-
Abstract:
This paper demonstrates that an annular mode can be constructed from the combination of the North Atlantic Oscillation (NAO) and the Pacific/North American (PNA) patterns. The quasi-annularity, meridional dipole and vertical barotropy of the constructed annular mode resemble those of the Atlantic Oscillation (AO) pattern. It is also a dominant mode in terms of the variance contribution. Moreover, its temporal correlation with the AO is quite strong. This new annular mode has the advantage over the AO in that it incorporates a large portion of the PNA and makes the center of action in the Pacific stronger and more physically relevant than that of the AO. Or, more generally, it may be regarded as a physical mode unlike the AO. The results of this study also indicate the NAO–CPNA perspective contains most of the information of the AO, whereas the AO perspective only contains about half of the information of the NAO-PNA. Consequently, the NAO–CPNA perspective is regarded by the authors to be more comprehensive than that of the AO.
-
References
[1]
|
AMBAUM M H P, HOSKINS B J, STEPHENSON D B.Arctic Oscillation or North Atlantic Oscillation? [J]. J. Climate,2001, 14: 3495-3507. |
[2]
|
DESER C. On the teleconnectivity of the ‘‘ArcticOscillation.’’ [J]. Geophys. Res. Lett., 2000, 27: 779-782. |
[3]
|
FRANZKE C, LEE S, FELDSTEIN S B. Is the NorthAtlantic Oscillation a Breaking Wave? [J]. J. Atmos. Sci., 2004,61: 145-160. |
[4]
|
BENEDICT J J, LEE S, FELDSTEIN S B. Synoptic Viewof the North Atlantic Oscillation [J]. J. Atmos. Sci., 2004, 61:121-144. |
[5]
|
RIVIERE G, ORLANSKI I. Characteristics of the AtlanticStorm-Track Eddy Activity and Its Relation with the NorthAtlantic Oscillation [J]. J. Atmos. Sci., 2007, 64: 241-266. |
[6]
|
THOMPSON D W J, WALLACE J M. The ArcticOscillation signature in the wintertime geopotential height andtemperature fields [J]. Geophys. Res. Lett., 1998, 25:1297-1300. |
[7]
|
THOMPSON D W J, WALLACE J M, Annular modes inthe extratropical circulation. Part I: Month-to-month variability[J]. J. Climate, 2000, 13: 1000-1016. |
[8]
|
THOMPSON D W J, LEE S, BALDWIN M P.Atmospheric Processes Governing the Northern HemisphereAnnular Mode/North Atlantic Oscillation [M]. HURRELL J W,KUSHNIR Y, OTTERSEN G, et al.(Eds.) The North AtlanticOscillation: Climatic Significance and Environmental Impact,2002. |
[9]
|
WALKER G T, BLISS E W. World Weather V [J]. Mem.Roy. Meteor. Soc., 1932: 4: 53-83. |
[10]
|
WALLACE J M, GUTZLER S. Teleconnections in thegeopotential height field during the Northern Hemispherewinter [J]. Mon. Wea. Rev., 1981, 109: 784-812. |
[11]
|
WALLACE J M. North Atlantic oscillation/annular mode:Two paradigms―one phenomenon [J]. Quart. J. Roy. Meteor.Soc., 2000, 126: 791-805. |
[12]
|
WALLACE J M, THOMPSON D W J. The Pacific Centerof Action of the Northern Hemisphere Annular Mode: Real orArtifact? [J]. J. Climate, 2002, 15: 1987-1991. |
-
-
-