Same as radiation pattern. Anticyclone-An area of high atmospheric pressure which has a closed circulation that is anticyclonic (clockwise in northern hemisphere and counterclockwise in southern hemisphere).

The lowest temperature that can be obtained on a wet-bulb thermometer in any given sample of air. Obtained by evaporation of water (or ice) from the muslin wick. Used in computing dew point and relative humidity.

Same as recording rain gauge.

The distance that an observer can see vertically into a surface-based obscuring phenomenon such as fog, rain, or snow. The distance estimate must be based upon ceiling balloon ascensions or ceiling light projector measurements.

A mercury barometer in which the tube is U-shaped and the upper and lower mercury surfaces have the same diameter.

A computed characteristic of a particular river basin, expressed as the time difference between the time-center of mass of rainfall and the time-center of mass of resulting runoff.

General term for any device that measures precipitation: principally a rain gauge or snow gauge.

The mass density of a parcel of air expressed in units of mass per volume.

The process whereby a position on the scale of an instrument is identified with the magnitude of the signal (or input force) actuating the instrument.

An area of low barometric pressure, with its attendant system of winds. Also called a depression or cyclone.

Any quantity, such as force velocity, or acceleration, which has both magnitude and direction at each point in space, as opposed to scalar which has magnitude only. Such a quantity may be represented geometrically by an arrow of length proportional to its ...

In a radiosonde observation, a level (other than a standard level) for which values of pressure, temperature, and humidity are reported because temperature and/or humidity data at that level is sufficiently important or unusual to warrant the attention of ...

An instrument which automatically records the voltage applied to it, as a function of time.

Wind with a speed between 7 and 10 knots (8 and 12 mph), Beaufort scale number 3.

A white disk 12" or more in diameter which is lowered into the sea to estimate transparency of the water. The depths are noted at which it first disappears when lowered and reappears when raised.

Same as wave pole.

The interval between the lower and upper measuring limits of an instrument, i.e. a thermometer with a range of -35 to 50

A type of climatic diagram whose coordinates are some form of temperature vs. a form of humidity or precipitation.

An instrument for measuring the pressure of gases and vapors. A mercury barometer is a type of manometer.

A unit of pressure equal to 10' dyne per cm-' (101 barye), 1000 millibars. 29.53 inches of mercury.