Vernadsky Station Research Articles

Investigation of anomalous lightning activity during the January 15, 2022 Tonga volcano eruption based on measurements of the VLF and ELF electromagnetic fields

An anomalous increase in the level of Very Low Frequency (VLF, 3–30 kHz) and Extremely Low Frequency (ELF, 3–3000 Hz) radio noise and the rate of VLF atmospherics was registered during the explosive eruption of the Tonga volcano on January 15, 2022 at the Akademik Vernadsky station (65.246°S; 64.257°W) about 8870 km from the volcano. At the peak activity around 5 UT, the number of atmospherics in 2-min intervals increased by almost 15 times compared to the period preceding the eruption. At this point, the estimated rate reached 360 VLF atmospherics per second. At the same time, an increase in the power spectral density of the magnetic field by 5–9 times was observed in both the ELF and VLF ranges. After 40 min, only on ELF an increased peak lasting ∼10 min was observed, comparable in magnitude to the main peak. According to the Worldwide Lightning Location Network (WWLLN), increased thunderstorm activity was concentrated very close to the volcano during this period. This discrepancy between the intensities of ELF and VLF radiation suggests a significant difference in the parameters of currents in lightning discharges occurring in the area of the volcano vent and in the area of the volcanic ash plume.

Salutogenic outcomes and their personality predictors in participants of year-long Antarctic expeditions

Prolonged stays in extreme living and working conditions at Antarctic stations can result in both negative psychological manifestations and possible positive, salutogenic effects. The aim of this study was to check an assumption about existing salutogenic outcomes and their personality predictors in expeditioners who participated in year-long expeditions. We examined 62 expeditioners who participated in expeditions to the Ukrainian Antarctic Akademik Vernadsky station between 1996 and 2021, including 59 men and three women aged 27 to 68 years. We used the Posttraumatic Growth Inventory—Expanded, the General Self-Efficacy Scale, the Eysenck Personality Questionnaire, the Sixteen Personality Factor Questionnaire and the Professional Hardiness Questionnaire. The majority of expeditioners (55–71%, on various grounds) recorded personal growth following Antarctic deployment, at a level from moderate to high. Based on personality characteristics diagnosed in the abovementioned questionnaires, we created an informative prognostic model explaining 30–45% of the variation in several indicators of expeditioners’ post-expedition growth. The most important predictors of expeditioners’ post-expedition growth were indicators of professional hardiness. Our findings provide additional opportunities to improve psychological evaluation and training for Antarctic expedition personnel.

Snow cover at the Akademik Vernadsky station: response on wind, temperature and precipitation variations

Snow cover at the Akademik Vernadsky station: response on wind, temperature and precipitation variations

Ionospheric response to the February 27, 2023 intense geomagnetic storm over Kharkiv and the Akademik Vernadsky station

Ionospheric response to the February 27, 2023 intense geomagnetic storm over Kharkiv and the Akademik Vernadsky station

Monitoring the technical condition of the fuel storage facility at the Ukrainian Antarctic Akademik Vernadsky station

Monitoring the technical condition of the fuel storage facility at the Ukrainian Antarctic Akademik Vernadsky station

On the performance of CARISMA-Akademik Vernadsky station Schumann resonance monitoring

On the performance of CARISMA-Akademik Vernadsky station Schumann resonance monitoring

On the performance of CARISMA – Akademik Vernadsky station Schumann resonance monitoring

On the performance of CARISMA – Akademik Vernadsky station Schumann resonance monitoring

Estimation of tendencies, homogeneity and stationarity of air temperature at the Ukrainian Antarctic Akademik Vernadsky station during 1951—2020

In this paper results of the complex analysis of surface air temperature tendencies investigations at the Ukrainian Antarctic Akademik Vernadsky station are represented. Antarctica is a region that has a high rate of surface air temperature increase. The Antarctic Peninsula has experienced particularly fast warming, which has the highest temperature rise in the Southern Hemisphere. Therefore, in Antarctica, the study of surface air temperature change is important.
 The Ukrainian Antarctic Akademik Vernadsky station is located on Galindez Island near the Antarctic Peninsula. Investigation of the surface air temperature is especially relevant to the Akademik Vernadsky station, because it has difficult conditions for its formation. The research goal is the estimation of tendencies, homogeneity and stationarity of the annual and mean monthly values of surface air temperature at the Ukrainian Antarctic Akademik Vernadsky station based on a combined approach with the use of several statistical and graphical methods. The use of various statistical methods that differ in characteristics (sensitivity to the law of distribution, autocorrelation, etc.) allows obtaining more reliable estimates. Graphic methods give an opportunity to analyze the tendencies over time and its change periods, the cyclical fluctuations and their characteristics (phases of increase and decrease, their duration, synchronicity, in-phase). Therefore, 4 statistical tests (standard normal Alexandersson test, Buishand test, Pettitt test, von Neumann relation) and 2 graphical methods (mass curve and residual mass curve) were used in the study.
 At the Ukrainian Antarctic Akademik Vernadsky station, the observation series of the mean annual air temperature are quasi-homogeneous and quasi-stationary, as it has only a cooling phase and a warming phase of long-term cyclical fluctuations, which are also unfinished. The transition from the cooling phase to the warming phase took place in 1982. Tendencies in mean monthly air temperatures are similar to tendencies in mean annual temperatures. The differences are only for some months, namely, for the period from September to December.

AIRFLOW SIMULATION AT THE UKRAINIAN ANTARCTIC STATION

The location of the Ukrainian Antarctic Akademik Vernadsky station leads to several problems related to the need to ensure the livelihood and safety of people. The infrastructure of Vernadsky station is affected by significant climatic loads during the year, such as wind, rain, snow and low temperatures. The destruction or even significant damage to the infrastructure of the Antarctic station can endanger the lives of people who are on it due to the inability to evacuate. The purpose of the study is to determine the fields of wind load distribution within the Antarctic Vernadsky station. This is necessary in order to identify the infrastructure objects that are most affected by wind loads. SolidWorks computer-aided design software environment allows you to build geometric models of objects of varying complexity. That is why this system was chosen to model the infrastructure of the Ukrainian Antarctic Vernadsky station. Simulation modeling of wind load was performed in the computer-aided engineering software of finite element analysis ANSYS. Geometric models of the infrastructure objects of the Ukrainian Antarctic Vernadsky station were created. Simulation modeling of the station under wind load conditions was performed. It is shown that in the case of wind from the mainland, the elements of the station's infrastructure that receive the main wind load are the main building and the VST-200. It is determined that the presence of a pile foundation affects the velocity vector fields, so this element should not be neglected when performing further research. It is shown that practically all objects of the station's infrastructure lead to significant turbulent vortices. Geometric models of the infrastructure objects of the Ukrainian Antarctic station Academician Vernadsky were created. Simulation modeling of the station under wind load conditions was performed. It is shown that in the case of wind from the mainland, the elements of the station's infrastructure that receive the main wind load are the main building and the RVS-200. It is determined that the presence of a pile foundation affects the velocity vector fields, so this element should not be neglected when performing further research. It is shown that almost all infrastructure objects of the station lead to significant turbulent tails when they flow around.

Changes in extreme temperature indices at the Ukrainian Antarctic Akademik Vernadsky station, 1951-2020

Changes in extreme temperature indices at the Ukrainian Antarctic Akademik Vernadsky station, 1951-2020

Changes in expeditioners' personality measures during 1 year Antarctic expeditions

AbstractThe extreme working and living conditions at Antarctic stations cause numerous psychological changes in expeditioners. However, research on the changes in expeditioners' personality traits is virtually non-existent. Therefore, the present study aims to determine the changes in expeditioners' personality measures during 1 year Antarctic expeditions. This study examined 56 expeditioners working at the Ukrainian Antarctic Akademik Vernadsky station (52 men, 4 women; ages 20–63 years, M = 38.12, SD = 10.01) who participated in five annual expeditions between 2016 and 2021. The Ukrainian adaptations of four measures were used: the Thomas-Kilmann Conflict Mode Instrument, the Eysenck Personality Questionnaire, the Leonhard-Schmieschek Questionnaire and the Leary Interpersonal Checklist. During 1 year Antarctic expeditions, 8 of the 26 indicators used to describe expeditioners' personality measures changed significantly (P < 0.001–0.1). These indicators belonged to three of the four measures used in the study and were assessed as personally unfavourable. They included increased psychoticism and competing, managerial-autocratic, aggressive-sadistic, responsible-hypernormal, competitive-narcissistic and self-effacing-masochistic styles and a decreased accommodating style. Based on these results, promising areas for further research that could improve psychological selection, training and work for Antarctic expedition personnel are outlined.

Observation of the ionosphere by ionosondes in the Southern and Northern hemispheres during geospace events in October 2021

The paper presents the results of ionospheric observations performed over the Ukrainian Antarctic Akademik Vernadsky station and Millstone Hill (USA). Ionospheric parameters such as peak electron density and height (hmF2 and NmF2) in October 2021 are shown and discussed. The results of the comparative analysis between observations and predictions of the International Reference Ionosphere 2016 (IRI-2016) model are presented. The main objectives of this work are an investigation of the ionosphere response to space weather effects in the Northern and Southern hemispheres in the American longitudinal sectorusing ionosondes located at the Vernadsky station and near the magnetically conjugate region – Millstone Hill, and a comparison of observations with the model. The F2-layer peak height was calculated from ionograms obtained by ionosonde using subsequent electron density profile inversion. Diurnal variations of hmF2 and NmF2 were calculated using a set of sub-models of the IRI-2016 model for comparison with experimental results. A strong negative response of the ionosphere to the moderate geomagnetic storm on October 12, 2021 was revealed over the Vernadsky station and Millstone Hill. During October 21–31, 2021, the gradual night-to-night increase in NmF2 (by a factor of ~2) was observed over the Vernadsky station. It was found that the IRI hmF2 sub-models (SHU-2015 and AMTB-2013) provide a relatively good agreement with the observed variations of hmF2 in the daytime and nighttime for almost the entire investigated period over both the Vernadsky station and Millstone Hill. The largest deviations for both IRI hmF2 sub-models occurred during the nighttime of geomagnetically disturbed periods. The IRI NmF2 submodels (URSI and CCIR) generally agree with the observations. However, observations and model predictions differ somewhat in the geomagnetically disturbed periods. According to the results of the standard deviation calculations, it cannot be concluded that any of the IRI-2016 sub-models is better than the others. The hypotheses on the possible reasons for the differences in the modeled and observed variations of hmF2 and NmF2 are proposed and discussed in the frame of well-known ionospheric storms’ mechanisms. The results obtained in this paper demonstrate the peculiarities of the ionosphere in different hemispheres of the American longitude sector under geomagnetically quiet and disturbed conditions and provide one more validation of the modern empirical international reference models of the ionosphere.

Measured and modeled vertical structure of precipitation during mixed-phase event near the West Coast of the Antarctic Peninsula

Precipitation structures are easy to detect, however, the mesoscale atmospheric processes which they reflect are challenging to understand in Polar Regions and hard to model numerically. Currently, the spatial distribution of precipitation can be tracked at the resolution of minutes and seconds. For this purpose, the researchers at the Ukrainian Antarctic Akademik Vernadsky station employ several near-ground measurement systems and the Micro Rain Radar for remote vertical measurements. Measurements show stochastic precipitation variability caused by turbulence, precipitation bands related to the atmospheric processes of its formation, phase transition (melting) zones, and wind shears. The time scale of bands in the stratiform precipitation typically varied in the range of 5—15 minutes and corresponded to the 2—15 km spatial scale of atmospheric circulations according to the modeled parameters of the atmosphere. The Polar Weather Research and Forecast (Polar WRF) model was used to reveal the general atmospheric conditions. We also tested and evaluated its ability to reproduce small structures. A simple method based on typical model variables is proposed to identify the precipitation melting layer in the simulation data, similar to that determined by radars. The results were satisfyingly consistent with the position of the 0 °C isotherm in the model and with the radar measurements. In addition, the method highlighted supercooled mixed-phase precipitation. Modeling showed good results for large-scale processes like atmospheric fronts and general air mass features in the case study. However, even at the 1 km resolution the simulation reproduced thin mesoscale precipitation features smoothly, which sometimes looks unrealistic. As for other precipitation peculiarities, like band inclination, melting layer position, and mixed-phase zones, the Polar WRF model demonstrates high consistency with observations. The model can describe the atmospheric conditions except for the investigation of precipitation-initiating mechanisms, which still is a challenge for modeling at a small scale.

Results of long-term tectonomagnetic research in the Akademik Vernadsky station region, the West Coast of the Antarctic Peninsula

The study aims to analyze the results of long-term tectonomagnetic observations on the Antarctic tectonomagnetic polygon in the region of the Akademik Vernadsky station to investigate the current geodynamics at the West Coast of the Antarctic Peninsula. The data (1998—2020) were collected as regular discrete geomagnetic measurements. They were used to study the temporal changes of the local magnetic field between the observation epochs and tectonomagnetic anomalies. We create a temporal series of the changes in the local magnetic field for every point of the observation network on the polygon and provide the map of tectonomagnetic anomalies over different observation periods. The tectonomagnetic anomalies of 2.0—2.8 nT · year–1 were found in the Argentine Islands region. The anomalies’ spatial structure agrees with elements of the tectonic structure of the Earth crust. We studied the spatial-temporal connection of the tectonomagnetic anomalies with the region seismicity and estimated the values of tectonic stresses in the lithosphere within the piezomagnetic mechanism. The spatial-temporal structure of tectonomagnetic anomalies in the region shows the response of the geological environment to the change in the tectonic stresses in the local crust. Based on the theoretical calculations and other geological and geophysical data, we conclude that a piezomagnetic effect causes the anomalies under the action of stretching tectonic stresses (~1 bar · year–1) in the sub-latitudinal direction. Given the urgency of discovering the seismotectonic processes and current regional dynamics, the tectonomagnetic observations on the polygon should be continued as a yearly monitoring program, including other methods of geophysics and geodesy.

New sightings of the Southern right whales in West Antarctic Peninsula waters

Southern right whales (SRW) in the southwest Atlantic are recognized as slowly recovering after the massive population decline induced by harvesting. SRWs spend summer months in high-latitude feeding grounds and migrate to mid-latitude wintering grounds in autumn, where breeding occurs. Only a few sightings are known for the Antarctic waters as far south as 64° S. The West Antarctic Peninsula is a biologically productive area experiencing marine ecosystem transformations caused by climate changing at one of the fastest rates on Earth. The continental shelf of this region is important for krill stocks — a key prey source for SRW. The purpose of the present study was to reveal the austral summer and autumn presence of the SRWs in the waters of the West Antarctic Peninsula. In May—June 2009, vessel observations were made during a National Science Foundation research cruise. In March 2014, opportunistic surveys were conducted by researchers using the tour vessel as a platform of opportunity. During late March and April of 2018, January — July 2019 and March — April 2020, regular boat-based observations and vessel surveys were conducted in frames of the XXIII and XXIV Ukrainian Antarctic Expeditions, based at the Ukrainian Antarctic Akademik Vernadsky station. In our study we discuss four sightings of SRWs occurred at south of 64° S (2), and 65° S (2). On May 7, 2009, a single adult foraging SRW was sighted in Wilhelmina Bay. On March 22, 2014, an adult SRW was resting with two adult humpback whales in the northern part of the Lemaire Channel. On April 7, 2018, one SRW was sighted in a group with four humpback whales, and intensive interspecies social interactions happened. The last encounter of the SRW happened on April 24, 2020, in Gerlache Strait, near the southeastern coast of the Brabant Island — a single adult right whale was noticed while travelling. Results of our study indicate the autumn presence of some SRWs in the West Antarctic Peninsula waters — on the edge of the southern limit of known distribution for the species.

Increasing the accuracy of absolute measurements at the Argentine Islands geomagnetic observatory of the Ukrainian Antarctic Akademik Vernadsky station

Increasing the accuracy of absolute measurements at the Argentine Islands geomagnetic observatory of the Ukrainian Antarctic Akademik Vernadsky station

Antarctic planetary wave spectrum under different polar vortex conditions in 2019 and 2020 based on total ozone column data

We examine the zonal wavenumber spectrum of planetary (Rossby) waves in the atmosphere above Antarctica in each of two contrasting years: in 2019, when there was a sudden stratospheric warming (SSW), and in 2020 when the Antarctic stratospheric vortex was unusually strong and long-lived. The ozone hole (OH) is developed over Antarctica in spring, and its state depends on disturbances of the stratospheric polar vortex by planetary waves (PW). Our analysis uses data on the distribution of the total ozone column from the Ozone Monitoring Instrument on the Aura satellite and ground-based measurements from the Dobson spectrophotometer at the Ukrainian Antarctic Akademik Vernadsky station in Antarctica. The 2019 SSW strongly displaced the Antarctic vortex off-pole and aided the breakdown of the ozone hole. The SSW occurred during the peak activity of quasi-stationary planetary wave-1, which was enhanced at the time of the warming by the large amplitude of traveling wave-2. In the spring of 2020, the stratospheric polar vortex was relatively undisturbed, allowing the OH area to attain a size close to its historical maximum. A factor in 2020 that aided the stability of the vortex was the relatively small amplitude of wave-1. The stability was maintained despite regular periods when the amplitude of traveling wave-2 attained or even exceeded values around the time of the SSW in 2019. We find that a factor contributing to the differences between the wave effects in the two years is the dynamics of the quasi-stationary wave-1. Anticorrelation of the wave-1 and wave-2 amplitudes near the edge of the vortex was clearly observed in 2020, which can be caused by the transfer of planetary wave energy between different spectral wave components, unlike the situation in 2019.

Intra-annual and long-periodic components in the changes of precipitation over the Antarctic Peninsula and their possible causes


 
 
 In order to identify and study the main mechanisms of the formation of atmospheric precipitation, in the article the monthly and annual amounts of precipitation were analyzed from the observations results at Vernadsky, Bellingshausen and Grytviken stations. For the last station, a small linear trend of precipitation increase was detected, while at Vernadsky and Bellingshausen station it is practically absent. At the next stage of the study, the characteristics of intra-annual component of the precipitation variability for these stations were obtained. In the annual course, the component of precipitation variability is represented by 3 peaks – March, July and October (at Bellingshausen station March and July only), with a well-pronounced 4-year periodicity. However, data from Vernadsky station indicates a decrease of the seasonal component in time, at Grytviken station the seasonal component is stable, while at Bellingshausen station is increasing of the seasonal component in time. The analysis of long-period components of the precipitation variability of was carried out on the remains of the data obtained after the analysis of the intra-annual component. For the long-period component of precipitation variability at Vernadsky station, five statistically significant harmonics were obtained, which are reflected in periods of 6.8, 2.4, 4.0, 5.1, and 5.3 years. For Grytviken and Bellingshausen stations, 4 statistically significant harmonics were obtained, the periods of which are 4.2, 0.8, 1.7, 8.9 years and 1.5, 2.0, 2.8, 0.2 years, respectively. Today, the main phases of solar activity are well known, which are about 11 years old. The long-period components of precipitation variability obtained in the work for the stations under consideration (to 10.3, 12 and 34.1 years) are identical (close) to the mentioned phase of solar activity. This allowed the authors to draw preliminary conclusions about the influence of solar activity on the conditions for the formation of precipitation in the region under study. However, direct correlation analysis did not confirm this, as in the case of the El Niño influence.
 
 

The 16-year periodicity in the winter surface temperature variations in the Antarctic Peninsula region

The aim of this work is a comprehensive study of the 16-year periodicity of winter surface temperature in the Antarctic Peninsula (AP) region, described earlier, and its possible source based on weather station records over the 1952–2019 period making use of the Scientific Committee on Antarctic Research (SCAR) Reference Antarctic Data for Environmental Research (READER) database, as well as Fourier and wavelet analysis methods. It is shown that interdecadal oscillation with a period of about 16 years dominates in the northern AP (Esperanza and Orcadas), which is consistent with previous results. The 16-year periodicity is found to closely correlate with the sea level pressure anomaly in the southwestern Atlantic associated with the zonal wave-3 and the Southern Annular Mode patterns. The correlation maximum in the southwestern Atlantic, having the characteristic features of the anticyclonic circulation, affects the surface temperature in the northern AP through the related structure of the zonal and meridional wind anomalies. This effect is weaker to the south, where the Vernadsky station data do not show a regular interdecadal periodicity. Due to the correlated variability in the wave-3 ridges, the pronounced 16-year periods exist also in the surface temperature of southern Australia–New Zealand region, as well as in the zonal mean sea level pressure at 30°–50° S. The sea surface temperatures are much less involved in the 16-year oscillation suggesting that atmospheric rather than oceanic processes appear to be more important for its occurrence.

Prospects for the use of wind energy resources at the Akademik Vernadsky station

Renewable energy and other methods of minimizing emissions into the atmosphere should be a priority for each country. This approach should be extended to Antarctica scientific stations.The study main objective was to obtain the necessary estimates of the wind energy potential of the Galindez Island territory to estimate the feasibility of installing wind turbines on the territory of the Akademik Vernadsky station. The study of the wind properties over the territory was based on the British Antarctic Survey archive of meteorological parameter average annual values (1950–2020), 3-h wind speed and direction data, registered by the Akademik Vernadsky station (2011–2020), and average daily data from meteorological observations (2014–2018). The Hellman parameter was calculated from satellite data. A number of statistical methods were used to analyze the vertical wind profile, particularly the method of minimizing the arithmetic mean relative modeling error. To assess the amount of generation, the wind speed data at the height of the anemometer sensor were recalculated to the height of the wind turbine axis. Using the wind power characteristics provided by the developers, average annual wind power generation was avaluated. For calculations of wind energy potential, we chose the technique developed by the Department of Wind Power of the Institute of Renewable Energy of the National Academy of Sciences of Ukraine. The analysis of the wind conditions showed a high average daily wind speed (3.9 m/s) and the prevailing wind direction (north – northeast 24%). The results support the hypothesis about the expediency of installing wind turbines on the territory of the Akademik Vernadsky station. The wind turbine was selected for further wind power calculations based on the other countries experience of using wind turbines in Antarctica and considering the specifics of installation and operation in conditions of high wind speeds, low temperatures and high relative humidity. Based on information on fuel consumption at the Akademik Vernadsky station, it was estimated that the installation of 10 wind turbines SD6 would meet 28.4% of the station's yearly electricity needs.