1. what is atmosphere pressure?

    Atmospheric pressure is the force per unit area exerted into a surface in the atmosphere of Earth (or that of another planet).

  2. What causes it?

The atmosphere pressure is caused by the weight of air above that surface of the earth.

3. How large is it?

Average sea-level pressure is 101.325 kPa (1013.25 mbar, or hPa) or 29.92 inches of mercury (inHg) or 760 millimeters (mmHg).

4. What affects the atmosphere pressure?

  • Altitude

  • As altitude increases, atmospheric pressure decreases.

  • P=ρgH

  • Temperature

  • As the sun heats the ground or ocean, warning them, the air near the ground or ocean warms and becomes less dense As this happens the air begins rising, which lowers the air pressure at the Earth's surface.

  • humidity

  • The air is lighter when the air is humid. This is a result of the fact that water molecules are lighter in weight than air molecules. As humidity increases, the weight of the air decreases.