A device for measuring the height of tide. It may be simply a graduated staff in a sheltered location where visual observations can be made, or it may consist of an elaborate recording instrument (sometimes called a marigraph) making a continuous graphic ...

See approximate absolute temperature scale, Celsius temperature scale, centigrade temperature scale, Fahrenheit temperature scale, Kelvin temperature scale, Rankine temperature scale, Reaumur temperature scale,

See sea-water thermometer, reversing thermometer.

Same as rain-intensity gauge.

The ratios, to the mean wind speed, of the average magnitudes of the component fluctuations of the wind along three mutually perpendicular axes.

The probability distribution of random errors, typically a normal distribution with a zero mean.

A photometric unit of illuminance or illumination equal to one lumen per square centimeter.

Same as river gauge.

The difference between the solar radiation directed downward and upward; net flux of solar radiation.

The average temperature of the air as indicated by a properly exposed thermometer for a given time period, usually a day, a month, or a year.

A component of a radiosonde consisting of a series of alternate electrically conducting and insulating strips. As these are scanned by a contact the radiosonde transmits temperature and humidity signals alternately. The contact may be a baroswitch as in t ...

An instrument which automatically determines the size distribution of raindrops.

Temperarure at which a liquid solidifies under any given set of conditions. It may or may not be the same as the melting point or the more rigidly defined true freezing point or (for water) ice point.

Operation mode of a communication circuit in which each end can simultaneously transmit and receive.

Instrument for measuring the depth of water from precipitation that is assumed to be distributed over a horizontal, impervious surface and not subject to evaporation.

A small pointer extending downward from the top of the cistern of a Fortin barometer. The level of the mercury in the cistern is adjusted so that it just comes in contact with the end of the pointer, thus setting the zero of the barometric scale.

A pyrheliometer of the thermoelectric type. Radiation is allowed to fall on two concentric silver rings, the outer covered with magnesium oxide and the inner covered with lamp black. A system of thermocouples (thermopile) is used to measure the temperatur ...

The difference between downward and upward (total) radiation; net flux of all radiation.

Based upon damage patterns, classifies twisters into six categories of wind speed (F0 thru F5), ranging from 40 to 318 mph estimated wind speed.

A wind scale adapted by the U.S. Forest Service for use in the forested areas of the northern Rocky Mountains (NRM). It is an adaptation of the Beaufort wind scale. The difference between these two scales lies in the specification of the visual effects of ...