MIST

Magnetosphere, Ionosphere and Solar-Terrestrial

Latest news

Winners of Rishbeth Prizes 2023

We are pleased to announce that following Spring MIST 2023 the Rishbeth Prizes this year are awarded to Sophie Maguire (University of Birmingham) and Rachel Black (University of Exeter).

Sophie wins the prize for the best MIST student talk which was entitled “Large-scale plasma structures and scintillation in the high-latitude ionosphere”. Rachel wins the best MIST poster prize, for a poster entitled “Investigating different methods of chorus wave identification within the radiation belts”. Congratulations to both Sophie and Rachel!

As prize winners, Sophie and Rachel will be invited to write articles for Astronomy & Geophysics, which we look forward to reading.

MIST Council extends their thanks to the University of Birmingham for hosting the Spring MIST meeting 2023, and to the Royal Astronomical Society for their generous and continued support of the Rishbeth Prizes.

Nominations for MIST Council

We are pleased to open nominations for MIST Council. There are two positions available (detailed below), and elected candidates would join Beatriz Sanchez-Cano, Jasmine Kaur Sandhu, Andy Smith, Maria-Theresia Walach, and Emma Woodfield on Council. The nomination deadline is Friday 26 May.

Council positions open for nomination

  • MIST Councillor - a three year term (2023 - 2026). Everyone is eligible.
  • MIST Student Representative - a one year term (2023 - 2024). Only PhD students are eligible. See below for further details.

About being on MIST Council


If you would like to find out more about being on Council and what it can involve, please feel free to email any of us (email contacts below) with any of your informal enquiries! You can also find out more about MIST activities at mist.ac.uk.

Rosie Hodnett (current MIST Student Representative) has summarised their experience on MIST Council below:
"I have really enjoyed being the PhD representative on the MIST council and would like to encourage other PhD students to nominate themselves for the position. Some of the activities that I have been involved in include leading the organisation of Autumn MIST, leading the online seminar series and I have had the opportunity to chair sessions at conferences. These are examples of what you could expect to take part in whilst being on MIST council, but the council will welcome any other ideas you have. If anyone has any questions, please email me at This email address is being protected from spambots. You need JavaScript enabled to view it..”

How to nominate

If you would like to stand for election or you are nominating someone else (with their agreement!) please email This email address is being protected from spambots. You need JavaScript enabled to view it. by Friday 26 May. If there is a surplus of nominations for a role, then an online vote will be carried out with the community. Please include the following details in the nomination:
  • Name
  • Position (Councillor/Student Rep.)
  • Nomination Statement (150 words max including a bit about the nominee and your reasons for nominating. This will be circulated to the community in the event of a vote.)
 
MIST Council contact details

Rosie Hodnett - This email address is being protected from spambots. You need JavaScript enabled to view it.
Mathew Owens - This email address is being protected from spambots. You need JavaScript enabled to view it.
Beatriz Sanchez-Cano - This email address is being protected from spambots. You need JavaScript enabled to view it.
Jasmine Kaur Sandhu - This email address is being protected from spambots. You need JavaScript enabled to view it.
Andy Smith - This email address is being protected from spambots. You need JavaScript enabled to view it.
Maria-Theresia Walach - This email address is being protected from spambots. You need JavaScript enabled to view it.
Emma Woodfield - This email address is being protected from spambots. You need JavaScript enabled to view it.
MIST Council email - This email address is being protected from spambots. You need JavaScript enabled to view it.

RAS Awards

The Royal Astronomical Society announced their award recipients last week, and MIST Council would like to congratulate all that received an award. In particular, we would like to highlight the following members of the MIST Community, whose work has been recognised:
  • Professor Nick Achilleos (University College London) - Chapman Medal
  • Dr Oliver Allanson (University of Birmingham) - Fowler Award
  • Dr Ravindra Desai (University of Warwick) - Winton Award & RAS Higher Education Award
  • Professor Marina Galand (Imperial College London) - James Dungey Lecture

New MIST Council 2021-

There have been some recent ingoings and outgoings at MIST Council - please see below our current composition!:

  • Oliver Allanson, Exeter (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2024 -- Chair
  • Beatriz Sánchez-Cano, Leicester (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2024
  • Mathew Owens, Reading (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2023
  • Jasmine Sandhu, Northumbria (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2023 -- Vice-Chair
  • Maria-Theresia Walach, Lancaster (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2022
  • Sarah Badman, Lancaster (This email address is being protected from spambots. You need JavaScript enabled to view it.), to 2022
    (co-opted in 2021 in lieu of outgoing councillor Greg Hunt)

Charter amendment and MIST Council elections open

Nominations for MIST Council open today and run through to 8 August 2021! Please feel free to put yourself forward for election – the voting will open shortly after the deadline and run through to the end of August. The positions available are:

  • 2 members of MIST Council
  • 1 student representative (pending the amendment below passing)

Please email nominations to This email address is being protected from spambots. You need JavaScript enabled to view it. by 8 August 2021. Thank you!

Charter amendment

We also move to amend the following articles of the MIST Charter as demonstrated below. Bold type indicates additions and struck text indicates deletions. Please respond to the email on the MIST mailing list before 8 August 2021 if you would like to object to the amendment; MIST Charter provides that it will pass if less than 10% of the mailing list opposes its passing. 

4.1  MIST council is the collective term for the officers of MIST and consists of six individuals and one student representative from the MIST community.

5.1 Members of MIST council serve terms of three years, except for the student representative who serves a term of one year.

5.2 Elections will be announced at the Spring MIST meeting and voting must begin within two months of the Spring MIST meeting. Two slots on MIST council will be open in a given normal election year, alongside the student representative.

5.10 Candidates for student representative must not have submitted their PhD thesis at the time that nominations close.

Nuggets of MIST science, summarising recent papers from the UK MIST community in a bitesize format.

If you would like to submit a nugget, please fill in the following form: https://forms.gle/Pn3mL73kHLn4VEZ66 and we will arrange a slot for you in the schedule. Nuggets should be 100–300 words long and include a figure/animation. Please get in touch!
If you have any issues with the form, please contact This email address is being protected from spambots. You need JavaScript enabled to view it.. 

Global dynamical network of the spatially correlated Pc2 wave response for the 2015 St. Patrick's Day storm

By Shahbaz Chaudhry (University of Warwick)

Space weather poses a risk to infrastructure including satellites and power systems. A key challenge within space weather is predicting the magnetospheric response during storms. In order to understand the dynamics of geomagnetic storms, we can study Pc waves which are field line resonances along closed field lines in the inner magnetosphere. Recently, SuperMAG and Intermagnet have released new second resolution data which allows higher frequency Pc2 (T=5-10s) waves to be resolved and studied globally. Generation mechanisms for Pc2 waves (which we focus on in this paper) include ion-cyclotron resonance at equatorial regions of the magnetosphere.

To better understand geomagnetic storms, we for the first time build a Pc2 wave dynamical network using the full set of 100+ ground-based magnetometer stations. A network graphs the connections (edges) between entities (nodes). An example includes airline networks, where the nodes are airports and edges are flight paths. Here we build dynamical networks where nodes and edges are time varying. Network edges will be built upon the cross-correlation between Pc2 waves observed magnetic field at pairs of ground-based magnetometer stations.

Our first results are a study of the 2015 St. Patrick's Day storm for an 8 hour time window around onset. Using this storm we have identified network parameters and have shown that these track the distinct phases of the storm in terms of spatial coherence of Pc2 wave activity. We show that the network responds to distinct phase of the storm, including southward or northward IMF and does not just track the average Pc2 power. Using these network parameters we can perform statistical studies across many storms and quantitatively benchmark space weather models with observations. In addition, this analysis can be easily extended to other Pc bands which have different generation mechanisms within the magnetosphere.

Network snapshot at storm onset for the northern magnetic field component comprising 81 stations. Throughout panels (a)-(d), four groups of connections are shown, all connections (green), superimposed are connections spanning MLT<4 h (orange), north-south connections spanning MLT<4 h (purple), and pseudo-chains (blue). Panel (d) shows connections plotted in geomagnetic coordinates. Panels (a) and (b) show connections plotted in geographic coordinates and limited to the southern and northern hemispheres respectively. The global degree distribution for the given network snapshot is shown in (b) with colors corresponding to network edges in panels (a), (b), and (d).
Figure showing network snapshot at storm onset for the northern magnetic field component comprising 81 stations. Throughout panels (a)-(d), four groups of connections are shown, all connections (green), superimposed are connections spanning MLT<4 h (orange), north-south connections spanning MLT<4 h (purple), and pseudo-chains (blue). Panel (d) shows connections plotted in geomagnetic coordinates. Panels (a) and (b) show connections plotted in geographic coordinates and limited to the southern and northern hemispheres respectively. The global degree distribution for the given network snapshot is shown in (b) with colours corresponding to network edges in panels (a), (b), and (d).

 

See paper for full details: Chaudhry, S.Chapman, S. C.Gjerloev, J., & Beggan, C. D. (2023). Global dynamical network of the spatially correlated Pc2 wave response for the 2015 St. Patrick's Day stormJournal of Geophysical Research: Space Physics128, e2022JA031175. https://doi.org/10.1029/2022JA031175

Formation and Motion of Horse Collar Aurora Events

By Gemma Bower (University of Leicester)

Horse collar aurora (HCA) are an auroral phenomena that occurs under northward IMF where the polar cap becomes teardrop shaped due to the poleward motion of the dusk and dawn sectors of the auroral oval. Their formation has been linked to prolonged periods of dual-lobe reconnection (DLR). This occurs when the same IMF magnetic field line reconnects in both the northern and southern hemisphere lobes when the IMF clock angle is small. This leads to the closure of magnetic flux at the dayside magnetopause. In order to further study the motion of HCA a list of HCA events previously identified in UV images captured by the Special Sensor Ultraviolet Spectrographic Imager (SSUSI) instrument on-board the Defense Meteorological Satellite Program (DMSP) spacecraft F16, F17 and F18 has been used. Events that have concurrent 630.0 nm all-sky camera (ASC) data from the Redline Geospace Observatory (REGO) Resolute Bay site are studied in more detail, making use of the higher cadence of the ASC images compared to DMSP/SSUSI. 11 HCA events are classified based on the IMF conditions at the end of the event. A southward turning of the IMF ends five events, two end with positive By dominated IMF and four with negative By dominance. The figure shows one of the studied events that ends with a southward turning of the IMF. Under positive (negative) By the arcs move duskward (dawnward) in the northern hemisphere with the opposite true in the southern hemisphere. Under a southward turning the arcs move equatorward. These results are in agreement with previously proposed models. Understanding the evolution of HCA will allow DLR to be studied in more detail.

Figure 1: One of the studied events. The top panels show the keograms of the ASC and the relevant interplanetary magnetic field (IMF) data for the event. The first row of the columns shows the DMSP/IDM flows with an inset showing the IMF clock angle at the time of the SSUSI image. The second row is the LBHs SSUSI image on a log scale. The third row is the SSUSI image centred on the Taloyoak ASC station with the available ASC images projected on top. The final rows are the ASC images with north located at the top of each image plotted on a log scale. The UT given is the time of the ASC image and the most poleward point of the DMSP pass.
Figure 1: One of the studied events. The top panels show the keograms of the ASC and the relevant interplanetary magnetic field (IMF) data for the event. The first row of the columns shows the DMSP/IDM flows with an inset showing the IMF clock angle at the time of the SSUSI image. The second row is the LBHs SSUSI image on a log scale. The third row is the SSUSI image centred on the Taloyoak ASC station with the available ASC images projected on top. The final rows are the ASC images with north located at the top of each image plotted on a log scale. The UT given is the time of the ASC image and the most poleward point of the DMSP pass.


Please see paper for full details: Bower, Bower, G. E., Milan, S. E., Paxton, L. J., Spanswick, E., & Hairston, M. R. (2023). Formation and motion of horse collar aurora events. Journal of Geophysical Research: Space Physics, 128, e2022JA031105. https://doi.org/10.1029/2022JA031105

Will Space Weather Delay Your Train? – Modelling the Impact of Geomagnetically Induced Currents on Electrified Railway Signaling Systems in the United Kingdom

By Cameron Patterson (Lancaster University)

Railway signalling is one of the many ground-based systems that are susceptible to the impacts of space weather. A popular signalling system is the track circuit, where a line is split into smaller sections called ‘blocks’, each containing a power supply and a relay that sets the signal based on the level of current. Currents induced in the rails during geomagnetic events disrupt this balance, and have the potential to cause signalling misoperations, which can create delays and/or possibly be hazardous. Using recent theoretical work and parameters from industry standards documents, we have developed realistic models of two railway lines in the United Kingdom to study the impacts that geomagnetically induced currents have on signalling systems. In this study, we have focused on right side failures, which is when there are no trains occupying the blocks and green signals are turned red. Our results show that the susceptibility of a track circuit to induced currents is dependent on its length, orientation and position along the line. We found that the threshold electric field strength for a misoperation to occur is approximately what would arise during a storm expected to occur once every 30 years. Finally, we showed that with a 1 in 100 year extreme electric field, there would be a significant number of misoperations across the line.

 

Figure 1. The current through each of the track circuit relays between Glasgow to Edinburgh with (a) no geoelectric field applied, (b) at the threshold for misoperation, and (c) at the estimated electric field strength for a 1 in 100 year event. The green circles indicate the current of each relay, the red (solid) line shows the current value below which the track circuit would de-energize and display an incorrect signal, and the green (dashed) line shows the level that the current would need to rise above to re-energize if de-energized. An unfilled green circle means normal operation, and a filled red circle indicates a misoperation.

 

Please see the following paper for a more in depth look: Patterson, C. J., Wild, J. A., & Boteler, D. H. (2023). Modeling the impact of geomagnetically induced currents on electrified railway signaling systems in the United Kingdom. Space Weather, 21, e2022SW003385. https://doi.org/10.1029/2022SW003385.

Extreme Event Statistics in Dst, SYM-H, and SMR Geomagnetic Indices

Aisling Bergin (University of Warwick)

Extreme space weather events are rare, and quantifying their likelihood relies upon long-term continuous observations. High-quality ground-based magnetometer observations underpin geomagnetic indices that monitor space weather and span multiple solar cycles. The Dst index ring-current monitor, derived from an hourly average over four low-latitude stations, is a benchmark for extreme space weather events, and has been extensively studied statistically. Space weather storms cause magnetic perturbation that can be localized in space and time. Geomagnetic ring current indices are available which use a larger number of magnetometers than Dst: SYM-H (derived from 6 stations) and SuperMAG SMR (derived from up to 120 stations).

In this paper we perform the first extreme value theory (EVT) analysis of SYM-H and SMR. EVT analysis reveals a divergence between the return level found for Dst, and those for SYM-H and SMR, that increases non-linearly with return period. For return periods below 10 years, hourly averaged SYM-H and SMR have return levels similar to Dst, but at return periods of 50 and 100 years, they respectively exceed that of Dst by about 10% and 15% (SYM-H) and about 7% and 12% (SMR). One minute resolution SYM-H and SMR return levels progressively exceed that of Dst; their 5, 10, 50, and 100 year return levels exceed that of Dst by about 10%, 12%, 20% and 25% respectively. Our results indicate that consideration should be given to the differences between the indices if selecting one to use as a benchmark in model validation or resilience planning for the wide range of space weather sensitive systems that underpin our society.


Figure 1. Comparison of event return levels across geomagnetic indices. Empirical estimates of the return levels for peak-over-threshold values are compared for (a) Dst (blue), hourly average SMR (orange), and hourly average SYM-H indices (pink), and (b) Dst (blue), 1-minute SMR (green), and 1-minute SYM-H indices (red). For each index, extreme value theory return level estimates (solid line) with 95% confidence intervals (shaded) are plotted.

 

Please see the paper for full details: Bergin, A., Chapman, S. C., Watkins, N. W., Moloney, N. R., & Gjerloev, J. W. (2023). Extreme event statistics in Dst, SYM-H, and SMR geomagnetic indices. Space Weather, 21, e2022SW003304. https://doi.org/10.1029/2022SW003304

The predictive power of magnetospheric models for estimating ground magnetic field variation in the United Kingdom

Ewelina Florczak (British Geological Survey, University of Edinburgh)

Space weather events can have damaging effects on ground-based infrastructure. Geomagnetically induced currents caused by rapid magnetic field fluctuations during geomagnetic storms can negatively affect power networks, railways as well as navigation systems. To reduce such negative impacts, good forecasting capability is essential. In this study we assess the performance of contemporary magnetohydrodynamic (MHD) models in predicting the ground magnetic field perturbations at three UK observatories during two severe space weather events: September 2017 and March 2015. Simulated magnetic data were acquired via Community Coordinated Modeling Center1, using the following models: Space Weather Modeling Framework (SWMF), Open Geospace General Circulation Model (Open GGCM) and Lyon–Fedder–Mobarry (LFM) combined with the Rice Convection Model (RCM). Qualitative and quantitative comparison between measured and modelled values suggest that the performance of MHD models vary with latitude, the magnetic component and the characteristics of the storm analysed. Most models tend to exaggerate the magnitude of disturbances at lower latitudes but better capture the fluctuations at the highest latitude. For the two storms investigated, the addition of RCM tends to result in overestimation of the amplitude of ground perturbations. The observed data-model discrepancies most likely arise due to the many approximations required in MHD modelling, such as simplified solar wind input or shift in location of the electrojets in the simulated magnetospheric and ionospheric currents. It was found that no model performs consistently better than any other, implying that each simulation forecasts different aspects of ground perturbations with varying level of accuracy. Ultimately, the decision of which model is most suitable depends on specific needs of the potential end user.

 

Six panels showing northward ground magnetic field component (Bx) at Hartland (HAD) in Devon, Eskdalemuir (ESK) in the Southern Uplands of Scotland and Lerwick (LER) in the Shetland Islands during 7–8 September 2017 (event 1, left), and 17–18 March 2015 (event 2, right). Black line is the measured observatory values, coloured lines correspond to respective CCMC models.
Figure 1: Northward ground magnetic field component (Bx) at Hartland (HAD) in Devon, Eskdalemuir (ESK) in the Southern Uplands of Scotland and Lerwick (LER) in the Shetland Islands during 7–8 September 2017 (event 1, left), and 17–18 March 2015 (event 2, right). Black line is the measured observatory values, coloured lines correspond to respective CCMC models.

References:

  1. Runs on Request | CCMC (nasa.gov)

For further details see Florczak E, Beggan CD and Whaler KA (2023) The predictive power of magnetospheric models for estimating ground magnetic field variation in the United Kingdom. Front. Astron. Space Sci. 10:1095971. doi: 10.3389/fspas.2023.1095971