High pressure area - Citizendia

The letter used to represent a High pressure area

A high pressure area (also called a high or high-pressure) is a region where the atmospheric pressure is greater than surrounding areas. In the northern hemisphere high pressure areas move clockwise, whereas they move counter-clockwise in the southern hemisphere. In some countries, these regions may be referred to as anticyclones. In Meteorology, an anticyclone (that is opposite to a Cyclone) is a Weather phenomenon in which there is a descending movement of the air and Highs are frequently associated with light winds and subsidence. Subsidence in the Earth's atmosphere is most commonly caused by cold temperatures as air cools it becomes denser and moves towards the ground just as warm air becomes less Subsidence will generally evaporate most cloud droplets after less than 500 meters by adiabatic heating. This article covers adiabatic processes in Thermodynamics. For adiabatic processes in Quantum mechanics, see Adiabatic process (quantum mechanics Thus, high pressure typically brings clear skies. During the day, since no clouds are present to reflect sunlight or reflected inki, there is more incoming shortwave solar radiation and temperatures are higher in the summer and lower in the winter. At night, the absence of clouds means that outgoing longwave radiation (i. Outgoing Longwave Radiation (OLR is the energy leaving the earth as infrared radiation at low Energy. e. heat energy from the surface) is not absorbed, giving cooler diurnal low temperatures in all seasons. Diurnal temperature variation is a Meteorological term that relates to the variation in Temperature that occurs from the highs of the Day to the cool of

Climatologically, high pressure forms at the Horse Latitudes as a result of air which has been uplifted at the equator. Climatology (from Greek grc κλίμα klima, "region zone" and grc -λογία -logia) is the study of Climate, scientifically This article refers to the geographical area For other uses see Horse latitudes (disambiguation Horsey latitudes or Subtropical High The equator (sometimes referred to colloquially as "the Line") is the intersection of the Earth 's surface with the plane perpendicular to the As the hot air rises it cools losing moisture, it is then transported poleward, and then descends creating the high pressure area. This is also known as Hadley Cell circulation. The Hadley cell is a circulation pattern that dominates the tropical atmosphere with rising motion near the equator poleward flow 10-15 kilometers above the surface descending motion Many of the world's deserts are associated with these climatological high pressure systems. A desert is a Landscape or region that receives very little precipitation. Surface high pressure systems tend to be larger in area and have weaker surface winds than low pressure systems, because of to the addition of surface friction to the pressure gradient and coriolis effect that drives the circulation. In physics the Coriolis effect is an apparent deflection of moving objects when they are viewed from a Rotating frame of reference.

Some high pressure areas persist long enough that they acquire names. The land-based Siberian High often remains quasi-stationary for more than a month during the most frigid time of the year, making it unique in that regard. The Siberian High is a massive collection of cold or very cold dry air that accumulates on the Eurasian terrain for much of the year In the United States the Azores High, also known as the Bermuda High, brings fair weather over much of the North Atlantic Ocean. The United States of America —commonly referred to as the The Azores High, also known as the Bermuda High in the United States, is a large subtropical semi-permanent centre of high atmospheric pressure Along its southerly periphery, the clockwise circulation often impels easterly waves across the ocean towards North America during the hurricane season. Tropical waves, or easterly waves, also known as African easterly waves in the Atlantic region are a type of Atmospheric trough, A tropical cyclone is a storm system characterized by a low pressure center and numerous Thunderstorms that produce strong winds and Flooding

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