Westerlies and polar easterlies meet me in st

Global Wind Patterns: wind belts of the general circulation

Prevailing winds are winds that blow predominantly from an individual direction over a . Like trade winds and unlike the westerlies, these prevailing winds blow from the east to the west, and are often weak and irregular. Moisture is removed by orographic lift, leaving drier air (see katabatic wind) on the descending and. Air mass intrusions from the tropics can be trapped at polar latitudes and .. from winter westerlies to summer easterlies that occurred during the final . [Manney et al., a] occurred in mid‐March (see section ). McIntyre, M. E., and T. N. Palmer (), The surf zone in the stratosphere, J. Atmos. These are the polar easterlies, which come into contact with the warmer air of the They did not find a definite 'shift' in the westerly circulation, but suggest a .. ME.,. Ramos. VA. A review of Late Cretaceous to Quaternary of Laguna Potrok Aike, southern Patagonia (Santa Cruz, Argentina).

westerlies and polar easterlies meet me in st

When hot air rises, its creating a low-pressure area. Similarly, when the cold air sinks, its creating a high-pressure area. Air is pushed out of high-pressure areas towards low-pressure areas.

Prevailing Winds

The movement of air from high-pressure to low-pressure areas follows a basic worldwide pattern. Wind direction is the direction from which the wind blows.

The prevailing wind is the most frequent wind direction in an area. Monsoons are sudden seasonal reversals in wind direction. They bring heavy rain. This is called the Corioli effect, after Frenchman Gustave-Gaspard de Coriolis who first described the phenomenon.

westerlies and polar easterlies meet me in st

The Coriolis force also affects the rotation of ocean currents. It increases in force from the Equator to the Poles. Hot air rises at the Equator and travels north and south.

westerlies and polar easterlies meet me in st

When it reaches latitude 30 Celsius north and south, known as the horse latitude, it sinks, creating high-pressure areas. Some of this air travels back towards the Equator, and these air flows are known as the trade winds.


They die out at the Equator, creating an area of calm, light winds known as the doldrums. The westerlies are eastward-moving winds that blow from the horse latitudes towards the Poles. At around 60 Celsius north and south they meet the polar easterlies, cold winds that blow out from high-pressure areas at the Poles. The sea is warmed by the sun to a greater depth than the land due to its greater specific heat.

The Mysteries of Earth Science: The World Winds

As the temperature of the surface of the land rises, the land heats the air above it. The warm air is less dense and so it rises.

This rising air over the land lowers the sea level pressure by about 0. The cooler air above the sea, now with higher sea level pressure, flows towards the land into the lower pressure, creating a cooler breeze near the coast.

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The strength of the sea breeze is directly proportional to the temperature difference between the land mass and the sea. At night, the land cools off more quickly than the ocean due to differences in their specific heat values, which forces the daytime sea breeze to dissipate.

If the temperature onshore cools below the temperature offshore, the pressure over the water will be lower than that of the land, establishing a land breeze, as long as an onshore wind is not strong enough to oppose it. The wind flows towards a mountain and produces a first oscillation A.

A second wave occurs further away and higher.

Global Winds: Trade Winds, Westerlies and Polar Easterlies - General Knowledge Today

The lenticular clouds form at the peak of the waves B. Over elevated surfaces, heating of the ground exceeds the heating of the surrounding air at the same altitude above sea level, creating an associated thermal low over the terrain and enhancing any lows which would have otherwise existed, [19] [20] and changing the wind circulation of the region.

In areas where there is rugged topography that significantly interrupts the environmental wind flow, the wind can change direction and accelerate parallel to the wind obstruction.

westerlies and polar easterlies meet me in st

Jagged terrain combines to produce unpredictable flow patterns and turbulence, such as rotors. Strong updraftsdowndrafts and eddies develop as the air flows over hills and down valleys. Wind direction changes due to the contour of the land. If there is a pass in the mountain range, winds will rush through the pass with considerable speed due to the Bernoulli principle that describes an inverse relationship between speed and pressure.