South Pacific High

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Sketch showing the normal location of the Pacific High west of Peru and Chile Clima de Chile.JPG
Sketch showing the normal location of the Pacific High west of Peru and Chile

The South Pacific High is a semi-permanent subtropical anticyclone located in the southeast Pacific Ocean. The area of high atmospheric pressure and the presence of the Humboldt Current in the underlying ocean make the west coast of Peru and northern Chile extremely arid. The Sechura and Atacama deserts, as the whole climate of Chile, are heavily influenced by this semi-permanent high-pressure area. This high-pressure system plays a major role in the El Niño–Southern Oscillation (ENSO), and it is also a major source of trade winds across the equatorial Pacific. [1]

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<span class="mw-page-title-main">Upwelling</span> Replacement by deep water moving upwards of surface water driven offshore by wind

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<span class="mw-page-title-main">Atmospheric circulation</span> Process which distributes thermal energy about the Earths surface

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<span class="mw-page-title-main">Climate of Argentina</span> Climate of the country

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<span class="mw-page-title-main">North Pacific High</span> Weather phenomenon off the California coast

The North Pacific High is a semi-permanent, subtropical anticyclone located in the northeastern portion of the Pacific Ocean, located northeast of Hawaii and west of California. It is part of the great belt of anticyclones known as the subtropical ridge. It is strongest during the northern hemisphere summer and shifts towards the equator during the winter, when the Aleutian Low becomes more active. It is responsible for California's typically dry summer and fall and typically wet winter and spring, as well as Hawaii's year-round trade winds.

<span class="mw-page-title-main">Tuvalu Meteorological Service</span>

The Tuvalu Meteorological Service (TMS) is the principal meteorological observatory of Tuvalu and is responsible for providing weather services to the islands of Tuvalu. A meteorological office was established on Funafuti at the time the islands of Tuvalu were administered as parts of the Gilbert and Ellice Islands colony of the United Kingdom. The meteorological office is now an agency of the government of Tuvalu.

<span class="mw-page-title-main">Subtropical Cyclone Katie</span> South Pacific subtropical cyclone in 2015

Subtropical Cyclone Katie, unofficially named by researchers, was an unusual weather event in early 2015. After the 2014–15 South Pacific cyclone season had officially ended, a rare subtropical cyclone was identified outside of the basin near Easter Island, during early May, and was unofficially dubbed Katie by researchers. Katie was one of the few tropical or subtropical systems ever observed forming in the far Southeast Pacific, outside of the official basin boundary of 120°W, which marks the eastern edge of RSMC Nadi's and RSMC Wellington's warning areas, during the satellite era. Due to the fact that this storm developed outside of the official areas of responsibility of the warning agencies in the South Pacific, the storm was not officially included as a part of the 2014–15 South Pacific cyclone season. However, the Chilean Navy Weather Service issued High Seas Warnings on the system as an extratropical low.

<span class="mw-page-title-main">Westerly wind burst</span>

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<span class="mw-page-title-main">Pacific Meridional Mode</span> Climate mode in the North Pacific

Pacific Meridional Mode (PMM) is a climate mode in the North Pacific. In its positive state, it is characterized by the coupling of weaker trade winds in the northeast Pacific Ocean between Hawaii and Baja California with decreased evaporation over the ocean, thus increasing sea surface temperatures (SST); and the reverse during its negative state. This coupling develops during the winter months and spreads southwestward towards the equator and the central and western Pacific during spring, until it reaches the Intertropical Convergence Zone (ITCZ), which tends to shift north in response to a positive PMM.

<span class="mw-page-title-main">Effects of the El Niño–Southern Oscillation in Australia</span>

Effects of the El Niño–Southern Oscillation in Australia is present across most of Australia, particularly the north and the east, and is one of the main climate drivers of the country. Associated with seasonal abnormality in many areas in the world, Australia is one of the continents most affected and experiences extensive droughts alongside considerable wet periods that cause major floods. There exist three phases — El Niño, La Niña, and Neutral, which help to account for the different states of ENSO. Since 1900, there have been 27 El Niño and 18 La Niña events in Australia. The events usually last for 9 to 12 months, but some can persist for two years, though the ENSO cycle generally operates over a time period from one to eight years.

References

  1. E. Linacre; B. Geerts (August 1998). "The South Pacific High, ocean currents, and El Niño". University of Wyoming . Retrieved 13 May 2019.