Observations of Reduced Turbulence and Wave Activity in the Arctic Middle Atmosphere Following the January 2015 Sudden Stratospheric Warming

Abstract. This paper is focused on the nonmigrating tidal activity seen in the SABER/TIMED temperatures that is related to the major sudden stratospheric warming (SSW) taking place in the Arctic winter of 2003/2004. The emphasis is on the nonmigrating diurnal tides observed in the stratosphere and lower mesosphere which is usually accepted to be insignificant in comparison with that in the upper mesosphere and thermosphere. By using different independent spectral methods we found a significant amplification in December–January of the following nonmigrating 24-h tides: zonally symmetric (s=0), eastward propagating with zonal wavenumber 1 (E1), and westward propagating with zonal wavenumbers 2 and 3 (W2 and W3) tides. It has been found that the double peak nonmigrating tidal amplifications located in the stratosphere (~40 km) and in the lower mesosphere (~70 km) are a consequence of the maintained hydrostatic relation. By detailed comparison of the evolution and spatial structure of the nonmigrating diurnal tides with those of the migrating diurnal tide and stationary planetary waves (SPWs) evidence for a SPW-migrating tide interaction as a source of nonmigrating tides has been presented. Therefore, the nonmigrating 24-h tides turn out to be an important component of the middle atmosphere dynamics during the major SSW in the Arctic winter of 2003/2004.

Download Full-text

Vertical Atmospheric Coupling during the September 2019 Antarctic Sudden Stratospheric Warming

10.5194/egusphere-egu2020-11224 ◽

2020 ◽

Author(s):

Yosuke Yamazaki ◽

Vivien Matthias ◽

Yasunobu Miyoshi ◽

Claudia Stolle ◽

Tarique Siddiqui ◽

...

Keyword(s):

Large Scale ◽

Middle Atmosphere ◽

Lower Thermosphere ◽

Upper Atmosphere ◽

The Arctic ◽

Electron Content ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Total Electron ◽

Zonal Wavenumber

<p>A sudden stratospheric warming (SSW) is an extreme wintertime meteorological phenomenon occurring mostly over the Arctic region. Studies have shown that an Arctic SSW can influence the whole atmosphere including the ionosphere. In September 2019, a rare SSW event occurred in the Antarctic region, following strong wave-1 planetary wave activity. The event provides an opportunity to investigate its broader impact on the upper atmosphere, which has been largely unexplored in previous studies. Ionospheric data from ESA's Swarm satellite constellation mission show prominent 6-day variations in the dayside low-latitude region during the SSW, including 20-70% variations in the equatorial zonal electric field, 20-40% variations in the electron density, and 5-10% variations in the top-side total electron content. These ionospheric variations have characteristics of a westward-propagating wave with zonal wavenumber 1, and can be attributed to forcing from the middle atmosphere by the Rossby normal mode &#8220;quasi-6-day wave&#8221; (Q6DW). Geopotential height measurements by the Microwave Limb Sounder aboard NASA's Aura satellite reveal a burst of global Q6DW activity in the mesosphere and lower thermosphere at this time, which is one of the strongest in the record. These results suggest that an Antarctic SSW can lead to ionospheric variability by altering middle atmosphere dynamics and propagation characteristics of large-scale waves from the middle atmosphere to the upper atmosphere.</p>

Download Full-text

Analysis of the Arctic polar vortex dynamics during the sudden stratospheric warming in January 2009

Arctic and Antarctic Research ◽

10.30758/0555-2648-2021-67-2-134-146 ◽

2021 ◽

Vol 67 (2) ◽

pp. 134-146

Author(s):

V. V. Zuev ◽

E. S. Savelieva ◽

A. V. Pavlinsky

Keyword(s):

Wind Speed ◽

Polar Vortex ◽

Reanalysis Data ◽

Wave Activity ◽

The Arctic ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Mean Wind Speed ◽

The Mean ◽

Middle Stratosphere

The Arctic polar vortex is often affected by wave activity during its life cycle. The planetary Rossby waves propagating from the troposphere to the stratosphere occasionally lead to the displacement or splitting of the polar vortex, accompanied by sudden stratospheric warming (SSW). In January 2009, one of the largest SSWs was observed in the Arctic. In this work, the dynamics of the polar vortex during the 2009 SSW is considered using a new method that allows one to estimate the vortex area, the wind speed at the vortex edge, the mean temperature and ozone mass mixing ratio inside the vortex, based on the fact that the Arctic vortex edge at the 50 and 10 hPa pressure levels is determined by the geopotential values, respectively, 19.5. 104 and 29.5. 104 m2 /s2 , using the ERA5 reanalysis data. The application of this method is justified for the Arctic polar vortex, which is characterized by significant variability, especially during the period of its splitting. The splitting of the polar vortex in 2009 was observed on January 24 and 28, respectively, in the middle and lower stratosphere. About a week after the splitting, the vortices became closer in characteristics to small cyclones, which completely collapsed within 1–3 weeks. The influence of planetary wave activity on the polar vortex does not always lead to its breakdown. Short-term splitting of the polar vortex is sometimes observed for several days after which the polar vortex strengthens again and PSCs form inside the vortex. Such a recovery of the polar vortex is most likely to occur in the winter. Based on the analysis of the dynamics of the Arctic polar vortex for 1979–2020 and using the example of the 2009 SSW, we showed that when the vortex area decreases to less than 10 million km2 and the mean wind speed at the vortex edge decreases below 30 and 45 m/s, respectively, in the lower and middle stratosphere, the polar vortex becomes a small cyclone (with significantly higher temperatures within it), which usually collapses within 3 weeks.

Download Full-text

Small-scale variability of stratospheric ozone during the sudden stratospheric warming 2018/2019 observed at Ny-Ålesund, Svalbard

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-10791-2020 ◽

2020 ◽

Vol 20 (18) ◽

pp. 10791-10806 ◽

Cited By ~ 1

Author(s):

Franziska Schranz ◽

Jonas Hagen ◽

Gunter Stober ◽

Klemens Hocke ◽

Axel Murk ◽

...

Keyword(s):

Water Vapour ◽

Planetary Wave ◽

Stratospheric Ozone ◽

Elevation Angle ◽

Wave Activity ◽

The Arctic ◽

Small Scale ◽

Horizontal Distance ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming

Abstract. Middle atmospheric ozone, water vapour and zonal and meridional wind profiles have been measured with the two ground-based microwave radiometers GROMOS-C and MIAWARA-C. The instruments have been located at the Arctic research base AWIPEV at Ny-Ålesund, Svalbard (79∘ N, 12∘ E), since September 2015. GROMOS-C measures ozone spectra in the four cardinal directions with an elevation angle of 22∘. This means that the probed air masses at an altitude of 3 hPa (37 km) have a horizontal distance of 92 km to Ny-Ålesund. We retrieve four separate ozone profiles along the lines of sight and calculate daily mean horizontal ozone gradients which allow us to investigate the small-scale spatial variability of ozone above Ny-Ålesund. We present the evolution of the ozone gradients at Ny-Ålesund during winter 2018/2019, when a major sudden stratospheric warming (SSW) took place with the central date at 2 January, and link it to the planetary wave activity. We further analyse the SSW and discuss our ozone and water vapour measurements in a global context. At 3 hPa we find a distinct seasonal variation of the ozone gradients. The strong polar vortex during October and March results in a decreasing ozone volume mixing ratio towards the pole. In November the amplitudes of the planetary waves grow until they break in the end of December and an SSW takes place. From November until February ozone increases towards higher latitudes and the magnitude of the ozone gradients is smaller than in October and March. We attribute this to the planetary wave activity of wave numbers 1 and 2 which enabled meridional transport. The MERRA-2 reanalysis and the SD-WACCM model are able to capture the small-scale ozone variability and its seasonal changes.

Download Full-text

Tropospheric forcing of the boreal polar vortex splitting in January 2003

Annales Geophysicae ◽

10.5194/angeo-28-2133-2010 ◽

2010 ◽

Vol 28 (11) ◽

pp. 2133-2148 ◽

Cited By ~ 9

Author(s):

D. H. W. Peters ◽

P. Vargin ◽

A. Gabriel ◽

N. Tsvetkova ◽

V. Yushkov

Keyword(s):

Rossby Wave ◽

Planetary Wave ◽

Winter Season ◽

Polar Vortex ◽

Wave Activity ◽

The Arctic ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Stratospheric Polar Vortex ◽

Wave Trains

Abstract. The dynamical evolution of the relatively warm stratospheric winter season 2002–2003 in the Northern Hemisphere was studied and compared with the cold winter 2004–2005 based on NCEP-Reanalyses. Record low temperatures were observed in the lower and middle stratosphere over the Arctic region only at the beginning of the 2002–2003 winter. Six sudden stratospheric warming events, including the major warming event with a splitting of the polar vortex in mid-January 2003, have been identified. This led to a very high vacillation of the zonal mean circulation and a weakening of the stratospheric polar vortex over the whole winter season. An estimate of the mean chemical ozone destruction inside the polar vortex showed a total ozone loss of about 45 DU in winter 2002–2003; that is about 2.5 times smaller than in winter 2004–2005. Embedded in a winter with high wave activity, we found two subtropical Rossby wave trains in the troposphere before the major sudden stratospheric warming event in January 2003. These Rossby waves propagated north-eastwards and maintained two upper tropospheric anticyclones. At the same time, the amplification of an upward propagating planetary wave 2 in the upper troposphere and lower stratosphere was observed, which could be caused primarily by those two wave trains. Furthermore, two extratropical Rossby wave trains over the North Pacific Ocean and North America were identified a couple of days later, which contribute mainly to the vertical planetary wave activity flux just before and during the major warming event. It is shown that these different tropospheric forcing processes caused the major warming event and contributed to the splitting of the polar vortex.

Download Full-text

Winter 2018 major sudden stratospheric warming impact on midlatitude mesosphere from microwave radiometer measurements

10.5194/acp-2018-1361 ◽

2019 ◽

Cited By ~ 2

Author(s):

Yuke Wang ◽

Valery Shulga ◽

Gennadi Milinevsky ◽

Aleksey Patoka ◽

Oleksandr Evtushevsky ◽

...

Keyword(s):

Zonal Wind ◽

Geopotential Height ◽

Microwave Radiometer ◽

Recovery Phase ◽

The Arctic ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Easterly Wind ◽

The Impact ◽

Midlatitude Mesosphere

Abstract. The impact of a major sudden stratospheric warming (SSW) in the Arctic in February 2018 on the mid-latitude mesosphere was investigated by performing microwave radiometer measurements of carbon monoxide (CO) and zonal wind above Kharkiv, Ukraine (50.0° N, 36.3° E). The mesospheric peculiarities of this SSW event were observed using recently designed and installed microwave radiometer in East Europe for the first time. The data from the ERA-Interim and NCEP–NCAR reanalyses, as well as the Aura Microwave Limb Sounder measurements, have been also used. Microwave observations of the daily CO profiles in January–March 2018 allowed retrieving mesospheric zonal wind at 70–85 km (below the winter mesopause) over the Kharkiv site. The reverse of the mesospheric westerly from about 10 m s−1 to the easterly wind of about −10 m s−1 around 10 February has been registered. Local microwave observations in the NH midlatitudes combined with reanalysis data show wide ranges of daily variability in CO, zonal wind, temperature and geopotential height in the mesosphere and stratosphere during the SSW 2018. Oscillations in the vertical CO profile, zonal wind, and geopotential height during the SSW, stratopause disappearance after the SSW onset and strong CO and westerly wind peaks at the start of the SSW recovery phase have been observed. The observed CO variability can be explained by vertical and horizontal air mass redistribution due to planetary wave activity with the replacement of the CO-rich air by CO-poor air and vice versa, in agreement with other studies. The results of microwave measurements of CO and zonal wind in the midlatitude mesosphere at 70–85 km altitudes, which still is not adequately covered by ground-based observations, are useful for improving our understanding of the SSW impacts in this region.

Download Full-text

Stratosphere-troposphere Dynamical Coupling over Boreal Extratropics during the Sudden Stratospheric Warming in the Arctic in January–February 2017

Russian Meteorology and Hydrology ◽

10.3103/s1068373918050011 ◽

2018 ◽

Vol 43 (5) ◽

pp. 277-287 ◽

Cited By ~ 2

Author(s):

P. N. Vargin

Keyword(s):

The Arctic ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Dynamical Coupling

Download Full-text

Analyzing ozone variations and uncertainties at high latitudes during Sudden Stratospheric Warming events using MERRA-2

10.5194/acp-2021-646 ◽

2021 ◽

Author(s):

Shima Bahramvash Shams ◽

Von P. Walden ◽

James W. Hannigan ◽

William J. Randel ◽

Irina V. Petropavlovskikh ◽

...

Keyword(s):

Stratospheric Ozone ◽

Polar Vortex ◽

The Arctic ◽

High Latitudes ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Total Column Ozone ◽

Northern Latitudes ◽

Stratospheric Dynamics ◽

Zonal Average

Abstract. Stratospheric circulation is a critical part of the Arctic ozone cycle. Sudden stratospheric warming events (SSWs) manifest the strongest alteration of stratospheric dynamics. Changes in planetary wave propagation vigorously influence zonal mean zonal wind, temperature, and tracer concentrations in the stratosphere over the high latitudes. In this study, we examine six major SSWs from 2004 to 2020 using the Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2). Using the unique density of observations around the Greenland sector at high latitudes, we perform comprehensive comparisons of high latitude observations with the MERRA-2 ozone dataset during the six major SSWs. Our results show that MERRA-2 captures the high variability of mid stratospheric ozone fluctuations during SSWs over high latitudes. However, larger uncertainties are observed in the lower stratosphere and troposphere. The zonally averaged stratospheric ozone shows a dramatic increase of 9–29 % in total column ozone (TCO) near the time of each SSW, which lasts up to two months. The SSWs exhibit a more significant impact on ozone over high northern latitudes when the polar vortex is mostly elongated as seen in 2009 and 2018 compared to the events in which the polar vortex is displaced towards Europe. The regional impact of SSWs over Greenland has a similar structure as the zonal average, however, exhibits more intense ozone anomalies which is reflected by 15–37 % increase in TCO. The influence of SSW on mid stratospheric ozone levels persists longer than their impact on temperature. This paper is focused on the increased (suppressed) wave activity before (after) the SSWs and their impact on ozone variability at high latitudes. This includes an investigation of the different terms of tracer continuity using MERRA-2 parameters, which emphasizes the key role of vertical advection on mid-stratospheric ozone during the SSWs.

Download Full-text

The Role of Zonal Asymmetry in the Enhancement and Suppression of Sudden Stratospheric Warming Variability by the Madden–Julian Oscillation

Journal of Climate ◽

10.1175/jcli-d-17-0489.1 ◽

2018 ◽

Vol 31 (6) ◽

pp. 2399-2415 ◽

Cited By ~ 4

Author(s):

Wanying Kang ◽

Eli Tziperman

Keyword(s):

General Circulation ◽

Dominant Role ◽

The Arctic ◽

Stationary Waves ◽

Madden Julian Oscillation ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Zonal Asymmetry ◽

Forced Waves ◽

The Arctic Oscillation

Sudden stratospheric warming (SSW) events influence the Arctic Oscillation and midlatitude extreme weather. Previous work showed the Arctic stratosphere to be influenced by the Madden–Julian oscillation (MJO) and that the SSW frequency increases with an increase of the MJO amplitude, expected in a warmer climate. It is shown here that the zonal asymmetry in both the background state and forcing plays a dominant role, leading to either enhancement or suppression of SSW events by MJO-like forcing. When applying a circumglobal MJO-like forcing in a dry dynamic core model, the MJO-forced waves can change the general circulation in three ways that affect the total vertical Eliassen–Palm flux in the Arctic stratosphere. First, weakening the zonal asymmetry of the tropospheric midlatitude jet, and therefore preventing the MJO-forced waves from propagating past the jet. Second, weakening the jet amplitude, reducing the waves generated in the midlatitudes, especially stationary waves, and therefore the upward-propagating planetary waves. Third, reducing the Arctic lower-stratospheric refractory index, which prevents waves from upward propagation. These effects stabilize the Arctic vortex and lower the SSW frequency. The longitudinal range to which the MJO-like forcing is limited plays an important role as well, and the strongest SSW frequency increase is seen when the MJO is located where it is observed in current climate. The SSW suppression effects are active when the MJO-like forcing is placed at different longitudinal locations. This study suggests that future trends in both the MJO amplitude and its longitudinal extent are important for predicting the Arctic stratosphere response.

Download Full-text