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Climate change (Thesaurus)

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Concept information

Preferred term

Southern Annular Mode  

Definition

  • The leading mode of climate variability of Southern Hemisphere sea level pressure and geopotential height, which is associated with the strength and latitudinal shifts in the mid- to high-latitudes westerly wind belt. The SAM is also known as the Antarctic Oscillation (AAO). A positive SAM phase is defined as lower-than-normal pressures over the polar regions and higher-than-normal pressures in the southern mid-latitudes, with a contraction towards Antarctica and strengthening of the westerly wind belt. The negative SAM phase exhibits positive high-latitude pressure anomalies, negative mid-latitude pressure anomalies and a weaker westerly flow expanded towards the equator. (Source: https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_FullReport.pdf)

Broader concept

Entry terms

  • AAO
  • SAM

In other languages

URI

http://data.loterre.fr/ark:/67375/CHC-TM4HGRSN-C

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