Whole Atmosphere Coupling during the September 2019 Antarctic Sudden Stratospheric Warming

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.

Download Full-text

Identification of the mechanisms responsible for anomalies in the tropical lower thermosphere/ionosphere caused by the January 2009 sudden stratospheric warming

Journal of Space Weather and Space Climate ◽

10.1051/swsc/2019037 ◽

2019 ◽

Vol 9 ◽

pp. A39 ◽

Cited By ~ 1

Author(s):

Maxim V. Klimenko ◽

Vladimir V. Klimenko ◽

Fedor S. Bessarab ◽

Timofei V. Sukhodolov ◽

Pavel A. Vasilev ◽

...

Keyword(s):

Electric Field ◽

Phase Change ◽

Lower Thermosphere ◽

Upper Atmosphere ◽

Electron Content ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Low Latitude ◽

Plasma Drift ◽

Solar Tide

We apply the Entire Atmosphere GLobal (EAGLE) model to investigate the upper atmosphere response to the January 2009 sudden stratospheric warming (SSW) event. The model successfully reproduces neutral temperature and total electron content (TEC) observations. Using both model and observational data, we identify a cooling in the tropical lower thermosphere caused by the SSW. This cooling affects the zonal electric field close to the equator, leading to an enhanced vertical plasma drift. We demonstrate that along with a SSW-related wind disturbance, which is the main source to form a dynamo electric field in the ionosphere, perturbations of the ionospheric conductivity also make a significant contribution to the formation of the electric field response to SSW. The post-sunset TEC enhancement and pre-sunrise electron content reduction are revealed as a response to the 2009 SSW. We show that at post-sunset hours the SSW affects low-latitude TEC via a disturbance of the meridional electric field. We also show that the phase change of the semidiurnal migrating solar tide (SW2) in the neutral wind caused by the 2009 SSW at the altitude of the dynamo electric field generation has a crucial importance for the SW2 phase change in the zonal electric field. Such changes lead to the appearance of anomalous diurnal variability of the equatorial electromagnetic plasma drift and subsequent low-latitudinal TEC disturbances in agreement with available observations. Plain Language Summary – Entire Atmosphere GLobal model (EAGLE) interactively calculates the troposphere, stratosphere, mesosphere, thermosphere, and plasmasphere–ionosphere system states and their response to various natural and anthropogenic forcing. In this paper, we study the upper atmosphere response to the major sudden stratospheric warming that occurred in January 2009. Our results agree well with the observed evolution of the neutral temperature in the upper atmosphere and with low-latitude ionospheric disturbances over America. For the first time, we identify an SSW-related cooling in the tropical lower thermosphere that, in turn, could provide additional information for understanding the mechanisms for the generation of electric field disturbances observed at low latitudes. We show that the SSW-related vertical electromagnetic drift due to electric field disturbances is a key mechanism for interpretation of an observed anomalous diurnal development of the equatorial ionization anomaly during the 2009 SSW event. We demonstrate that the link between thermospheric winds and the ionospheric dynamo electric field during the SSW is attained through the modulation of the semidiurnal migrating solar tide.

Download Full-text

Impact of Antarctic Sudden Stratospheric Warming on Mid-Latitude Thermosphere and Ionosphere over USA and Europe

10.5194/egusphere-egu21-10289 ◽

2021 ◽

Author(s):

Larisa Goncharenko ◽

V Lynn Harvey ◽

Katelynn Greer ◽

Shun-Rong Zhang ◽

Anthea Coster

Keyword(s):

The Arctic ◽

Electron Content ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Opposite Hemisphere ◽

Total Electron ◽

Middle Latitudes ◽

Western Us ◽

Declination Angle ◽

Thermospheric Winds

Limited observational evidence indicates that ionospheric changes caused by Arctic SSWs propagate to at least the middle latitudes in the Southern Hemisphere. However, it is not known if similar ionospheric anomalies are produced by Antarctic SSWs, mostly because Antarctic SSWs occur less often than the Arctic events. The sudden stratospheric warming of September 2019 has provided a perfect opportunity to investigate whether SSW are linked to upper atmospheric anomalies at middle latitudes of the opposite hemisphere. In this study we provide an overview of thermospheric and ionospheric anomalies observed in September 2019 at middle latitudes in the Northern Hemisphere. Our results indicate persistent and strong positive anomalies in total electron content and thermospheric O/N2 ratio observed in the western region of USA. Central and eastern regions of USA do not experience similar positive perturbations and show mostly moderate suppression of TEC reaching 20-40% of the baseline. Both positive and negative anomalies are observed over the central Europe. We discuss potential mechanisms that could be responsible for the observed features and suggest that regional differences in TEC response could be related to modulation of thermospheric winds by SSW and large declination angle over Western US.

Download Full-text

Propagation of gravity waves and its effects on pseudomomentum flux in a sudden stratospheric warming event

10.5194/egusphere-egu21-1909 ◽

2021 ◽

Author(s):

In-Sun Song ◽

Changsup Lee ◽

Hye-Yeong Chun ◽

Jeong-Han Kim ◽

Geonhwa Jee ◽

...

Keyword(s):

Ray Tracing ◽

Gravity Waves ◽

Lower Thermosphere ◽

Upper Atmosphere ◽

Lower Atmosphere ◽

Horizontal Wind ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Curvature Effects ◽

Zonal Wavenumber

Effects of realistic propagation of gravity waves (GWs) on distribution of GW pseudomomentum fluxes are explored using a global ray-tracing model for the 2009 sudden stratospheric warming (SSW) event. Four-dimensional (4D;&#160;x&#8211;z&#160;and&#160;t) and two-dimensional (2D;&#160;z&#160;and&#160;t) results are compared for various parameterized pseudomomentum fluxes. In ray-tracing equations, refraction due to horizontal wind shear and curvature effects are found important and comparable to one another in magnitude. In the 4D, westward pseudomomentum fluxes are enhanced in the upper troposphere and northern stratosphere due to refraction and curvature effects around fluctuating jet flows. In the northern polar upper mesosphere and lower thermosphere, eastward pseudomomentum fluxes are increased in the 4D. GWs are found to propagate more to the upper atmosphere in the 4D, since horizontal propagation and change in wave numbers due to refraction and curvature effects can make it more possible that GWs elude critical level filtering and saturation in the lower atmosphere. GW focusing effects occur around jet cores, and ray-tube effects appear where the polar stratospheric jets vary substantially in space and time. Enhancement of the structure of zonal wavenumber 2 in pseudomomentum fluxes in the middle stratosphere begins from the early stage of the SSW evolution. An increase in pseudomomentum fluxes in the upper atmosphere is present even after the onset in the 4D. Significantly enhanced pseudomomentum fluxes, when the polar vortex is disturbed, are related to GWs with small intrinsic group velocity (wave capture), and they would change nonlocally nearby large-scale vortex structures without substantially changing local mean flows.

Download Full-text

Changes in the middle and upper atmosphere parameters during the January 2013 sudden stratospheric warming

Solnechno-Zemnaya Fizika ◽

10.12737/szf-44201807 ◽

2018 ◽

Vol 4 (4) ◽

pp. 62-75

Author(s):

Анна Ясюкевич ◽

Anna Yasyukevich ◽

Максим Клименко ◽

Maksim Klimenko ◽

Юрий Куликов ◽

...

Keyword(s):

Molecular Nitrogen ◽

Stratospheric Ozone ◽

Upper Atmosphere ◽

Electron Content ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Total Electron ◽

Model Calculations ◽

Long Time ◽

Critical Frequency Fof2

We present the results of complex obser-vations of various parameters of the middle and upper atmosphere over Siberia in December 2012 – January 2013, during a major sudden stratospheric warming (SSW) event. We analyze variations in ozone concentration from microwave measurements, in stratosphere and lower mesosphere temperatures from lidar and satellite measurements, in the F2-layer critical frequency (foF2), in the total electron content (TEC), as well as in the ratio of concentrations of atomic oxygen to molecular nitrogen (O/N2) in the thermosphere. To interpret the observed disturbances in the upper atmosphere, the experimental measurements are compared with the results of model calculations obtained with the Global Self-consistent Model of Thermosphere—Ionosphere—Protonosphere (GSM TIP). The response of the upper atmosphere to the SSW event is shown to be a decrease in foF2 and TEC during the evolution of the warming event and a prolonged increase in O/N2, foF2, and TEC after the SSW maximum. For the first time, we observe the relation between the increase in stratospheric ozone, thermospheric O/N2, and ionospheric electron density for a fairly long time (up to 20 days) after the SSW maximum at midlatitudes.

Download Full-text

Changes in the middle and upper atmosphere parameters during the January 2013 sudden stratospheric warming

Solar-Terrestrial Physics ◽

10.12737/stp-44201807 ◽

2018 ◽

Vol 4 (4) ◽

pp. 48-58 ◽

Cited By ~ 4

Author(s):

Анна Ясюкевич ◽

Anna Yasyukevich ◽

Максим Клименко ◽

Maksim Klimenko ◽

Юрий Куликов ◽

...

Keyword(s):

Molecular Nitrogen ◽

Stratospheric Ozone ◽

Upper Atmosphere ◽

Electron Content ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Total Electron ◽

Model Calculations ◽

Long Time ◽

Critical Frequency Fof2

We present the results of complex obser-vations of various parameters of the middle and upper atmosphere over Siberia in December 2012 – January 2013, during a major sudden stratospheric warming (SSW) event. We analyze variations in ozone concentration from microwave measurements, in stratosphere and lower mesosphere temperatures from lidar and satellite measurements, in the F2-layer critical frequency (foF2), in the total electron content (TEC), as well as in the ratio of concentrations of atomic oxygen to molecular nitrogen (O/N2) in the thermosphere. To interpret the observed disturbances in the upper atmosphere, the experimental measurements are compared with the results of model calculations obtained with the Global Self-consistent Model of Thermosphere—Ionosphere—Protonosphere (GSM TIP). The response of the upper atmosphere to the SSW event is shown to be a decrease in foF2 and TEC during the evolution of the warming event and a prolonged increase in O/N2, foF2, and TEC after the SSW maximum. For the first time, we observe the relation between the increase in stratospheric ozone, thermospheric O/N2, and ionospheric electron density for a fairly long time (up to 20 days) after the SSW maximum at midlatitudes.

Download Full-text

Hemispheric asymmetry of the ionospheric variation during major sudden stratospheric warming events

10.5194/egusphere-egu2020-20247 ◽

2020 ◽

Author(s):

Donghe Zhang ◽

Jing Liu

Keyword(s):

Hemispheric Asymmetry ◽

Relative Strength ◽

Magnetic Equator ◽

Electron Content ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Total Electron ◽

The North ◽

Latitudinal Variations ◽

The Difference

The hemispheric asymmetry of the ionospheric variation in the American sector (45&#176;N~45&#176;S, MLAT; 80&#176;~60&#176;W) is studied with total electron content (TEC) data during major sudden stratospheric warming events. The amplitude (AM2) and relative strength (RSM2) of the semi-diurnal lunar tidal component (M2) of TEC are analyzed. RSM2 is the ratio between the energy of M2 and the energy of all the studied tidal components. The magnitudes of AM2 and RSM2 exhibit clear hemispheric and latitudinal variations. The AM2 in the north of the magnetic equator tends to occur at lower magnetic latitudes than the AM2 in the south of the magnetic equator. The RSM2 exhibits similar features as the AM2 but the difference is more distinct. We suggest that such hemispheric asymmetry of M2 parameters is related to the hemispheric asymmetry of the EIA and the latitudinal variation of the amplitude of the solar tidal components in winter.

Download Full-text

Influence of January 2009 stratospheric warming on HF radio wave propagation in the low-latitude ionosphere

Solnechno-Zemnaya Fizika ◽

10.12737/21880 ◽

2016 ◽

Vol 2 (4) ◽

pp. 63-75

Author(s):

Дарья Котова ◽

Daria Kotova ◽

Максим Клименко ◽

Maksim Klimenko ◽

Владимир Клименко ◽

...

Keyword(s):

Wave Propagation ◽

Radio Wave ◽

Environmental Changes ◽

Equatorial Ionosphere ◽

Radio Wave Propagation ◽

Electron Content ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Total Electron ◽

Low Latitude Ionosphere

For the first time, we consider the effect of the January 23–27, 2009 sudden stratospheric warming (SSW) event on HF radio wave propagation in the equatorial ionosphere. This event took place during extremely low solar and geomagnetic activity. We use the simulation results obtained with the Global Self-consistent Model of the Thermosphere, Ionosphere and Protonosphere (GSM TIP) for simulating environmental changes during the SSW event. We both qualitatively and quantitatively reproduce total electron content disturbances obtained from global ground network receiver observations of GPS navigation satellite signals, by setting an additional electric potential and TIME-GCM model output at a height of 80 km. In order to study the influence of this SSW event on HF radio wave propagation and attenuation, we use the numerical model of radio wave propagation based on geometrical optics approximation. It is shown that a sudden stratospheric warming leads to radio signal attenuation in the day-time equatorial ionosphere.

Download Full-text

Nonmigrating tidal activity related to the sudden stratospheric warming in the Arctic winter of 2003/2004

Annales Geophysicae ◽

10.5194/angeo-27-975-2009 ◽

2009 ◽

Vol 27 (3) ◽

pp. 975-987 ◽

Cited By ~ 24

Author(s):

D. Pancheva ◽

P. Mukhtarov ◽

B. Andonov

Keyword(s):

Middle Atmosphere ◽

Detailed Comparison ◽

The Arctic ◽

Stratospheric Warming ◽

Sudden Stratospheric Warming ◽

Double Peak ◽

Zonal Wavenumber ◽

Nonmigrating Tides ◽

Tide Interaction ◽

Diurnal Tides

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

Quasi-10 d wave modulation of an equatorial ionization anomaly during the Southern Hemisphere stratospheric warming of 2002

Annales Geophysicae ◽

10.5194/angeo-38-9-2020 ◽

2020 ◽

Vol 38 (1) ◽

pp. 9-16 ◽

Cited By ~ 2

Author(s):

Xiaohua Mo ◽

Donghe Zhang

Keyword(s):

Southern Hemisphere ◽

Planetary Wave ◽

Lower Thermosphere ◽

Periodic Oscillation ◽

Electron Content ◽

Stratospheric Warming ◽

Total Electron ◽

Equatorial Ionization Anomaly ◽

E Region ◽

D Wave

Abstract. The present paper studies the perturbations in an equatorial ionization anomaly (EIA) region during the Southern Hemisphere (SH) sudden stratospheric warming (SSW) of 2002, using the location of EIA crests derived from global positioning system (GPS) station observations, the total electron content (TEC) obtained by the International GNSS (global navigation satellite system) Service (IGS) global ionospheric TEC map (GIMs) and the equatorial electrojet (EEJ) estimated by the geomagnetic field in the Asian sector. The results indicate the existence of an obvious quasi-10 d periodic oscillation in the location and TEC of the northern and southern EIA crest. An eastward phase progression of the quasi-10 d wave producing the SH SSW of 2002 is also identified in polar stratospheric temperature. Previous studies have shown that a strong quasi-10 d planetary wave with zonal wave numbers s=1 extended from the lower stratosphere to the mesosphere and lower thermosphere during the SH SSW of 2002 (Palo et al., 2005). Moreover, the EEJ driven by the equatorial zonal electric field exhibits quasi-10 d oscillation, suggesting the enhanced quasi-10 d planetary wave associated with SSW penetrates into the ionosphere E region and produces oscillation in the EIA region through modulating the E-region electric fields. Our results reveal some newer features of ionospheric variation that have not been reported during Northern Hemisphere (NH) SSWs.

Download Full-text