Open AccessMadden‐Julian Oscillation in the tropical stratosphere
Author(s) -
Weare Bryan C.
Publication year - 2010
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2009jd013748
Subject(s) - madden–julian oscillation , stratosphere , troposphere , quasi biennial oscillation , climatology , atmospheric sciences , anticyclone , northern hemisphere , zonal and meridional , southern hemisphere , geology , environmental science , meteorology , convection , physics
Links are sought between Madden‐Julian Oscillation (MJO)‐related variations in the troposphere and stratospheric winds, temperature, and ozone. Tropospheric variations of equatorial MJO‐filtered 200 hPa zonal winds define indices of MJO activity for two equatorial regions in the Indian and Western Pacific oceans. These indices are used to calculate composite means of MJO filtered winds, temperature, and ozone mixing ratio for eight height levels from the upper troposphere well into the stratosphere. Strong evidence is presented for significant and coherent MJO departures throughout the lower stratosphere. At 100 hPa, these departures show easterlies in the equatorial regions of the compositing centers and nearly symmetric anticyclonic centers at 25° poleward of those centers, which are associated with significant negative departures in both temperature and ozone mixing ratio. Near 40°N MJO departures of meridional velocity, temperature, and ozone mixing ratio generally tilt westward with height. The most important aspects of these features propagate eastward at a rate of about 5 m/s in the Eastern Hemisphere and several times faster in the Western Hemisphere.