英和和英

語源

Perhaps a calque of German Luftmasse.

発音

• (英国発音) IPA^(key): /ˈɛː mas/
• (米国発音) IPA^(key): /ɛəɹ mæs/, /ɛːɹ mæs/

名詞

air mass (複数形 air masses)

1. (meteorology) A particular volume of air, especially one having a roughly uniform temperature, pressure and water vapour content. [from 19th c.]
   • 1939, ‘Cloudburst’, Time, 2 Jan 1939:

     After a 227-day drought ending with December temperatures above 90, a polar air mass collided with a wave of damp tropical air, condensed it in seven days of cloudburst.

   • 2013, Bridie Jabour, The Guardian, 31 Dec 2013:

     The mercury has been soaring in the state since the weekend because of an air mass hovering over Queensland.

語源

air +‎ mass

名詞

airmass (複数形 airmasses)

1. (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.
2. (astronomy) The amount of air through which light from a celestial object passes, normalized to 1 for an object at zenith.
   • 2007, Th. Ratzka et al., “High spatial resolution mid-infrared observations of the low-mass young star TW Hydrae”, in Astronomy and Astrophysics, volume 471, DOI:10.1051/0004-6361:20077357:

     Unfortunately, the extinction is very sensitive to the airmass […]

参考

• air mass classification
• airmass source region

Source: FM 3-6 Field Behavior of NBC Agents.

アナグラム

• Marissa, Massari