Kelvin wave variability in the upper stratosphere observed in SBUV ozone data. [SBUV (solar backscatter ultraviolet)]

Journal Article · Fri Nov 01 04:00:00 EST 1991 · Journal of the Atmospheric Sciences; (United States)

OSTI ID:5419166

Randel, W J; Gille, J C ^[1]

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1. National Center for Atmospheric Research, Boulder, CO (United States)

The signatures of equatorially trapped Kelvin waves in the upper stratosphere are analyzed in Solar Backscatter Ultraviolet (SBUV) ozone data over the years 1979-86. Comparisons are first made with contemporaneous Limb Infrared Monitor of the Stratosphere (LIMS) ozone data to validate the SBUV Kelvin wave signatures. SBUV and LIMS data both show coherent Kelvin wave oscillations in the upper stratosphere, where ozone is photochemically controlled, and mirrors the temperature fluctuations associated with Kelvin waves; however, SBUV data underestimate wave amplitudes by 20%-60%. Furthermore, transport-induced Kelvin wave patterns in the lower stratosphere are not observed in SBUV data. The eight years of SBUV data reveal the regular occurrence of eastward-propagating zonal wave 1-2 Kelvin waves with periods in the range of 5-15 days. These data show a strong semiannual modulation of Kelvin wave activity, as documented previously in rocketsonde observations. Eight-year-average ensemble spectra are compared to the semiannual oscillation (SAO) in stratospheric zonal winds; a seasonal asymmetry in the strength of Kelvin waves is found, which mimics that observed in the zonal winds. There is a near exact phasing of maxima in wave variance with the strongest easterly zonal winds, i.e., when the wind acceleration is near zero; this argues that Kelvin waves are not a determining factor in the westerly acceleration phase. An exception is found near the stratopause in January when Kelvin wave maxima coincide with strong westerly acceleration. Interannual variability of Kelvin waves is studied in relation to that of the stratospheric zonal winds. No consistent relationship with the quasi-biennial oscillation (QBO) in the lower stratosphere is observed, and correlations with upper stratospheric winds are weak or nonexistent. 35 refs., 11 figs., 1 tab.

• OSTI ID: 5419166
• Journal Information: Journal of the Atmospheric Sciences; (United States), Journal Name: Journal of the Atmospheric Sciences; (United States) Vol. 48:21; ISSN 0022-4928; ISSN JAHSAK
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
540110*
EARTH ATMOSPHERE
GRAVITY WAVES
LAYERS
METEOROLOGY
OZONE
OZONE LAYER
RADIATIONS
SOLAR RADIATION
SPECTRA
STELLAR RADIATION
STRATOSPHERE
TROPICAL REGIONS
ULTRAVIOLET SPECTRA
WAVE PROPAGATION