Air pressure affects the weather by influencing the movement of air around the planet; areas of low pressure generally develop clouds and precipitation, while areas of high pressure tend to bring clear, sunny weather conditions. Air pressure refers to the force exerted by the atmosphere on the surface of the Earth.Continue Reading
The atmosphere is an ocean of gases that circulate above the planet's surface. It contains tiny, randomly moving air particles that exert their weight above a given area, known as atmospheric pressure or air pressure. Air pressure is inversely proportional to altitude. The higher the elevation, the lower the air pressure. Conversely, the nearer to the Earth's surface, the greater the air pressure. At sea level, the standard atmospheric pressure is given as 1031 hectopascals. Air pressure, along with geography, temperature and humidity, are some of the factors that drive particular weather conditions.
Areas of low pressure are caused by rising warm air while areas of high pressure result from descending cold air. On weather maps, low and high pressure systems are identified using isobars, which are lines connecting places having equal pressures at sea level. When a low pressure system, or a depression, develops over a region, the ascending warm air cools. When it reaches saturation point, the cooled air forms clouds, often followed by precipitation. Areas of very low pressure tend to have stormy weather. When a high pressure system develops, also known as anticyclone, the descending air dissipates cloud formation and calm, dry weather conditions prevail.Learn more about Rain
Convectional rainfall occurs when the warm air deflected from a landform rises and forms rain clouds. Convectional rainfall is very common in tropical areas as well as areas in southeastern England.Full Answer >
Generally unfavorable weather conditions are associated with a low pressure area. In a low pressure area, the atmospheric pressure is low compared to the pressure of nearby areas, and the air tends to be unstable.Full Answer >
Bulk flow is a movement of molecules from an area of high pressure to an area of low pressure. In cell biology, it refers to the transport of fluids or electrolytes between cells through openings, or pores, between the cells. Toilets and faucets employ mechanisms that utilize bulk flow, as well as the transport systems found in plants and animals.Full Answer >
Typhoons form in the tropical oceans when areas of high pressure rush toward areas of low pressure, which creates wind. When the storm begins to rotate and organize around an "eye" of low pressure, it is well on its way to becoming a typhoon. Storms are categorized as typhoons when they reach wind speeds of 74 miles per hour.Full Answer >