Waldbeck Halley - Glossary of Terms

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EN
GLOSSARY OF TERMS
Term Denition
Absolute Barometric
Pressure
Absolute pressure is the measured atmospheric
pressure and is a function of altitude, and to a
lesser extent, changes in weather conditions.
Absolute pressure is not corrected to sea-
level conditions. Refer to Relative Barometric
Pressure.
Accuracy Accuracy is dened as the ability of a
measurement to match the actual value of the
quantity being measured.
Barometer A barometer is an instrument used to measure
atmospheric pressure.
Calibration Calibration is a comparison between
measurements – one of known magnitude or
correctness of one device (standard) and another
measurement made in as similar a way as possible
with a second device (instrument).
Dew Point The dew point is the temperature at which a given
parcel of humid air must be cooled, at constant
barometric pressure, for water vapor to condense
into water. The condensed water is called dew.
The dew point is a saturation temperature. The
dew point is associated with relative humidity.
A high relative humidity indicates that the dew
point is closer to the current air temperature.
Relative humidity of 100% indicates the dew
point is equal to the current temperature and the
air is maximally saturated with water. When the
dew point remains constant and temperature
increases, relative humidity will decrease.
HectoPascals (hPa) Pressure units in SI (international system) units of
measurement. Same as millibars (1 hPa = 1 mbar)