air pressure variations

Air pressure varies due to changes in temperature, altitude, and weather conditions. When the air warms, its molecules spread out, decreasing pressure; cooling causes molecules to contract, increasing pressure. Higher altitudes have lower pressure because there's less air above. Weather systems, like storms, also influence pressure—low pressure often brings clouds and rain, while high pressure usually means clear skies. These variations drive wind movement and impact our climate and weather patterns, making air pressure an essential factor in understanding atmospheric behavior.