Definition

Noun: The force per unit area exerted by the weight of the air in the Earth's atmosphere. It is the pressure caused by the weight of the air above a given point.

Usage

Atmospheric pressure is a fundamental concept in meteorology and physics. It is typically measured with a barometer and is expressed in units such as atmospheres (atm), pascals (Pa), millibars (mb), or inches of mercury (inHg). Standard atmospheric pressure at sea level is approximately 101,325 pascals.

Examples

• The atmospheric pressure drops significantly as you ascend a mountain.
• Meteorologists monitor changes in atmospheric pressure to predict weather patterns.
• A low atmospheric pressure system is often associated with stormy conditions.

Advanced Usage

• "to exert atmospheric pressure": This phrase describes the action of the atmosphere's weight applying force.
  • The air column above us exerts atmospheric pressure on everything at the surface.
• In technical contexts, it is central to concepts like Boyle's law in physics and is a key variable in altimeter settings for aviation.

Variants and Related Words

• Barometric pressure: A synonym often used interchangeably with atmospheric pressure, specifically when measured by a barometer.
• Air pressure: A more general, less technical term for the same phenomenon.
• Low-pressure system / High-pressure system: Meteorological terms describing areas of relatively low or high atmospheric pressure, which drive weather.

Synonyms

• Barometric pressure
• Air pressure

Related Phrases

• Standard pressure: Refers to the standard average atmospheric pressure at sea level, defined as 1 atm or 1013.25 mb.
• Pressure gradient: The rate of change of atmospheric pressure over a given distance, which determines wind speed and direction.

Noun

1. the pressure exerted by the atmosphere