air mass
/ˈɛː mas/
Frequency: 4.75 in modern English
Meaning
noun
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.
noun
The amount of air through which light from a celestial object passes, normalized to 1 for an object at zenith.
Example Sentences
- "Unfortunately, the extinction is very sensitive to the airmass[…]"
Etymology
Regional Pronunciation
- American English: /ɛəɹ mæs/
- British English: /ˈɛː mas/