Noun
(physics, meteorology) a widespread body of air, the properties of which can be identified as: (a) having been established while that air was situated over a particular region of the Earth's surface (airmass source region) and (b) undergoing specific modifications while in transit away from the source region. An air mass is often defined as a widespread body of air that is approximately homogeneous in its horizontal extent, particularly with reference to temperature and moisture distribution; in addition, the vertical temperature and moisture variations are approximately the same over its horizontal extent.
(astronomy) The amount of air through which light from a celestial object passes, normalized to 1 for an object at zenith.
Source: en.wiktionary.org"An unstable airmass continues to produce heavy flurries over parts of the southern highway passes," the warning said. Source: Internet
However, with sufficient airmass instability, upward-growing cumuliform clouds can grow to high towering proportions. Source: Internet
Generally, thunderstorms require three conditions to form: moisture, an unstable airmass, and a lifting force (heat). Source: Internet
The dust haze creates an almost desert conditions in the country during the dominance of the Tropical continental airmass (the harmattan). Source: Internet
The haze is as a result of the dust within the airmass limiting visibility and blocking much of the sun's rays from reaching the earth. Source: Internet
The sun's rays enters into the atmosphere of Nigeria more intense than it does during the presence of the Tropical continental airmass, which contained dust (in form of haze) that reduced the intensity of the sun. Source: Internet