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

Dihydrogen oxide, molecular formula H2O.

(1) The ratio of the speeds of a chemical reaction at two temperatures differing by 10

The maximum distance, usually horizontally, at which a given object or light source is just visible under particular conditions of transmittance and background luminance.

The difference between temperature measurements taken at two significant levels above the ground. Temperatures at 10 and 40 meters are commonly used.

A common unit used in measurement of atmospheric pressure. Defined as that pressure exerted by a one-inch column of mercury at standard gravity and a temperature of 0'C.

A device for measuring sea-surface waves. It consists of a weighted pole below which a disk is suspended at a depth sufficiently deep for the wave motion associated with deepwater waves to be negligible. The pole will then remain nearly as if anchored to ...

Not a linear function of the relevant variables.

A type of pressure-plate anemometer in which the plate, restrained by a stiff spring, is held perpendicular to the wind. The wind-activated motion of the plate is measured electrically. The natural frequency of this system can be made high enough so that ...

Wind with a speed between 48 and 55 knots (55 and 63 mph), Beaufort scale number 10.

See gust and peak gust.

A wave disturbance in airflow due to some barrier in the flow. i.e. a hill or mountain.

The visibility along an identified runway, determined from a specified point on the runway with the observer facing in the same direction as a pilot using the runway. Compare to runway visible range.

The state of the weather with respect to its effect upon the kindling and spreading of forest fires.

The total infrared radiation emitted from the earth's surface. To be carefully distinguished from atmospheric radiation, effective terrestrial radiation, and insolation.

An instrument used to reveal but not necessarily measure the presence of an electrical quantity. It is used to display the output of a sensing element after suitable amplification and modification. Sometimes called display.

Capacity of a soil or other surface to be penetrated by water sinking into the ground under the force of gravity. It thus expresses the rate of percolation.

The distance or length of flow of the air past a point during a given interval of time.

Same as mercury barometer.

The total of direct solar radiation and diffuse sky radiation received by a unit horizontal surface. Global radiation is measured by pyranometers.