Definition of air mass in US English:

air mass

noun

Meteorology
  • A body of air with horizontally uniform temperature, humidity, and pressure.

    • ‘The path taken by a cold air mass largely determines the location of a snowfall, and occasionally a northward-moving pool will bring snow along the Great Divide as far north as southern Queensland.’
    • ‘Once you get into that rain shadow region, the seeding effect cuts off quite dramatically, because you have a descending air mass and that modifies the cloud structure far more than the cloud seeding ever will do.’
    • ‘As they move eastward, moisture evaporates into the air, making the air mass more like a maritime tropical air mass.’
    • ‘Southwesterly drifts indicate a drier air mass is taking over.’
    • ‘So just for everyone's information: These clouds are formed by the flow of wind across the mountains when the air mass is stable.’
    • ‘During this period, every time a cold air mass from China moves south and the cold front at its leading edge passes over Taiwan, what follows the rains may be a large blanket of sand moving south in the atmosphere.’
    • ‘The cold air mass caused low temperatures along the Pacific coast.’
    • ‘The other process to consider is the temperature of the body that the air mass travels across.’
    • ‘For those who would like a technical explanation, as the sun approaches the horizon, its light has to pass through a greater air mass, including ozone, dust and water vapour.’
    • ‘This keeps the air mass above the continent cold, and in the cold and dark, clouds that contain chlorine can form in the polar stratosphere.’
    • ‘If the pilot is flying in an air mass that is going up enough to overcome the current sink rate of the glider then this particular time interval is not counted when calculating their average speed while sinking gliding.’
    • ‘The anticyclonic ridge strengthened on its northern side (they can also strengthen on the southern side) and interrupted the full force of the colder air mass.’
    • ‘However, because the succeeding anticyclone progresses eastward quickly, the full force of the cold air mass will be thwarted in its northward push.’
    • ‘In summer, the air mass is more turbulent and cloudy.’
    • ‘The air mass bringing the coldest temperatures is the polar continental mass that comes in from the Soviet Union.’
    • ‘The rotating air mass creates a high-pressure system throughout the region.’
    • ‘The big variations come when a new air mass moves in.’
    • ‘Put simply, the appearance of a cloud depends mainly on two things; the stability of the air mass that the cloud forms in, and whether the cloud has ice particles or water droplets within it.’
    • ‘This usually forms when the air mass that is lifted is quite extensive, and can occur in most areas.’
    • ‘The air mass only gives an indication of the type of weather which may occur.’

Pronunciation

air mass

/ˈer mas/