Term
Hygrometer
Inches of Mercury
(inHg)
Rain Gauge
Range
Relative Barometric
Pressure
Resolution
Solar Radiation
Thermometer
Wind Vane
Definition
A hygrometer is a device that measures relative
humidity. Relative humidity is a term used to
describe the amount or percentage of water
vapor that exists in air.
Pressure in Imperial units of measure. 1 inch of
mercury = 33.86 millibars
A rain gauge is a device that measures liquid
precipitation (rain), as opposed to solid
precipitation (snow gauge) over a set period of
time. All digital rain gauges are self emptying
or self dumping (also referred to as tipping rain
gauge). The precision of the rain gauge is based on
the volume of rain per emptying cycle.
Range is defined as the amount or extent a value
can be measured.
Measured barometric pressure relative to your
location or ambient conditions.
Resolution is defined as the number of significant
digits (decimal places) to which a value is being
reliably measured.
A solar radiation sensor measures solar energy
from the sun. Solar radiation is radiant energy
emitted by the sun from a nuclear fusion reaction
that creates electromagnetic energy. The
spectrum of solar radiation is close to that of a
black body with a temperature of about 5800 K.
About half of the radiation is in the visible short-
wave part of the electromagnetic spectrum. The
other half is mostly in the near-infrared part, with
some in the ultraviolet part of the spectrum.
A thermometer is a device that measures
temperature. Most digital thermometers are
resistive thermal devices (RTD). RTDs predict
change in temperature as a function of electrical
resistance.
A wind vane is a device that measures the
direction of the wind. The wind vane is usually
combined with the anemometer. Wind direction is
the direction from which the wind is blowing.
EN
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