The planetary waves in total ozone over Antarctica

A significant negative correlation exists between June–August sea surface temperatures (SSTs) in the eastern equatorial Pacific and 15–31 October total ozone values at South Pole, Antarctica. SSTs in the eastern equatorial Pacific were anomalously warmer by 0.67 °C during 1976–1987 compared with 1962–1975. Quasi-biennial oscillation (QBO) easterly winds in the equatorial Pacific stratosphere were generally stronger after 1975 than they were before that time. Prior to the early-to-mid 1970s the trend in global ozone was generally upward, but then turned downward. Total ozone at Hawaii and Samoa, which had been decreasing at a rate of about 0.35% yr−1 during 1976–1987, showed recovery to mid-1970s values in 1988–1989 following a drop in SSTs in the eastern equatorial Pacific to low values last observed there prior to 1976. During 15–31 October 1988, total ozone at South Pole, which had decreased from about 280 Dobson units (DU) prior to 1980 to 140 DU in 1987, suddenly recovered to 250 DU, though substantial ozone depletion by heterogeneous photochemical processes involving polar stratospheric clouds was still evident in the South Pole ozone vertical profiles. These observations suggest that the downward trend in ozone observed over the globe in recent years may have been at least partially meteorologically induced, possibly through modulation by the warmer tropical Pacific ocean waters of QBO easterly winds at the equator, of planetary waves in the extratropics, of the interaction of QBO winds and planetary waves, and of Hadley Cell circulation. A cursory analysis of geostrophic wind flow around the Baffin Island low suggests a meteorological influence on the observed downward trend in ozone over North America during the past decade. Because ozone has a lifetime that varies from minutes to hours in the primary ozone production region at high altitudes in the tropical stratosphere to months and years in the low stratosphere, changes in atmospheric dynamics have the potential for not only redistributing ozone over the globe, but also changing global ozone abundance.

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Zonal wave numbers 1-5 in planetary waves from the TOMS total ozone at 65° S

Annales Geophysicae ◽

10.5194/angeo-23-1565-2005 ◽

2005 ◽

Vol 23 (5) ◽

pp. 1565-1573 ◽

Cited By ~ 17

Author(s):

A. Grytsai ◽

Z. Grytsai ◽

A. Evtushevsky ◽

G. Milinevsky ◽

N. Leonov

Keyword(s):

Total Ozone ◽

General Circulation ◽

Middle Atmosphere ◽

Polar Vortex ◽

Planetary Waves ◽

Wave Number ◽

Stratospheric Polar Vortex ◽

Term Change ◽

Wave Numbers ◽

The Difference

Abstract. Planetary waves in the total ozone at the southern latitude of 65° S are studied to obtain the main characteristics of the zonal wave numbers 1–5. The TOMS total ozone data were used to analyze the amplitude and periodicity variations of the five spectral components during August-December of 1979–2003. A presence of the shorter period of waves 1–3 in 1996 (7 days) in comparison with 2002 (8–12 days) is revealed which can be attributed to the distinction in conditions of typical and anomalously weak stratospheric polar vortex, probably, a strong and weak mean zonal wind. The interannual variations of the monthly and 5-month mean amplitudes of the zonal wave numbers 1–5 are described. Wave 1 has the largest amplitude in October (up to 139 DU in 2000) and increasing amplitude trend (15 DU/decade for October 1979–2003). The 5-month mean amplitudes averaged over 1979–2003 are 53.6, 29.9, 15.5, 10.5, and 7.8 DU for the wave number sequence 1, 2, 3, 4 and 5, respectively. For the stationary components the amplitudes are 38.3, 4.8, 1.8, 1.2, 0.7 DU, respectively. Thus, the stationary component of wave 1 and the traveling one of waves 2–5 are predominant. The tendencies in a long-term change in the wave number amplitude can be explained by taking into account the degree of wave deformation of the stratospheric polar vortex edge, net meridional displacements of the lower stratosphere air, and the difference between the total ozone loss and negative trends in the polar and mid-latitude regions. Keywords. General circulation – Middle atmosphere dynamics – Waves and tides

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Ozone zonal asymmetry and planetary waves characterization during Antarctic spring

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-11-32337-2011 ◽

2011 ◽

Vol 11 (12) ◽

pp. 32337-32361

Author(s):

I. Ialongo ◽

V. Sofieva ◽

N. Kalakoski ◽

J. Tamminen ◽

E. Kyrölä

Keyword(s):

Total Ozone ◽

Climate Models ◽

Travelling Wave ◽

Wave Activity ◽

Planetary Waves ◽

Accurate Estimation ◽

Profile Data ◽

Ozone Monitoring Instrument ◽

Zonal Asymmetry ◽

Ozone Monitoring

Abstract. A large zonal asymmetry of ozone has been observed over Antarctica during winter-spring, when the ozone hole develops. It is caused by a planetary wave-driven displacement of the polar vortex. The total ozone data by OMI (Ozone Monitoring Instrument) and ozone profiles by MLS (Microwave Limb Sounder) and GOMOS (Global Ozone Monitoring by Occultation of Stars) were analysed to characterize the ozone zonal asymmetry and the wave activity during Antarctic spring. Both total ozone and profile data have shown a persistent zonal asymmetry over the last years, which is usually observed from September to mid-December. The largest amplitudes of planetary waves at 65° S (the perturbations can achieve up to 50% of zonal mean) is observed in October. The wave activity is dominated by the quasi-stationary wave 1 component, while the wave 2 is mainly a travelling wave. Wave numbers 1 and 2 generally explain more than the 90% of the ozone longitudinal variations. Both GOMOS and MLS ozone profile data showed that ozone zonal asymmetry covers the whole stratosphere and extends up to the altitudes of 60–65 km. The wave amplitudes in ozone mixing ratio decay with altitude, with maxima (up to 50%) below 30 km. Also the spatio-temporal distributions of the ozone anomaly and the interannual variations were analysed. The characterization of the ozone zonal asymmetry has become important in the climate research. The inclusion of the polar zonal asymmetry in the climate models is essential for an accurate estimation of the future temperature trends. This information might also be important for retrieval algorithms that rely on ozone a priori information.

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Quasi-stationary planetary waves in late winter Antarctic stratosphere temperature as a possible indicator of spring total ozone

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-11-28945-2011 ◽

2011 ◽

Vol 11 (10) ◽

pp. 28945-28967

Author(s):

V. O. Kravchenko ◽

O. M. Evtushevsky ◽

A. V. Grytsai ◽

A. R. Klekociuk ◽

G. P. Milinevsky ◽

...

Keyword(s):

Total Ozone ◽

Large Scale ◽

Stationary Wave ◽

Planetary Waves ◽

Ozone Hole ◽

Late Winter ◽

Stationary Waves ◽

Wave Effects ◽

Antarctic Ozone ◽

Highly Correlated

Abstract. Stratospheric preconditions for the annual Antarctic ozone hole are analysed using the amplitude of quasi-stationary planetary waves in temperature as a predictor of total ozone column behaviour. It is found that the quasi-stationary wave amplitude in August is highly correlated with September–November total ozone over Antarctica with correlation coefficient as high as 0.83 indicating that quasi-stationary wave effects in late winter have a persisting influence on the evolution of the ozone hole during the following three months. Correlation maxima are found in both the lower and middle stratosphere. They are likely manifestations of wave activity influence on chemical ozone depletion and large-scale ozone transport, respectively. Both correlation maxima indicate that spring total ozone tends to increase in the case of amplified activity of quasi-stationary waves in late winter.

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Interannual Changes of Stratospheric Temperature and Ozone: Forcing by Anomalous Wave Driving and the QBO

Journal of the Atmospheric Sciences ◽

10.1175/2011jas3671.1 ◽

2011 ◽

Vol 68 (7) ◽

pp. 1513-1525 ◽

Cited By ~ 3

Author(s):

Murry L. Salby

Keyword(s):

Total Ozone ◽

Planetary Waves ◽

The Arctic ◽

Late Winter ◽

Anomalous Temperature ◽

Quasi Biennial Oscillation ◽

Anomalous Wave ◽

Mean Circulation ◽

Residual Mean Circulation ◽

Observational Record

Abstract A 3D model of dynamics and photochemistry is used to investigate interannual changes of stratospheric dynamical and chemical structure through their dependence on tropospheric planetary waves and on the quasi-biennial oscillation (QBO). The integrations reproduce the salient features of the climate sensitivities of temperature and ozone, which have been composited from the observed records of ECMWF and the Total Ozone Mapping Spectrometer (TOMS). Characterized by a strong anomaly of one sign at polar latitudes and a comparatively weak anomaly of opposite sign at subpolar latitudes, each bears the signature of the residual mean circulation. The structure is very similar to that associated with the Arctic Oscillation. The integrations imply that, jointly, anomalous Eliassen–Palm (EP) flux transmitted from the troposphere by planetary waves and the QBO are the major mechanisms behind interannual changes in the stratosphere. An analogous conclusion follows from the observational record. During early winter, anomalous temperature and ozone are accounted for almost entirely by anomalous EP flux from the troposphere, as they are in the observational record. During late winter, both mechanisms are required to reproduce observed anomalies. Although the QBO forces anomalous structure equatorward of 40°N, the strong anomaly over the Arctic follows principally from anomalous upward EP flux. Reflecting anomalous wave driving of residual mean motion, the change of EP flux leads to anomalous downwelling of ozone-rich air. In concert with isentropic mixing by planetary waves, the anomalous enrichment that ensues at extratropical latitudes sharply modifies total ozone over the Arctic. Integrations distinguished by the omission of heterogeneous processes indicate that chemical destruction accounts for approximately 20% of the anomaly in Arctic ozone between warm and cold winters. Analogous to estimates derived from the observed record of the Solar Backscatter Ultraviolet, version 8 (SBUV-V8) instrument, the remaining approximately 80% follows from anomalous transport. The climate sensitivities of temperature and ozone describe random changes between years, introduced by anomalous EP flux and the QBO. Those interannual changes evolve with a particular seasonality. Like their structure, the seasonal dependence of anomalous temperature and ozone bears the signature of the residual mean circulation. Systematic changes in the observed record, which comprise stratospheric trends, have similar structure and seasonality.

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Interannual Variability and Trends of Extratropical Ozone. Part I: Northern Hemisphere

Journal of the Atmospheric Sciences ◽

10.1175/2008jas2665.1 ◽

2008 ◽

Vol 65 (10) ◽

pp. 3013-3029 ◽

Cited By ~ 15

Author(s):

Xun Jiang ◽

Steven Pawson ◽

Charles D. Camp ◽

J. Eric Nielsen ◽

Run-Lie Shia ◽

...

Keyword(s):

Interannual Variability ◽

Northern Hemisphere ◽

Total Ozone ◽

Climate Model ◽

Principal Component ◽

Planetary Waves ◽

Observation System ◽

Quasi Biennial Oscillation ◽

Total Column Ozone ◽

Column Ozone

The authors apply principal component analysis (PCA) to the extratropical total column ozone from the combined merged ozone data product and the European Centre for Medium-Range Weather Forecasts assimilated ozone from January 1979 to August 2002. The interannual variability (IAV) of extratropical O3 in the Northern Hemisphere (NH) is characterized by four main modes. Attributable to dominant dynamical effects, these four modes account for nearly 60% of the total ozone variance in the NH. The patterns of variability are distinctly different from those derived for total O3 in the tropics. To relate the derived patterns of O3 to atmospheric dynamics, similar decompositions are performed for the 30–100-hPa geopotential thickness. The results reveal intimate connections between the IAV of total ozone and the atmospheric circulation. The first two leading modes are nearly zonally symmetric and represent the connections to the annular modes and the quasi-biennial oscillation. The other two modes exhibit in-quadrature, wavenumber-1 structures that, when combined, describe the displacement of the polar vortices in response to planetary waves. In the NH, the extrema of these combined modes have preferred locations that suggest fixed topographical and land–sea thermal forcing of the involved planetary waves. Similar spatial patterns and trends in extratropical column ozone are simulated by the Goddard Earth Observation System chemistry–climate model (GEOS-CCM). The decreasing O3 trend is captured in the first mode. The largest trend occurs at the North Pole, with values ∼−1 Dobson Unit (DU) yr−1. There is almost no trend in tropical O3. The trends derived from PCA are confirmed using a completely independent method, empirical mode decomposition, for zonally averaged O3 data. The O3 trend is also captured by mode 1 in the GEOS-CCM, but the decrease is substantially larger than that in the real atmosphere.

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