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  2. Atmospheric circulation - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_circulation

    At the 60th parallel, the air rises to the tropopause (about 8 km at this latitude) and moves poleward. As it does so, the upper-level air mass deviates toward the east. When the air reaches the polar areas, it has cooled by radiation to space and is considerably denser than the underlying air. It descends, creating a cold, dry high-pressure area.

  3. Pressure system - Wikipedia

    en.wikipedia.org/wiki/Pressure_system

    A low-pressure area is a region where the atmospheric pressure at sea level is below that of surrounding locations. Low-pressure systems form under areas of wind divergence that occur in the upper levels of the troposphere. [1] The formation process of a low-pressure area is known as cyclogenesis. [2]

  4. Low-pressure area - Wikipedia

    en.wikipedia.org/wiki/Low-pressure_area

    In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. It is the opposite of a high-pressure area . Low-pressure areas are commonly associated with inclement weather (such as cloudy, windy, with possible rain or storms), [ 1 ] while high-pressure areas are ...

  5. Atmospheric convection - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_convection

    Atmospheric convection is the vertical transport of heat and moisture in the atmosphere.It occurs when warmer, less dense air rises, while cooler, denser air sinks. This process is driven by parcel-environment instability, meaning that a "parcel" of air is warmer and less dense than the surrounding environment at the same altitude.

  6. Convection - Wikipedia

    en.wikipedia.org/wiki/Convection

    The pressure at the bottom of a submerged object then exceeds that at the top, resulting in a net upward buoyancy force equal to the weight of the displaced fluid. Objects of higher density than that of the displaced fluid then sink. For example, regions of warmer low-density air rise, while those of colder high-density air sink.

  7. Thermal low - Wikipedia

    en.wikipedia.org/wiki/Thermal_low

    As the temperature of the surface of the land rises, the land heats the air above it. The less dense warm air rises, which lowers the sea level pressure by about 0.2%. The cooler air above the sea, with higher sea level pressure, flows towards the land into the area of lower pressure, creating a cooler breeze near the coast.

  8. Subsidence (atmosphere) - Wikipedia

    en.wikipedia.org/wiki/Subsidence_(atmosphere)

    By contrast, warm air becomes less dense and moves upwards (atmospheric convection). [ 2 ] Atmospheric subsidence generally creates a high-pressure area as more air moves into the same space: the polar highs are areas of almost constant subsidence, as are the horse latitudes , and the areas of subsidence are the sources of much of the ...

  9. Warm front - Wikipedia

    en.wikipedia.org/wiki/Warm_front

    The warm air mass behind a warm front is not only warmer, but often (but not always) also higher in humidity than the colder air preceding it. Because of a warm air mass’s higher temperature and thus lesser density, mixing between the two air masses is unlikely. Being light, the warm air mass is unable to displace the cooler air mass and ...