Wildfires pose a significant environmental and socioeconomic threat to South Africa, resulting in human displacement, loss of life and livestock, and substantial infrastructure damage. Originating from both controlled agricultural burns and uncontrolled fires driven by negligence, dry conditions, and natural factors, these events contribute significantly to CO2 emissions, impacting the global greenhouse gas balance. To advance wildfire prevention, early detection, and monitoring, this study analyzes wildfire dynamics in South Africa. We investigate the impact of climate change in shaping fire regimes by analyzing burnt area data alongside meteorological parameters, revealing a strong correlation, particularly with wind speed (r = 0.68). Furthermore, the research characterizes aerosols linked to wildfire smoke. This involves analyzing Aerosol Optical Depth (AOD), which quantifies aerosol concentration, and the Angstrom Exponent (AE), which provides insights into particle size composition (high AE indicating fine, smoke-related particles). The study underscores that fire regimes are shaped by complex interactions between climate change such as high temperatures, low humidity, drought, land use and land cover types, and human activities which are responsible for up to 90

Low frequency electromagnetic waves emitted by sprite-producing lightning are normally measured using vertical electric fields or horizontal magnetic fields. Here we report for the first time the simultaneous measurement of electromagnetic waves from sprite-producing lightning in all six electromagnetic field components . A rigorous assessment of the horizontal electric field measurements with dipole antennas in two independent calibration experiments shows that a timing uncertainty of ns can be achieved, well above the current fundamental limit of the timing accuracy 1-5 ps. The coupling between the electric and magnetic fields is quantified using a transfer matrix, allowing the magnetic field to be reconstructed accurately from electric field measurements. The cross product of electric and magnetic fields is used to calculate peak energy fluxes and arrival azimuths from sprite-producing lightning. It is found that peak energy fluxes vary between 10-1,000 and that the differences between the measured and expected arrival azimuths are practically normally distributed with a mean and standard deviation of . It is concluded that horizontal electric field measurements are well suited to characterize electromagnetic waves with added benefits, including the ease of deployment in harsh environments, cost-effectiveness and scalability, for example for polarisation measurements in large low frequency arrays. The significance of this study is that it can be used as a pathfinder mission to identify critical technical requirements for the array deployment during the Africa2Moon lander mission.

Wildfires have made it to the list of environmental disasters faced by South Africa. They may result in the displacement of humans, loss of livestock, destruction of infrastructure, and have effects on weather and climate change. To minimize the loss and effects of wildfires, we need to understand the statistics of wildfires, trace back and map where most of these wildfires started. This study analyses burnt area and meteorological parameters to detect the impact of climate change in shaping fire regimes. We look at the trends and spatial distributions of the two parameters, precipitation rate and surface wind speed, and compare them with the burned area, which shows the extent of burning. We use the burn date layer of the Burnt Area, MODIS- Terra satellite dataset. The precipitation rate is obtained from the Tropical Rainfall Measuring Mission (TRMM) and the surface wind speed from Modern-Era Retrospective Analysis for Research and Applications version 2 (MERRA-2). The analysis of meteorological parameters shows the strong variations of the wind speed with the burning. The prevalence of fires in the Mpumalanga province calls for a need to characterize the spatial and temporal trends of the aerosols. This study uses remotely sensed data to analyse some of the atmospheric aerosol optical properties, the Aerosol Optical Depth (AOD), and the Angstrom Exponent (AE) that are linked to smoke from wildfires. The AOD gives information about the concentration of aerosols in the atmosphere, which can be linked to fires. AE tells us about the composition of aerosols in the atmosphere. This study uses remote sensing satellite data to track the history of wildfires in Mpumalanga, South Africa. The tracking of wildfire history is essential in the prevention, advancement of early detection, and monitoring of wildfires.

We show that Traveling Ionospheric Disturbances (TIDs) may affect the Farley Buneman Instability (FBI) and Gradient Drift Instability (GDI) echoes referred to as the Near Range Echoes (NREs) in the SuperDARN radar backscatter from the lower part of the E-region. TIDs and NREs are observed concomitantly by the Zhongshan SuperDARN radar (69.38 degrees S, 76.38 degrees E) in the far and near ranges, respectively. At the moment, there is no study about the effects of TIDs on the NREs caused by the FBI using the SuperDARN radars. The GDI are more likely to occur at a lower altitude while FBI occurs at a slightly higher altitude in the lower part of the ionospheric E-region. We use the Spearman Correlation Coefficient (SCC) to show that a part of the NREs backscatter power could be statistically explained by the MSTIDs backscatter power received by the same radar. We also investigate the simultaneous occurrence rate of the NREs and MSTIDs during the 24th solar cycle. Seasonal variability shows that MSTIDs-NREs events over Zhongshan mostly occur in summer and equinoxes during local night and morning. The majority of these events lasted between similar to 4 and similar to 8 hr. Most events disappeared early in the morning. Statistics of the Spearman correlation coefficient values show that similar to 9% of NRE amplitude modulation could be due to the MSTIDs. There are almost equal numbers of negative and positive Spearman correlation coefficient values. The relative velocity between the E-region NREs and the F-region MSTIDs switching the electric field polarities between the crests and troughs could be the cause of those equal number of the Spearman correlation coefficient values. The orientation of the ionospheric current relative to the MSTID polarization electric field may also play a significant role in the reported Spearman correlation coefficient values. We argue that in some cases, the TIDs might have been close enough to the NREs altitude to modulate them directly by transporting the plasma up and down through shear or compression. SuperDARN radar Near Range Echoes (NREs) were observed at an altitude range of 95-125 km and are caused by the Gradient Drift Instability (GDI) and Farley Buneman Instability (FBI). Medium Scale Traveling Ionospheric Disturbances (MSTIDs) are wave-like perturbations of plasma density that propagate in the ionosphere. They are caused by any major ionospheric energy input such as the Atmospheric Gravity Waves (AGWs), Joule heating, Perkins instability, and so on. It was argued that the MSTIDs partially modulate the NREs backscatter power associated with the GDI through the polarization electric field. We use the Zhongshan SuperDARN radar to show that apart from GDI, FBI related echoes are also partially modulated by the MSTIDs. We also record the number of MSTID-NRE events during 2010-2019 and found that the majority of them occurs in summer and equinoxes during local night and morning while the minority occurred in the winter of the southern hemisphere. We also perform a statistical study of the Spearman correlation coefficient values of all events recorded for this study. First demonstration of TIDs partially modulating Farley Buneman (FB) and Gradient Drift (GD) waves Farley Buneman and Gradient Drift Instabilities generate NREs Spearman rank correlation analysis shows that statistically similar to 9% of NRE amplitude modulation could be due to the MSTIDs

At Zhongshan (69 degrees S, 76 degrees E) Antarctica we investigate the sporadic E (Es)-layer virtual height modulation, observed by an ionosonde, during the passage of the Medium-Scale Traveling Ionospheric Disturbances (MSTIDs), observed by a SuperDARN radar. Two events were identified, on 04 October 2011 at 07:00- 12:00 UT and 29 February 2012 at 00:00- 04:00 UT with periods of-15.0 and-12.0 min, respectively. The magnitude of average height modulation of the Es-layer was-3.7 to-17.1 and-0.5 to-7.3 km, respectively, with the same periods as the MSTIDs. Ray tracing during the events shows that the likely MSTID propagation was up to-300 km in the ionospheric F-region. The computed ion vertical drift velocity using SuperDARN radar and magnetometer data, and Es-layer altitude modulation observed by the ionosonde have moderate to strong positive correlation of 0.71 +/- 0.22 and 0.51 +/- 0.16, respectively. We show that the MSTIDs polarization electric field, which is mapped down from the F-region along the near-vertical magnetic field, moderately contributes to the modulation of the Es layer altitude via the E x B drift mechanism.

The model used in the publication for Global simulations of multi-frequency HF signal absorption for direct observation of middle atmosphere temperature and composition This paper presents the first numerical study on a new concept for the direct measurement of D-region absorption in the HF band. Numerical simulations based on the Appleton–Hartree and Garrett equations of refractive index are presented. Electron temperature as a result of HF radio pumping of the ionosphere is included in the calculations using proper numerical formulation. Both O- and X-mode radio wave polarizations are taken into consideration. A global map of HF absorption in the northern hemisphere is calculated. Detailed calculations of HF radio wave absorption as it propagates through the lower atmosphere are presented. The effect of several parameters on the amount of absorption is calculated. The best frequencies to be used for the purpose of this study are discussed. A machine learning model is developed and the capability of the model in estimation of D and E-region constituents includes $N_2$, $O$, $O_2$, as well as $T$ and $N_e$ is examined. Such a technique can also lead to global mapping of HF absorption and improve OTHR (over-the-horizon-radar) performance.

We analyze simultaneous photometric observations of thundercloud discharges from the Modular Multispectral Imaging Array of the Atmosphere‐Space Interactions Monitor (ASIM) on board the International Space Station with ground‐based vertical electric field measurements in South Africa on 3 February 2019 at 23:00–23:05 UTC. During this time, ASIM flew over an extended thunderstorm front of several hundreds of kilometers and recorded a blue discharge with the photometer at 337 nm which emitted strong electric fields. It is found that the rising edge of the blue photomultiplier tube light pulse allows the estimation of the blue discharge height: ∼10.9–16.5 km which is constrained by cloud top height in a range of ∼13.3–16.7 km deduced from infrared radiometry on board the geostationary Meteosat satellite. The electric field measurements are used to infer the height of the blue discharge to be ∼16.0–18.8 km by use of skywave arrival times. It is shown that the height determinations are consistent with each other within the measurement uncertainties and the possible presence of an overshooting cloud top is discussed. The height of blue discharges is important to better understand how they can affect the chemistry in the upper troposphere.

Transient Luminous Events (TLEs) above thunderclouds have been previously associated with variables such as the lightning Charge Moment Change (CMC), charge height, charge transfer, and lightning current rise-time. We show for the first time a comparison of the CMC, rise-time, fall-time, peak electric field, and peak current of the lightning discharges associated with 11 column, 11 carrot, and 18 sprites with halo. We found that carrot sprites are induced by a lightning discharge with CMC, peak electric field, and peak current greater and less than that for column sprites and sprites with halo, respectively. Sprites with a halo are initiated by a lightning discharge with a longer rise-time and fall-time than that for column and carrot sprites. Column sprites top altitude and carrot sprites brightest region altitude positively correlate with lightning rise-time. For carrot sprites top altitude, the results suggest that the electrical breakdown region decreases in altitude for a longer fall-time, greater peak electric field, and greater peak current. For the altitude of the sprites brightest region, column sprites correlate negatively with lightning fall-time, peak electric field, and CMC, and column sprites top altitude also correlates negatively with lightning peak electric field. For sprites with a halo top altitude increased with lightning fall-time and peak current, and sprites with a halo brightest altitude increased with an increase in lightning CMC. Halo diameters correlate positively with lightning fall-time, peak electric field, and peak current. The investigated lightning parameters can be used to identify the initiated sprites morphological type when optics are not available.

This study presents an improved method to estimate differential energy flux, auroral power and field‐aligned current of electron precipitation from incoherent scatter radar data. The method is based on a newly developed data analysis technique that uses Bayesian filtering to fit altitude profiles of electron density, electron temperature, and ion temperature to observed incoherent scatter spectra with high time and range resolutions. The electron energy spectra are inverted from the electron density profiles. Previous high‐time resolution fits have relied on the raw electron density, which is calculated from the backscattered power assuming that the ion and electron temperatures are equal. The improved technique is applied to one auroral event measured by the EISCAT UHF radar and it is demonstrated that the effect of electron heating on electron energy spectra, auroral power, and upward field‐aligned current can be significant at times. Using the fitted electron densities instead of the raw ones may lead to wider electron energy spectra and auroral power up to 75% larger. The largest differences take place for precipitation that produces enhanced electron heating in the upper E region, and in this study correspond to fluxes of electrons with peak energies from 3 to 5 keV. Finally, the auroral power estimates are verified by comparison to the 427.8 nm auroral emission intensity, which shows good correlation. The improved method makes it possible to calculate unbiased estimates of electron energy spectra with high time resolution and thereby to study rapidly varying aurora.

Ground-based observations of the ozone (O3) emission line at 11.072 GHz have been made using the Ny Ålesund Ozone in the Mesosphere Instrument (NAOMI) at the UK Arctic Research Station (latitude 78°55’0” N, longitude 11°55’59” E). Seasonally-averaged O3 vertical profiles in the mesosphere-lower thermosphere (MLT) region from 15 August 2017 to 15 March 2020 have been retrieved over the altitude range 62–98 km. NAOMI measurements are compared with overlapping Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) satellite observations. The NAOMI and SABER data are binned into 3-month nominal ‘winter’ (15 December–15 March), ‘autumn’ (15 August–15 November), and ‘summer’ (15 April–15 July) periods. The NAOMI observations show the same year-to-year and seasonal variabilities as the SABER 9.6 µm O3 data, and winter night-time and twilight volume mixing ratio (VMR) profiles agree to within the measurement uncertainties. However, for autumn twilight conditions the SABER 9.6 µm O3 secondary maximum VMR is more than 50% higher than NAOMI. Comparing the two SABER channels which measure O3 at different wavelengths and use different processing schemes, the 9.6 μm O3 autumn twilight VMR values for 2017–19 exceed the corresponding 1.27 μm data with the largest difference (58%) in the 65–95 km altitude range similar to the NAOMI observation. Summer daytime SABER 9.6 μm mesospheric O3 VMR is also consistently higher than the 1.27 μm measurement, confirming previously reported differences between SABER 9.6 μm measurements and those made by other satellites.

Sporadic E ( E s) layers could be composed of metallic ions and formed, modified, or transported by the action of convective electric fields in the high latitude ionosphere. In this paper, by utilizing simultaneous observations from Digisonde and Super Dual Auroral Radar Network (SuperDARN) HF radars at Zhongshan Station (ZHS, 69.4°S, 76.4°E), Antarctica, a thin E s layer, which initially formed in the lower F region and descended into the lower E region, with wavelike structures, was recorded by Digisonde on 14 November 2019. The Es layer‐related concurrent ionospheric irregularities were also detected by the SuperDARN ZHS HF radar. By using a global‐scale 2‐D convection map, combined with images from the Special Sensor Ultraviolet Spectrographic Imager instruments onboard Defense Meteorological Satellite Program (DMSP) spacecraft, it is proposed that the flow shears associated with the duskside convective circulation are responsible for the evolution of the E s layer. Moreover, using the HF radar elevation angle data to measure the scatter height, it is strongly suggested that the Es layer was elongated with convection circulation. The electrodynamic processes responsible for the formation and evolution of the E s layer are discussed.

The first true common volume observations of the PMSE source region with 4 radars are presented in this paper. Radar frequencies of 8, 56, 224, and 930 MHz are used in this study. Three days of experimental observations at EISCAT are presented. Numerical simulations of mesospheric dusty/ice plasma associated with the observed radar frequencies are presented. The effect of neutral air turbulence on the generation and strength of plasma density perturbations associated with PMSE using four radar frequencies and in the presence of various dust parameters is investigated. Using the model it is shown that the well‐known neutral air turbulence in the presence of heavy dust particles and neutral air turbulence combined with dust density (dusty turbulence) can largely explain the observed radar cross‐section at four radar frequencies. The effect of neutral air turbulence amplitude along with dust charging and diffusion in the presence of various dust parameters is investigated using the computational model. Specifically, the response of diffusion to charging time scales, plasma density fluctuation amplitude and background dusty plasma parameters are discussed. Several key parameters in the dusty plasma responsible for the PMSE observations are determined. Qualitative comparison of radar echo strength at 4 frequencies with numerical results is provided. Unlike the previous studies that required large dust particles of 20 nm for PMSE formation, the present work demonstrates the possibility of small dust particles to explain the experimental observations.

The Antarctic and Arctic regions are Earth's open windows to outer space. They provide unique opportunities for investigating the troposphere–thermosphere–ionosphere–plasmasphere system at high latitudes, which is not as well understood as the mid- and low-latitude regions mainly due to the paucity of experimental observations. In addition, different neutral and ionised atmospheric layers at high latitudes are much more variable compared to lower latitudes, and their variability is due to mechanisms not yet fully understood. Fortunately, in this new millennium the observing infrastructure in Antarctica and the Arctic has been growing, thus providing scientists with new opportunities to advance our knowledge on the polar atmosphere and geospace. This review shows that it is of paramount importance to perform integrated, multi-disciplinary research, making use of long-term multi-instrument observations combined with ad hoc measurement campaigns to improve our capability of investigating atmospheric dynamics in the polar regions from the troposphere up to the plasmasphere, as well as the coupling between atmospheric layers. Starting from the state of the art of understanding the polar atmosphere, our survey outlines the roadmap for enhancing scientific investigation of its physical mechanisms and dynamics through the full exploitation of the available infrastructures for radio-based environmental monitoring.

We present the first observations from SuperDARN HF radar data of E ‐region Near Range Echoes (NREs) whose amplitudes are partially modulated by Medium‐Scale Traveling Ionospheric Disturbances (MSTIDs) propagating in the F ‐region overhead that have been observed by the same radar in the far ranges. SuperDARN NREs occur normally ∼180–315 km downrange from the radar at ∼95–125 km altitude. Selected observations of TID‐modulated NREs are presented from SANAE and Zhongshan Antarctic SuperDARN radars for both summer and winter seasons as well as geomagnetic active and quiet times. We show that the most likely mechanism is partial modulation of the Gradient Drift Instability (GDI), which is responsible for producing the NREs. GDI is driven by the velocity difference between neutrals and ions and may appear in the E ‐region ionosphere wherever suitable plasma density gradients exist. GDI already present in the E ‐region can be partially modulated by an MSTID passing overhead in the F ‐region via the additional MSTID polarization electric field mapped down in altitude along the equipotential magnetic field lines, thereby partially modulating the NRE amplitudes as observed.

Recently, Transient Luminous Events (TLEs) in the mesosphere and lightning activity near thunderstorm tops have attracted great interest. The Atmosphere-Space Interactions Monitor (ASIM) and the Modular Multispectral Imaging Array (MMIA) are on board the International Space Station (ISS) to record the lightning activity and TLEs in the UV band (180-230 nm) as well as the blue (337 nm) and the red (777.4 nm) emissions (Chanrion et al. [2019], Neubert et al. [2019]). Blue luminous events recorded by ASIM during the nighttime were first reported by Soler et al. [2021]. During 23:00-23:05 UTC on 3rd, February 2019, 188 MMIA triggers were recorded and more than 2000 lightning strokes were reported by the lightning detection and location network. We focus on a blue discharge event that happened at 23:02:41 UTC, which was caused by a negative narrow bipolar event (NBE) with no red and UV photomultiplier tube (PMT) pulses associated with it. The novelty of this work is that the height determination is carried out by using the ground-based electric field measurements and the space-based optical measurements from ASIM. The low-frequency electric field receiver was set up in Carnarvon, 30.97° S, 21.98° E, South Africa. The blue discharge height (15.83-18.67 km), calculated using the electric field measurements, is derived from the skywaves arrival times with a spherical Earth model. The ionospheric height calculated by this model (93.89 km) is consistent with that determined by the averaged cloud to ground discharges waveforms (93.68 km). The rising edge of the blue optical emission is analyzed to do the altitude estimation (14.3-15.8 km). The cloud top height is calculated as a reference (15.75-16.65 km), which is inferred from radiometric measurements, typically at a wavelength around 10 μm. The height of NBEs is important to help to understand the chemistry effects at the tropopause level caused by such events. In the future, this data set would be used to study other properties of many events such as blue events and red events. References Chanrion, O., Neubert, T., Lundgaard Rasmussen, I. et al. The Modular Multispectral Imaging Array (MMIA) of the ASIM Payload on the International Space Station. Space Sci Rev 215, 28 (2019). https://doi.org/10.1007/s11214-019-0593-y Neubert, T., Østgaard, N., Reglero, V. et al. The ASIM Mission on the International Space Station. Space Sci Rev 215, 26 (2019). https://doi.org/10.1007/s11214-019-0592-z Soler, S., Gordillo-Vázquez, F. J., Pérez-Invernón, F. J., Luque, A., Li, D., Neubert, T., et al. (2021). Global frequency and geographical distribution of nighttime streamer corona discharges (BLUEs) in thunderclouds. Geophysical Research Letters, 48, e2021GL094657. https://doi.org/10.1029/2021GL094657

Abstract Black auroras are small-scale features embedded in the diffuse background aurora, typically occurring post-substorm after magnetic midnight and with an eastward drift imposed. Black auroras show a significant reduction in optical brightness compared to the surrounding diffuse aurora, and can appear as slow-moving arcs or rapidly-moving patches and arc segments. We report, for the first time, an even more elusive small-scale optical structure that has always been observed occurring paired with $$\sim$$ ∼ 10% of black aurora patches. A patch or arc segment of enhanced luminosity, distinctly brighter than the diffuse background, which we name the anti-black aurora, may appear adjacent to the black aurora. The anti-black aurora is of similar shape and size, and always moves in parallel to the drifting black aurora, although it may suddenly switch sides for no apparent reason. The paired phenomenon always drifts with the same average speed in an easterly direction. From the first dual-wavelength (427.8 nm and 844.6 nm) optical observations of the phenomenon recorded on 12 March 2016 outside Tromsø Norway, we show that the anti-black and black auroras have a higher and lower mean energy, respectively, of the precipitating electrons compared to the diffuse background.

Sprites are mesospheric optical emissions that are mostly produced by large, positive cloud-to-ground lightning discharges. Sprites appear in different morphologies such as carrot, jellyfish and column, and are typically in the altitude range of ~40–100 km above the Earth’s surface. Sprites are a subset of transient luminous events and they contribute to the global electric circuit. South Africa has large convective thunderstorms, which typically occur in the summer months of every year. Peak current, time and geographical position of lightning strokes were obtained from the South African Weather Service. Sprite observations were recorded in South Africa for the first time on 11 January 2016 from Sutherland in the Northern Cape using a night-vision television camera from the South African National Space Agency’s Optical Space Research laboratory. We report the first estimates of the top altitude, and the altitude of maximum brightness, of 48 sprites over South Africa. We found that the average top altitude and the altitude of maximum brightness of sprites are approximately 84.3 km and 69 km, respectively, which is consistent with estimates made elsewhere. We also found a moderately high positive and a weak positive correlation between the top altitude and the altitude of maximum brightness, respectively, of sprites and the lightning stroke charge moment change. Significance: We present the first altitude estimation of sprites observed over Africa. The altitude of sprites observed over South Africa is in agreement with observations made elsewhere. There is a positive correlation between the top altitude of sprites and the parent lightning charge moment change. Sprite maximum brightness is observed near the stratopause.

Ground-based observations of 11.072 GHz atmospheric ozone (O3) emission have been made using the Ny-Ålesund Ozone in the Mesosphere Instrument (NAOMI) at the UK Arctic Research Station (latitude 78∘55′0′′ N, longitude 11∘55′59′′ E), Spitsbergen. Seasonally averaged O3 vertical profiles in the Arctic polar mesosphere–lower thermosphere region for night-time and twilight conditions in the period 15 August 2017 to 15 March 2020 have been retrieved over the altitude range 62–98 km. NAOMI measurements are compared with corresponding, overlapping observations by the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) satellite instrument. The NAOMI and SABER version 2.0 data are binned according to the SABER instrument 60 d yaw cycles into nominal 3-month “winter” (15 December–15 March), “autumn” (15 August–15 November), and “summer” (15 April–15 July) periods. The NAOMI observations show the same year-to-year and seasonal variabilities as the SABER 9.6 µm O3 data. The winter night-time (solar zenith angle, SZA ≥ 110∘) and twilight (75∘ ≤ SZA ≤ 110∘) NAOMI and SABER 9.6 µm O3 volume mixing ratio (VMR) profiles agree to within the measurement uncertainties. However, for autumn twilight conditions the SABER 9.6 µm O3 secondary maximum VMR values are higher than NAOMI over altitudes 88–97 km by 47 % and 59 %, respectively in 2017 and 2018. Comparing the two SABER channels which measure O3 at different wavelengths and use different processing schemes, the 9.6 µm O3 autumn twilight VMR data for the three years 2017–2019 are higher than the corresponding 1.27 µm measurements with the largest difference (58 %) in the 65–95 km altitude range similar to the NAOMI observation. The SABER 9.6 µm O3 summer daytime (SZA < 75∘) mesospheric O3 VMR is also consistently higher than the 1.27 µm measurement, confirming previously reported differences between the SABER 9.6 µm channel and measurements of mesospheric O3 by other satellite instruments.

PurposeThe purpose of this paper is to design, build and test a low power high frequency (HF) transmitter that can be received by the Super Dual Auroral Radar Network (SuperDARN) radar installed at SANAE IV, the 4th South African National Antarctic Expedition Station. It is proposed that it may be possible to do propagation studies using the radar and the fixed frequency, ground-based HF transmitter beacon. Interpretation of the measurements can be used to study the ionosphere, especially Travelling Ionospheric Disturbances, which are signatures of atmospheric gravity waves.Design/methodology/approachIn the absence of the actual deployment of the HF transmitter beacon in Antarctica, extensive simulations have been done to evaluate the expected performance of the transmitter in relation to the SuperDARN. A field trial has been executed between Hermanus (34.4241° S, 19.2247° E) and Pretoria (34.0558° S, 18.4589° E) in South Africa. In future, the beacon will be placed at the South Pole with its antenna radiating towards SANAE IV.FindingsThe HF transmitter conforms to the power and frequency stability requirements both during propagation tests conducted between Hermanus and Pretoria, as well as when the device was exposed to temperatures that ranged from +40°C to −45°C in a thermal chamber. Propagation in Antarctica is expected to differ from the field tests conducted due to the differences in density and dynamics of the polar ionosphere, compared to the mid-latitude ionosphere.Originality/valueSpace weather research, including forecasting atmospheric gravity waves and determining the expected electron density profile of the ionosphere, is of great scientific interest. The data received from the HF beacon can be used to study and characterize the ionosphere of the region between the South Pole and SANAE IV. Parameters of the ionosphere, such as electron density, geomagnetic storm effects, ionospheric motions and sky wave propagation paths will be better understood from analysing the signal received from this transmitter after it has been reflected and refracted by the ionosphere.