The standard deviation of a sufficiently large number of measurements of the same quantity by the same instrument or method. The non-correctable part of the inaccuracy of an instrument, it represents the limit of measurement precision. The uncertainty of ...

A graphical representation of stage or discharge at a point on a stream as a function of time.

The rate of decrease of pressure per unit distance at a fixed time.

The physical exposure of an instrument. The effect of immediate environment upon the representativeness of the measurements obtained by meteorological instruments is considerable and not always correctable. The purpose of the instrument shelter is to prov ...

The depth of water that would result from the melting of snow or ice, assuming measurement on a horizontal surface and no infiltration or evaporation.

The programs and instructions which direct a computer.

An instrument for the measurement of both solar and terrestrial radiation.

A protocol similar to RS232 which makes use of differential transmission to provide high speed data transmission over significantly longer distances.

A number of quantity defining a limit that errors will not exceed when a device is used under specified operating conditions. Accuracy rating can be expressed in a number of forms, i.e. in terms of the measured variable (+/- 1 C), percent of span (+/-0.5% ...

Same as rain-intensity gauge.

An anemometer in which the sensor rotation is transmitted to a mechanical counter which directly integrates the air movement past the sensor. Used to determine total air passage (wind run). Average wind speed can be calculated from the difference between ...

Barometer in which pressure is determined by balancing air pressure against the weight of a column of mercury in an evacuated glass tube.

An instrument for the measurement of the rate of ice accretion on an unheated body.

Anemometer which generates an electrical contact output with a frequency proportional to wind speed.

A form of data transmission in which the bits of each character are all sent simultaneously, resulting in extremely fast communication but requiring a communication path for each bit. Compare to serial data transmission.

The center of an area of high pressure, usually accompanied by anticyclonic and outward wind flow. Also known as an anticyclone.

An instrument which records the duration of sunshine and gives a quantitative measure of the amount of sunshine by the action of the sun's rays upon blueprint paper. A type of sunshine recorder.

A reflecting type telescope with a 45

Any sudden and heavy rain, almost always of the shower type.

Physical equipment used in data processing. Compare to firmware, software.