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11 Glossary of Common Terms
TERM
DESCRIPTION
ABSOLUTE AIR PRESSURE
ABSOLUTE
BAROMETRIC
PRESSURE
Absolute air pressure is the air pressure
registered on a barometer without regard
to altitude.
BAROMETER
A barometer is a device that measures the
pressure of the air pushing on it—this
measurement is called the barometric
pressure. We don’t actually feel the
barometric pressure because the air
pressure is pushing equally in every
direction.
BEAUFORT (Bft)
An indicator of wind force strength (not
speed) as it would act on a ship’s sails.
Still commonly in used in some locales to
indicate wind force.
DEW POINT
The temperature to which air must be
cooled to become saturated with water
vapor. When further cooled, the airborne
water vapor will condense to form liquid
water (dew), or frost if below freezing.
HEAT INDEX
The heat index (HI) or humiture is an
index that combines air temperature and
relative humidity, in shaded areas, as an
attempt
to
determine
the
human-perceived equivalent temperature,
as how hot it would feel if the humidity
were some other value in the shade.
HECTOPASCALS (hPa)
This is an international standard (SI
system) for measuring air pressure. It
used to be referred to as milli-bar (mb)
and sometimes still is. They are
equivalent.
