Antarctic oscillation
Encyclopedia
The Antarctic oscillation (AAO, to distinguish it from the Arctic oscillation
or AO) is a low-frequency mode of atmospheric variability of the southern hemisphere. It is also known as the Southern Annular Mode (SAM) or Southern Hemisphere
Annular Mode (SHAM).
Arctic oscillation
The Arctic oscillation or Northern Annular Mode/Northern Hemisphere Annular Mode is an index of the dominant pattern of non-seasonal sea-level pressure variations north of 20N latitude, and it is characterized by pressure anomalies of one sign in the Arctic with the opposite anomalies centered...
or AO) is a low-frequency mode of atmospheric variability of the southern hemisphere. It is also known as the Southern Annular Mode (SAM) or Southern Hemisphere
Southern Hemisphere
The Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...
Annular Mode (SHAM).
See also
- North Atlantic oscillationNorth Atlantic oscillationThe North Atlantic oscillation is a climatic phenomenon in the North Atlantic Ocean of fluctuations in the difference of atmospheric pressure at sea level between the Icelandic low and the Azores high. Through east-west oscillation motions of the Icelandic low and the Azores high, it controls the...
- Arctic oscillationArctic oscillationThe Arctic oscillation or Northern Annular Mode/Northern Hemisphere Annular Mode is an index of the dominant pattern of non-seasonal sea-level pressure variations north of 20N latitude, and it is characterized by pressure anomalies of one sign in the Arctic with the opposite anomalies centered...
- Pacific decadal oscillationPacific decadal oscillationThe Pacific Decadal Oscillation is a pattern of Pacific climate variability that shifts phases on at least inter-decadal time scale, usually about 20 to 30 years. The PDO is detected as warm or cool surface waters in the Pacific Ocean, north of 20° N...
- AnticycloneAnticycloneAn anticyclone is a weather phenomenon defined by the United States' National Weather Service's glossary as "[a] large-scale circulation of winds around a central region of high atmospheric pressure, clockwise in the Northern Hemisphere, counterclockwise in the Southern Hemisphere"...
- John Michael WallaceJohn Michael WallaceJohn Michael Wallace is a professor of Atmospheric Sciences at the University of Washington, as well as the former director of the Joint Institute for the Study of the Atmosphere and Ocean --a joint research venture between the University of Washington and the National Oceanic and Atmospheric...
External links
- http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/aao/aao.loading.shtml
- http://stratus.astr.ucl.ac.be/textbook//pdf/Chapter_5.pdf (chapter 5.2.3)
- Animation of Southern Annular Mode in Victoria, Australia
- The Southern Annular Mode Introduction to climate dynamics and climate modelling, Université catholique de Louvain