Enhancements of the refractory submicron aerosol fraction in the Arctic polar vortex: feature or exception?

Abstract. In situ measurements with a four-channel stratospheric condensation particle counter (CPC) were conducted at up to 20 km altitude on board the aircraft M-55 Geophysica from Kiruna, Sweden, in January through March (EUPLEX 2003, RECONCILE 2010) and in December (ESSenCe 2011). During all campaigns air masses from the upper stratosphere and mesosphere were subsiding inside the Arctic winter vortex, thus initializing a transport of refractory aerosol into the lower stratosphere (Θ < 500 K). The strength and extent of this downward transport varied between the years depending on the dynamical evolution of the vortex. Inside the vortex and at potential temperatures Θ ≥ 450 K around 11 submicron particles per cm3 were generally detected. Up to 8 of these 11 particles per cm3 were found to contain thermo-stable (at 250 °C) residuals with diameters of 10 nm to about 1 μm. Particle mixing ratios (150 mg−1) and fractions of non-volatile particles (75% of totally detected particles) exhibited highest values in air masses having the lowest content of nitrous oxide (70 nmol mol−1 of N2O). This indicates that refractory aerosol originates from the upper stratosphere or the mesosphere. Derived from the mixing ratio of the simultaneously measured long-lived tracer N2O, an empirical index serves to differentiate probed air masses according to their origin: inside the vortex, the vortex edge region, or outside the vortex. Previously observed high fractions of refractory submicron aerosol in the 2003 Arctic vortex were ascribed to unusually strong subsidence during that winter. However, measurements under perturbed vortex conditions in 2010 and during early winter in December 2011 revealed similarly high values. Thus, the abundance of refractory aerosol in the lower stratosphere within the Arctic vortices appears to be a regular feature rather than the exception. During December, the import from aloft into the lower stratosphere appears to be developing; thereafter the abundance of refractory aerosol inside the vortex reaches its highest levels in March. The correlations of refractory aerosol with N2O suggest that, apart from mean subsidence, diabatic dispersion inside the vortex significantly contributes to the transport of particles to the Arctic lower stratosphere. A measurement-based estimate of the total mass of refractory aerosol inside the vortex is provided for each campaign. Based on the derived increase of particle mass in the lower stratospheric vortex (100–67 hPa pressure altitude) by a factor of 4.5 between early and late winter, we estimate the total mass of mesospheric particles deposited over the winter 2009/2010 in the entire Arctic vortex to range between 77 × 103 and 375 × 106 kg. This estimate is compared with the expected atmospheric influx of meteoritic material (110 ± 55 × 103 kg per day). Such estimates at present still hold considerable uncertainties, which are discussed in this article. Nevertheless, the results enable placing constraints on the shape of the so far unknown size distribution of refractory aerosol within the vortex.

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Enhancements of the refractory submicron aerosol fraction in the Arctic polar vortex: feature or exception?

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-9849-2014 ◽

2014 ◽

Vol 14 (7) ◽

pp. 9849-9901

Author(s):

R. Weigel ◽

C. M. Volk ◽

K. Kandler ◽

E. Hösen ◽

G. Günther ◽

...

Keyword(s):

Total Mass ◽

Lower Stratosphere ◽

Heat Exposure ◽

Dynamical Evolution ◽

The Arctic ◽

Late Winter ◽

Air Masses ◽

Submicron Aerosol ◽

Mixing Ratios

Abstract. In situ measurements with a 4-channel stratospheric condensation particle counter (CPC) were conducted at up to 20 km altitude on board the aircraft M-55 Geophysica from Kiruna, Sweden, in January through March (EUPLEX 2003; RECONCILE 2010) and in December (ESSenCe, 2011). During all campaigns air masses from the upper stratosphere and mesosphere were subsiding inside the Arctic winter vortex, thus transporting refractory aerosol into the lower stratosphere (Θ<500 K) by vertical dispersion. The strength and extent of this downward transport varied between the years depending on the dynamical evolution of the vortex. Inside the vortex and at altitudes of potential temperatures Θ ≥ 450 K as many as eight of eleven particles per cm3 contained refractory material, thermally stable residuals with diameters from 10 nm to a few μm which endure heat exposure of 250 °C. Particle mixing ratios (up to 150 refractory particles per milligram of air) and fractions of non-volatile particles (up to 75% of totally detected particles) reach highest values in air masses with lowest content of nitrous oxide (N2O, down to 70 nmol mol−1). This indicates that refractory aerosol originates from the upper stratosphere or the mesosphere. From mixing ratios of the long lived tracer N2O (simultaneously measured in situ) an empirical index was derived which serves to differentiate air masses according to their origin from inside the vortex, the vortex edge region, and outside the vortex. Previously, observed high fractions of refractory submicron aerosol in the 2003 Arctic vortex were ascribed to unusually strong subsidence during that winter. Measurements under perturbed vortex conditions in 2010 and during early winter in December 2011, however, revealed similarly high values. Thus, the abundance of refractory aerosol at high levels appears to be a feature rather than the exception for the Arctic vortices. During December, the import from aloft into the lower stratosphere appears to be developing; thereafter the abundance of refractory aerosol inside the vortex reaches its highest levels until March. A measurement-based estimate of the total mass of refractory aerosol inside the vortex is provided for each campaign. Based on the derived increase of particle mass in the lower stratospheric vortex (100–67 hPa pressure altitude) on the order of 32 × 106 kg between early and late winter and assuming a mesospheric origin, we estimate the total mass of mesospheric particles deposited in the Arctic vortex and compare it to the expected atmospheric influx of meteoritic material (110 ± 55 × 103 kg per day). Such estimates at present still hold considerable uncertainties which are discussed in detail. Nevertheless, the results strongly suggest that the Arctic vortex easily achieves the drainage of all meteoric material deposited on the upper atmosphere.

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Quantifying transport into the Arctic lowermost stratosphere

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-11623-2010 ◽

2010 ◽

Vol 10 (23) ◽

pp. 11623-11639 ◽

Cited By ~ 32

Author(s):

A. Werner ◽

C. M. Volk ◽

E. V. Ivanova ◽

T. Wetter ◽

C. Schiller ◽

...

Keyword(s):

High Latitude ◽

Trace Gases ◽

Polar Vortex ◽

The Arctic ◽

Late Winter ◽

Mass Balance Calculation ◽

Air Masses ◽

History Of ◽

Simple Mass

Abstract. In the Arctic winter 2003, in-situ measurements of the long-lived trace gases N2O, CFC-11 (CCl3F), H-1211 (CBrClF2), CH4, O3 and H2O have been performed on board the high-altitude aircraft M55 Geophysica. The data are presented and used to study transport into the lowermost stratosphere (LMS). The LMS can be regarded as a mixture of fractions of air originating in (i) the troposphere, (ii) the extra-vortex stratosphere above 400 K and (iii) the Arctic vortex above 400 K. These fractions are determined using a simple mass balance calculation. The analysis exhibits a strong tropospheric influence of 50% ± 15% or more in the lowest 20 K of the high-latitude LMS. Above this region the LMS is dominated by air masses having descended from above 400 K. Below the Arctic vortex region at potential temperatures above 360 K, air in the LMS is a mixture of extra-vortex stratospheric and vortex air masses. The vortex fraction increases from about 40% ± 15% at 360 K to 100% at 400 K for equivalent latitudes >70° N. This influence of air masses descending through the bottom of the polar vortex increases over the course of the winter. By the end of winter a significant fraction of 30% ± 10% vortex air in the LMS is found even at an equivalent latitude of 40° N. Since the chemical and dynamical history of vortex air is distinct from that of mid-latitude stratospheric air masses, this study implies that the composition of the mid- to high-latitude LMS during late winter and spring is significantly influenced by the Arctic vortex.

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Quantifying transport into the Arctic lowermost stratosphere

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-9-1407-2009 ◽

2009 ◽

Vol 9 (1) ◽

pp. 1407-1446 ◽

Cited By ~ 2

Author(s):

A. Werner ◽

C. M. Volk ◽

E. V. Ivanova ◽

T. Wetter ◽

C. Schiller ◽

...

Keyword(s):

High Latitude ◽

Trace Gases ◽

Polar Vortex ◽

The Arctic ◽

Late Winter ◽

Mass Balance Calculation ◽

Air Masses ◽

History Of ◽

Simple Mass

Abstract. In-situ measurements of the long-lived trace gases N2O, CFC-11 (CCl3F), H-1211 (CBrClF2), CH4, O3 and H2O performed in the Arctic winter 2003 on board the high-altitude aircraft M55 Geophysica are presented and used to study transport into the lowermost stratosphere (LMS). Fractions of air in the LMS originating in i) the troposphere, ii) the extra-vortex stratosphere above 400 K and iii) the Arctic vortex above 400 K are determined using a simple mass balance calculation. The analysis exhibits a strong tropospheric influence of 50% or more in the lowest 20 K of the high-latitude LMS. Above this region the LMS is dominated by air masses having descended from above 400 K. Below the Arctic vortex region at potential temperatures above 360 K, air in the LMS is a mixture of extra-vortex stratospheric and vortex air masses. The vortex fraction increases from about 40% at 360 K to 100% at 400 K for equivalent latitudes >70° N. This influence of air masses descending through the bottom of the polar vortex increases over the course of the winter. By the end of winter a significant fraction of 30% vortex air in the LMS is found even at an equivalent latitude of 40° N. Since the chemical and dynamical history of vortex air is distinct from that of mid-latitude stratospheric air masses, this study implies that the composition of the mid- to high-latitude LMS during late winter and spring is significantly influenced by the Arctic vortex.

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Quantification of transport across the boundary of the lower stratospheric vortex during Arctic winter 2002/2003

Atmospheric Chemistry and Physics ◽

10.5194/acp-8-3655-2008 ◽

2008 ◽

Vol 8 (13) ◽

pp. 3655-3670 ◽

Cited By ~ 26

Author(s):

G. Günther ◽

R. Müller ◽

M. von Hobe ◽

F. Stroh ◽

P. Konopka ◽

...

Keyword(s):

Lower Stratosphere ◽

Polar Vortex ◽

Lagrangian Model ◽

The Arctic ◽

Original Position ◽

Small Scale ◽

Strong Mixing ◽

Air Masses ◽

Additional Influence ◽

Secondary Vortices

Abstract. Strong perturbations of the Arctic stratosphere during the winter 2002/2003 by planetary waves led to enhanced stretching and folding of the vortex. On two occasions the vortex in the lower stratosphere split into two secondary vortices that re-merged after some days. As a result of these strong disturbances the role of transport in and out of the vortex was stronger than usual. An advection and mixing simulation with the Chemical Lagrangian Model of the Stratosphere (CLaMS) utilising a suite of inert tracers tagging the original position of the air masses has been carried out. The results show a variety of synoptic and small scale features in the vicinity of the vortex boundary, especially long filaments peeling off the vortex edge and being slowly mixed into the mid latitude environment. The vortex folding events, followed by re-merging of different parts of the vortex led to strong filamentation of the vortex interior. During January, February, and March 2003 flights of the Russian high-altitude aircraft Geophysica were performed in order to probe the vortex, filaments and in one case the merging zone between the secondary vortices. Comparisons between CLaMS results and observations obtained from the Geophysica flights show in general good agreement. Several areas affected by both transport and strong mixing could be identified, allowing explanation of many of the structures observed during the flights. Furthermore, the CLaMS simulations allow for a quantification of the air mass exchange between mid latitudes and the vortex interior. The simulation suggests that after the formation of the vortex was completed, its interior remaind relatively undisturbed. Only during the two re-merging events were substantial amounts of extra-vortex air transported into the polar vortex. When in March the vortex starts weakening additional influence from lower latitudes becomes apparent in the model results. In the lower stratosphere export of vortex air leads only to a fraction of about 5% polar air in mid latitudes by the end of March. An upper limit for the contribution of ozone depleted vortex air on mid-latitude ozone loss is derived, indicating that the maximum final impact of dilution is on the order of 50%.

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Chemical ozone loss and ozone mini-hole event during the Arctic winter 2010/2011 as observed by SCIAMACHY and GOME-2

Atmospheric Chemistry and Physics ◽

10.5194/acp-14-3247-2014 ◽

2014 ◽

Vol 14 (7) ◽

pp. 3247-3276 ◽

Cited By ~ 16

Author(s):

R. Hommel ◽

K.-U. Eichmann ◽

J. Aschmann ◽

K. Bramstedt ◽

M. Weber ◽

...

Keyword(s):

Transport Model ◽

Polar Vortex ◽

The Arctic ◽

Optical Absorption Spectroscopy ◽

Late Winter ◽

Total Column Ozone ◽

Bromine Oxide ◽

Ozone Loss ◽

Catalytic Cycles ◽

Total Column

Abstract. Record breaking loss of ozone (O3) in the Arctic stratosphere has been reported in winter–spring 2010/2011. We examine in detail the composition and transformations occurring in the Arctic polar vortex using total column and vertical profile data products for O3, bromine oxide (BrO), nitrogen dioxide (NO2), chlorine dioxide (OClO), and polar stratospheric clouds (PSC) retrieved from measurements made by SCIAMACHY (Scanning Imaging Absorption SpectroMeter for Atmospheric CHartography) on-board Envisat (Environmental Satellite), as well as total column ozone amount, retrieved from the measurements of GOME-2 (Global Ozone Monitoring Experiment) on MetOp-A (Meteorological Experimental Satellite). Similarly we use the retrieved data from DOAS (Differential Optical Absorption Spectroscopy) measurements made in Ny-Ålesund (78.55° N, 11.55° E). A chemical transport model (CTM) has been used to relate and compare Arctic winter–spring conditions in 2011 with those in the previous year. In late winter–spring 2010/2011 the chemical ozone loss in the polar vortex derived from SCIAMACHY observations confirms findings reported elsewhere. More than 70% of O3 was depleted by halogen catalytic cycles between the 425 and 525 K isentropic surfaces, i.e. in the altitude range ~16–20 km. In contrast, during the same period in the previous winter 2009/2010, a typical warm Arctic winter, only slightly more than 20% depletion occurred below 20 km, while 40% of O3 was removed above the 575 K isentrope (~23 km). This loss above 575 K is explained by the catalytic destruction by NOx descending from the mesosphere. In both Arctic winters 2009/2010 and 2010/2011, calculated O3 losses from the CTM are in good agreement to our observations and other model studies. The mid-winter 2011 conditions, prior to the catalytic cycles being fully effective, are also investigated. Surprisingly, a significant loss of O3 around 60%, previously not discussed in detail, is observed in mid-January 2011 below 500 K (~19 km) and sustained for approximately 1 week. The low O3 region had an exceptionally large spatial extent. The situation was caused by two independently evolving tropopause elevations over the Asian continent. Induced adiabatic cooling of the stratosphere favoured the formation of PSC, increased the amount of active chlorine for a short time, and potentially contributed to higher polar ozone loss later in spring.

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Analysis of Arctic Spring Ozone Anomaly in the Phases of QBO and 11-year Solar Cycle for 1979–2011

10.20944/preprints202104.0057.v1 ◽

2021 ◽

Author(s):

Yousuke Yamashita ◽

Hideharu Akiyoshi ◽

Masaaki Takahashi

Keyword(s):

Solar Cycle ◽

Climate Model ◽

Polar Vortex ◽

Reanalysis Data ◽

Early Spring ◽

The Arctic ◽

Negative Anomaly ◽

Late Winter ◽

Quasi Biennial Oscillation ◽

Biennial Oscillation

Arctic ozone amount in winter to spring shows large year-to-year variation. This study investigates Arctic spring ozone in relation to the phase of quasi-biennial oscillation (QBO)/the 11-year solar cycle, using satellite observations, reanalysis data, and outputs of a chemistry climate model (CCM) during the period of 1979–2011. For this duration, we found that the composite mean of the Northern Hemisphere high-latitude total ozone in the QBO-westerly (QBO-W)/solar minimum (Smin) phase is slightly smaller than those averaged for the QBO-W/Smax and QBO-E/Smax years in March. An analysis of a passive ozone tracer in the CCM simulation indicates that this negative anomaly is primarily caused by transport. The negative anomaly is consistent with a weakening of the residual mean downward motion in the polar lower stratosphere. The contribution of chemical processes estimated using the column amount difference between ozone and the passive ozone tracer is between 10–20% of the total anomaly in March. The lower ozone levels in the Arctic spring during the QBO-W/Smin years are associated with a stronger Arctic polar vortex from late winter to early spring, which is linked to the reduced occurrence of sudden stratospheric warming in the winter during the QBO-W/Smin years.

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Polar processing in a split vortex: early winter Arctic ozone loss in 2012/13

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-15-4973-2015 ◽

2015 ◽

Vol 15 (4) ◽

pp. 4973-5029 ◽

Cited By ~ 3

Author(s):

G. L. Manney ◽

Z. D. Lawrence ◽

M. L. Santee ◽

N. J. Livesey ◽

A. Lambert ◽

...

Keyword(s):

Nitric Acid ◽

Lower Stratosphere ◽

Polar Vortex ◽

The Arctic ◽

Early Winter ◽

Sudden Stratospheric Warming ◽

Ozone Loss ◽

Chlorine Monoxide ◽

Polar Stratospheric Cloud ◽

Vortex Split

Abstract. A sudden stratospheric warming (SSW) in early January 2013 caused the polar vortex to split. After the lower stratospheric vortex split on 8 January, the two offspring vortices – one over Canada and the other over Siberia – remained intact, well-confined, and largely at latitudes that received sunlight until they reunited at the end of January. As the SSW began, temperatures abruptly rose above chlorine activation thresholds throughout the lower stratosphere. The vortex was very disturbed prior to the SSW, and was exposed to much more sunlight than usual in December 2012 and January 2013. Aura Microwave Limb Sounder (MLS) nitric acid (HNO3) data and observations from CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) indicate extensive polar stratospheric cloud (PSC) activity, with evidence of PSCs containing solid nitric acid trihydrate particles during much of December 2012. Consistent with the sunlight exposure and PSC activity, MLS observations show that chlorine monoxide (ClO) became enhanced early in December. Despite the cessation of PSC activity with the onset of the SSW, enhanced vortex ClO persisted until mid-February, indicating lingering chlorine activation. The smaller Canadian offspring vortex had lower temperatures, lower HNO3, lower hydrogen chloride (HCl), and higher ClO in late January than the Siberian vortex. Chlorine deactivation began later in the Canadian than in the Siberian vortex. HNO3 remained depressed within the vortices after temperatures rose above the PSC existence threshold, and passive transport calculations indicate vortex-averaged denitrification of about 4 ppbv; the resulting low HNO3 values persisted until the vortex dissipated in mid-February. Consistent with the strong chlorine activation and exposure to sunlight, MLS measurements show rapid ozone loss commencing in mid-December and continuing through January. Lagrangian transport estimates suggest ~ 0.7–0.8 ppmv (parts per million by volume) vortex-averaged chemical ozone loss by late January near 500 K (~ 21 km), with substantial loss occurring from ~ 450 to 550 K. The surface area of PSCs in December 2012 was larger than that in any other December observed by CALIPSO. As a result of denitrification, HNO3 abundances in 2012/13 were among the lowest in the MLS record for the Arctic. ClO enhancement was much greater in December 2012 through mid-January 2013 than that at the corresponding time in any other Arctic winter observed by MLS. Furthermore, reformation of HCl appeared to play a greater role in chlorine deactivation than in more typical Arctic winters. Ozone loss in December 2012 and January 2013 was larger than any previously observed in those months. This pattern of exceptional early winter polar processing and ozone loss resulted from the unique combination of dynamical conditions associated with the early January 2013 SSW, namely unusually low temperatures in December 2012 and offspring vortices that remained well-confined and largely in sunlit regions for about a month after the vortex split.

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Lagrangian analysis of the northern polar vortex split in April 2020 during development of the Arctic ozone hole

10.5194/egusphere-egu21-13597 ◽

2021 ◽

Author(s):

Jezabel Curbelo ◽

Gang Chen ◽

Carlos R. Mechoso

Keyword(s):

Wave Train ◽

Stratospheric Ozone ◽

Polar Vortex ◽

Early Spring ◽

Ozone Hole ◽

The Arctic ◽

Late Winter ◽

Lagrangian Analysis ◽

The North ◽

Vortex Split

<div>The evolution of the Northern Hemisphere stratosphere during late winter and early spring of 2020 was punctuated by outstanding events both in dynamics and tracer evolution. It provides an ideal case for study of the Lagrangian properties of the evolving flow and its connections with the troposphere. The events ranged from an episode of polar warming at upper levels in March, a polar vortex split into two cyclonic vortices at middle and lower levels in April, and a remarkably deep and persistent mass of ozone poor air within the westerly circulation throughout the period. The latter feature was particularly remarkable during 2020, which showed the lowest values of stratospheric ozone on record.</div><div>&#160;</div><div>We focus on the vortex split in April 2020 and we examine this split at middle as well as lower stratospheric levels, and the interactions that occurred between the resulting two vortices which determined the distribution of ozone among them. We also examine the connections among stratospheric and tropospheric events during the period.</div><div>&#160;</div><div>Our approach for analysis will be based on the application of Lagrangian tools to the flow field, based on following air parcels trajectories, examining barriers to the flow, and the activity and propagation of planetary waves. Our findings confirm the key role for the split played by a flow configuration with a polar hyperbolic trajectory and associated manifolds. A trajectory analysis illustrates the transport of ozone between the vortices during the split. We argue that these stratospheric events were linked to strong synoptic scale disturbances in the troposphere forming a wave train from the north Pacific to North America and Eurasia.</div><div><strong>&#160;</strong></div><div><strong>Reference:</strong><strong> </strong>J. Curbelo, G. Chen,&#160; C. R. Mechoso. Multi-level analysis of the northern polar vortex split in April 2020 during development of the Arctic ozone hole. Earth and Space Science Open Archive. doi: 10.1002/essoar.10505516.1</div><div>&#160;</div><div><strong>Acknowledgements:</strong> NSF Grant AGS-1832842, RYC2018-025169 and EIN2019-103087.</div>

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Chemical analysis of refractory stratospheric aerosol particles collected within the arctic vortex and inside polar stratospheric clouds

10.5194/acp-2016-128 ◽

2016 ◽

Author(s):

Martin Ebert ◽

Ralf Weigel ◽

Konrad Kandler ◽

Gebhard Günther ◽

Sergej Molleker ◽

...

Keyword(s):

Aerosol Particles ◽

Stratospheric Aerosol ◽

The Arctic ◽

Late Winter ◽

General Tendency ◽

Polar Stratospheric Clouds ◽

Metal Mixtures ◽

Air Masses ◽

Size And Morphology ◽

Stratospheric Clouds

Abstract. Stratospheric aerosol particles with diameters larger than about 10 nm were collected within the arctic vortex during two polar flight campaigns: RECONCILE in winter 2010 and ESSenCe in winter 2011. Impactors were installed on board of the aircraft M-55 Geophysica, which was operated from Kiruna, Sweden. Flights were performed in a height of up to 21 km and some of the particle samples were taken within distinct polar stratospheric clouds (PSC). The chemical composition, size and morphology of refractory particles were analyzed by scanning electron microscopy and energy-dispersive X-ray microanalysis. During ESSenCe no refractory particles with diameters above 500 nm were sampled. In total 116 small silicate-, Fe-rich-, Pb-rich and aluminum oxide spheres were found. In contrast to ESSenCe early winter, during the late winter RECONCILE mission the air masses were subsiding inside the Arctic winter vortex from upper stratosphere and mesosphere, thus initializing a transport of refractory aerosol particles into the lower stratosphere. During RECONCILE 759 refractory particles with diameters above 500 nm were found consisting of silicates, silicate/carbon mixtures, Fe-rich particles, Ca-rich particles and complex metal mixtures. In the size range below 500 nm additionally the presence of soot was proven. While the data base is still sparse, the general tendency of a lower abundance of refractory particles during PSC events compared to non-PSC situations was observed. The detection of such large refractory particles in the stratosphere, and the fact that these particles were not observed in the particle samples (upper size limit about 5 µm) taken during PSC events, strengthen the hypothesis that such particles are present in the polar stratosphere in late winter and that they can provide a surface for heterogeneous condensation during PSC formation.

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Anomalous quasi-stationary planetary waves over the Antarctic region in 1988 and 2002

Annales Geophysicae ◽

10.5194/angeo-26-1101-2008 ◽

2008 ◽

Vol 26 (5) ◽

pp. 1101-1108 ◽

Cited By ~ 11

Author(s):

A. V. Grytsai ◽

O. M. Evtushevsky ◽

G. P. Milinevsky

Keyword(s):

Lower Stratosphere ◽

Polar Vortex ◽

Amplitude Distribution ◽

Stationary Wave ◽

Planetary Waves ◽

Late Winter ◽

Stratospheric Polar Vortex ◽

Latitudinal Position ◽

The Antarctic ◽

Peak Value

Abstract. Anomalies in the Antarctic total ozone and amplitudes of the quasi-stationary planetary waves in the lower stratosphere temperature during the winter and spring of 1988 and 2002 have been compared. Westward displacement of the quasi-stationary wave (QSW) extremes by 50°–70° relative to the preceding years of the strong stratospheric polar vortex in 1987 and 2001, respectively, was observed. A dependence of the quasi-stationary wave ridge and trough positions on the strength of the westerly zonal wind in the lower stratosphere is shown. Comparison of the QSW amplitude in the lower stratosphere temperature in July and August shows that the amplitude distribution with latitude in August could be considered as a possible indication of the future anomalous warming in Antarctic spring. In August 2002, the QSW amplitude of 10 K at the edge region of the polar vortex (60° S–65° S) preceded the major warming in September, whereas in August 1988, the highest 7 K amplitude at 55° S preceded the large warming in the next months. These results suggest that the peak value of the lower stratosphere temperature QSW amplitude and the peak latitudinal position in late winter can influence the southern polar vortex strength in spring.

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