale
A temperature scale with the ice point at 32 degrees and the boiling point
of water at 212 degrees.
Heat Index
The heat index or apparent temperature is a measure of discomfort due
to the combination of heat and high humidity. It was developed in 1979
and is based on studies of evaporative skin cooling for combinations of
temperature and humidity.
Relative Humidity
Popularly called humidity. The ratio of the actual vapor pressure of the
air to the saturation vapor pressure.
