High and Low Pressure Systems Comparison
Subject:
In a high pressure system, an air mass (parcel of air with similar temperature and humidity) cools over an ocean or a cold region inland. This causes the particles in the air mass to lose kinetic energy, and become denser. When the air becomes denser, it contracts and draws in the surrounding air (from the upper troposphere). The atmospheric pressure is then increased by this added weight of the extra air. Because air moves from an area of high pressure to low pressure, this dense air moves outward. Earth?s rotation causes the wind to move clockwise around this high pressure centre. Because of this, the high pressure air sinks and becomes warmer and drier. This means that high pressure systems bring about clear skies.
