Open AccessBoreal Winter Links between the Madden–Julian Oscillation and the Arctic Oscillation
Author(s) -
Michelle L’Heureux,
R. Wayne Higgins
Publication year - 2008
Publication title -
journal of climate
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.315
H-Index - 287
eISSN - 1520-0442
pISSN - 0894-8755
DOI - 10.1175/2007jcli1955.1
Subject(s) - madden–julian oscillation , climatology , extratropical cyclone , arctic oscillation , geopotential height , teleconnection , oscillation (cell signaling) , environmental science , mode (computer interface) , atmospheric sciences , geopotential , northern hemisphere , convection , geology , precipitation , meteorology , el niño southern oscillation , geography , biology , computer science , genetics , operating system
There is increasing evidence that the Madden–Julian oscillation (MJO) modifies the mid- to high-latitude circulation and, in particular, appears to have a relationship to the leading mode of extratropical variability, the Arctic Oscillation (AO). In this study, new insights into the observed similarities between the MJO and the AO are explored. It is shown that the eastward progression of the convectively active phase of the MJO is associated with a corresponding shift in the tendency and sign of the AO index. Moreover, the AO and the MJO share several analogous features not only in the global circulation, but also in surface temperature fields. Also, the AO is linked to a pattern of eastward-propagating MJO-like variability in the tropics that is partially reproduced in free runs of the NCEP Climate Forecast System (CFS) model. Finally, it is shown that the structure of the AO, as defined by the leading mode in the 1000-hPa geopotential height field, is significantly altered based on the phase of the MJO.