Generally, a measure of the departure of the mean daily temperature from a given standard, one degree day for each degree (

A class of instruments employed to determine the electric potential at a point in the atmosphere, and ultimately the atmospheric electric field.

The atmospheric pressure at the level of the barometer. May or may not be the same as station pressure.

The writing component of a recording instrument.

A halo consisting of a faint white circle passing through the Sun and running parallel to the horizon for as much as 360

Wind with a speed between 28 and 33 knots (32 and 38 mph); Beaufort scale number 7.

The total electromagnetic radiation emitted by the sun. About 99.9 percent of its energy output falls within the wavelength interval from 0. 15 microns to 4.0 microns, with peak intensity near 0.47 microns. About one-half of the total energy in the solar ...

A system of physical units based on the use of the centimeter, gram. and the second as elementary quantities of length. mass. and time.

A fabric cone attached to a metal ring and used to indicate wind direction. often at airfields.

Generally, the relative states of inflow, outflow, and storage of moisture over a given area of earth's surface.

The height ascribed to the lowest layer of clouds or obscuring phenomena when it is reported as broken, overcast, or obscuration and not classified as "thin" or "partial." The ceiling is termed unlimited when these conditions are not satisfied. ...

Moisture contained in the soil above the water table, including water vapor which is present in the soil pores. In some cases this term refers strictly to the humidity contained in the root zone of plants.

An instrument for measuring the extinction coefficient in water.

An instrument for rapidly obtaining samples of airborne dust; a type of dust counter. Particles pass through a cylindrical chamber, are drawn at high velocity through a narrow slit, and then impinge upon a microscope cover glass located a short distance f ...

Thermometer used for measuring the lowest temperature attained during a given interval of time, for example, a day.

Temperature assumed by an unsaturated air parcel when brought adiabatically to a standard pressure (1,000 mb).

See radiation shield.

A type of cistern barometer in which the level of mercury in the cistern is adjusted to the zero point of the scale before each reading.

An instrument which indicates the presence of dust particles in the atmosphere. Also spelled coniscope.

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 ...