About

My primary scientific expertise is in Birkeland currents, which play a key role in space weather effects on Earth. They are electrical currents which flow between the boundaries of the Earth's magnetic field and the Earth's atmosphere. When the Sun's activity affects the Earth, it is Birkeland currents that relay the effects to the ground, where the impacts can be felt on ground-based infrastructure.

Prior to joining Northumbria University in 2022, I was at the University of Southampton from 2015–2022, during which time I worked on Birkeland currents as well as working on substorms and Northward IMF dynamics. I obtained my PhD and first-class MPhys at the University of Leicester between 2007–2015.

In my other endeavours, I have extensive public engagement experience as PI of the Southampton Planeterrella. I was Chair of MIST Council in 2019–21, and I am on the STFC PEER Forum review panel.

You can visit my staff page on Northumbria University’s website, or visit my page on Northumbria University’s Research Portal for more details about me and my research.

Career

Notable achievements

Academic history

  • 2022–present: STFC Ernest Rutherford Fellow, Northumbria University
  • 2016–2021: Postdoctoral research with Rob Fear, University of Southampton
  • 2015–2016: Postdoctoral research with Caitriona Jackman, University of Southampton
  • 2012–2015: PhD research with Steve Milan, University of Leicester
  • 2007–2011: MPhys in Physics with Astrophysics, University of Leicester

Papers

2025

  1. Maria-Theresia Walach, Alexandra R Fogg, John C Coxon, Adrian Grocott, Steve E Milan, Harneet K Sangha, Kathryn A McWilliams, Sarah K Vines, Mark Lester & Brian J Anderson (2025). Reliability of matching AMPERE field-aligned current boundaries with SuperDARN lower latitude ionospheric convection boundaries during geomagnetic storms, Journal of Geophysical Research: Space Physics, 150, e2024JA033253. https://doi.org/10.1029/2024JA033253.

2024

  1. Denny M Oliveira, James M Weygand, John C Coxon & Eftyhia Zesta (2024). Substorm-time ground dB/dt variations controlled by interplanetary shock impact angles: A statistical study, Space Weather, 22, e2023SW003767. https://doi.org/10.1029/2023SW003767.

  2. Christopher J Scott, Matthew N Wild, Luke A Barnard, Bingkun Yu, Tatsuhiro Yokoyama, Michael Lockwood, Cathryn N Mitchell, John C Coxon & Andrew J Kavanagh (2024). Calibrating estimates of ionospheric long-term change, Annales Geophysicae, 42, 395–418. https://doi.org/10.5194/angeo-42-395-2024.

  3. Andrew W Smith, I Jonathan Rae, Colin Forsyth, John C Coxon, Maria-Theresia Walach, Christian J Lao, D Shaun Bloomfield, Sachin A Reddy, Mike K Coughlan, Amy Keesee & Sarah N Bentley (2024). Space weather forecasts of ground level space weather in the UK: Evaluating performance and limitations, Space Weather, 22, e2024SW003973. https://doi.org/10.1029/2024SW003973.

2023

  1. John C Coxon, Gareth Chisham, Mervyn P Freeman, Colin Forsyth, Maria-Theresia Walach, Kyle R Murphy, Sarah K Vines, Brian J Anderson, Andrew W Smith & Alexandra R Fogg (2023). Extreme Birkeland currents are more likely during geomagnetic storms on the dayside of the Earth, Journal of Geophysical Research: Space Physics, 128, e2023JA031946. https://doi.org/10.1029/2023JA031946.

  2. Angeline G Burrell, McArthur Jones Jr, Kate A Zawdie, John C Coxon & Alexa J Halford (2023). Tips for writing a good recommendation letter, Frontiers in Astronomy and Space Sciences, 10. https://doi.org/10.3389/fspas.2023.1114821.

  3. Laura J Fryer, Robert C Fear, Imogen L Gingell, John C Coxon, Minna Palmroth, Sanni Hoilijoki, Pekka Janhunen, Anita Kullen & Paul A Cassak (2023). 3D GUMICS simulations of northward IMF magnetotail structure, Journal of Geophysical Research: Space Physics, 128, e2023JA031317. https://doi.org/10.1029/2023JA031317.

  4. James E Waters, Caitriona M Jackman, Daniel K Whiter, Alexandra R Fogg, Laurent Lamy, Jennifer A Carter, John C Coxon, Laura Fryer, Corentin K Louis, Larry J Paxton, Carine Briand, Baptiste Cecconi, Karine Issautier, Xavier Bonnin, & Peter T Gallagher (2023). Auroral emissions and inner magnetospheric dynamics during Earth’s response to the 28th October 2021 Coronal Mass Ejection, in Planetary, Solar and Heliospheric Radio Emissions IX (eds Corentin K Louis, Caitriona M Jackman, Georg Fischer, Ali H Sulaiman & Pietro Zucca), 155–170. https://doi.org/10.25546/104047.

2022

  1. John C Coxon, Gareth Chisham, Mervyn P Freeman, Brian J Anderson & Robert C Fear (2022). Distributions of Birkeland current density observed by AMPERE are heavy-tailed or long-tailed, Journal of Geophysical Research: Space Physics, 127, e2021JA029801. https://doi.org/10.1029/2021JA029801.

  2. Joseph WB Eggington, John C Coxon, Robert M Shore, Ravindra T Desai, Lars Mejnertsen, Jeremy P Chittenden & Jonathan P Eastwood (2022). Response timescales of the magnetotail current sheet during a geomagnetic storm: Global MHD simulations, Frontiers in Astronomy and Space Sciences, 9, 966164. https://doi.org/10.3389/fspas.2022.966164.

2021

  1. John C Coxon, Robert C Fear, Jade A Reidy, Laura J Fryer & James Plank (2021). Hot plasma in the magnetotail lobe shows characteristics consistent with closed field lines trapped in the lobes, Journal of Geophysical Research: Space Physics, 126, e2021JA029516. https://doi.org/10.1029/2021JA029516.

  2. Laura J Fryer, Robert C Fear, John C Coxon & Imogen L Gingell (2021). Observations of closed magnetic flux embedded in the lobes during periods of Northward IMF, Journal of Geophysical Research: Space Physics, 126, e2021JA029281. https://doi.org/10.1029/2021JA029281.

2020

  1. Mike Lockwood, Mathew J Owens, Luke A Barnard, Clare EJ Watt, Chris J Scott, John C Coxon & Kathryn A McWilliams (2020). Semi‐annual, annual and Universal Time variations in the magnetosphere and in geomagnetic activity: 3. Modelling, Journal of Space Weather and Space Climate, 10, 61. https://doi.org/10.1051/swsc/2020062.

  2. Mike Lockwood, Kathryn A McWilliams, Mathew J Owens, Luke A Barnard, Clare EJ Watt, Chris J Scott, Allan R Macneil & John C Coxon (2020). Semi-annual, annual and Universal Time variations in the magnetosphere and in geomagnetic activity: 2. Response to solar wind power input and relationships with solar wind dynamic pressure and magnetospheric flux transport, Journal of Space Weather and Space Climate, 10, 30. https://doi.org/10.1051/swsc/2020033.

  3. Mike Lockwood, Mathew J Owens, Luke A Barnard, Carl Haines, Chris J Scott, Kathryn A McWilliams & John C Coxon (2020). Semi-annual, annual and Universal Time variations in the magnetosphere and in geomagnetic activity: 1. Geomagnetic data, Journal of Space Weather and Space Climate, 10, 23. https://doi.org/10.1051/swsc/2020023.

  4. Michaela K Mooney, Colin Forsyth, I Jonathan Rae, Gareth Chisham, John C Coxon, Mike S Marsh, David R Jackson, Suzy Bingham & Benoît Hubert (2020). Examining local time variations in the gains and losses of open magnetic flux during substorms, Journal of Geophysical Research: Space Physics, 125, e2019JA027369. https://doi.org/10.1029/2019JA027369.

  5. Vladimir B Ovodenko, Maxim V Klimenko, Irina E Zakharenkova, Alexey V Oinats, Daria S Kotova, Alexander V Nikolaev, Ilya V Tyutin, Denis D Rogov, Konstantin G Ratovsky, Dmitriy V Chugunin, Pavel A Budnikov, John C Coxon, Brian J Anderson & Alexander A Chernyshov (2020). Spatial and temporal evolution of different‐scale ionospheric irregularities in Central and East Siberia during the 27–28 May 2017 geomagnetic storm, Space Weather, 18, e2019SW002378. https://doi.org/10.1029/2019SW002378.

2019

  1. John C Coxon, Robert M Shore, Mervyn P Freeman, Robert C Fear, Stephen D Browett, Andrew W Smith, Daniel K Whiter & Brian J Anderson (2019). Timescales of Birkeland currents driven by the IMF, Geophysical Research Letters, 46, 7893–7901. https://doi.org/10.1029/2018GL081658.

  2. Robert C Fear, John C Coxon & Caitríona M Jackman (2019). The contribution of flux transfer events to Mercury’s Dungey cycle, Geophysical Research Letters, 46, 14239–14246. https://doi.org/10.1029/2019GL085399.

  3. Robert M Shore, Mervyn P Freeman, John C Coxon, Evan G Thomas, Jesper W Gjerloev & Nils Olsen (2019). Spatial variation in the responses of the surface external and induced magnetic field to the solar wind, Journal of Geophysical Research: Space Physics, 124, 6195–6211. https://doi.org/10.1029/2019JA026543.

  4. Lorenzo Trenchi, John C Coxon, Robert C Fear, Jonathan P Eastwood, Malcolm W Dunlop, Karlheinz J Trattner, Daniel J Gershman, Daniel B Graham, Yuri Khotyaintsev & Benoit Lavraud (2019). Signatures of magnetic separatrices at the borders of a crater flux transfer event connected to an active X‐line, Journal of Geophysical Research: Space Physics, 124, 8600–8616. https://doi.org/10.1029/2018JA026126.

2018

  1. John C Coxon, Steve E Milan & Brian J Anderson (2018). A review of Birkeland current research using AMPERE, in Electric Currents in Geospace and Beyond (eds Andreas Keiling, Octav Marghitu & Michael Wheatland). https://doi.org/10.1002/9781119324522.ch16.

  2. John C Coxon, Mervyn P Freeman, Caitríona M Jackman, Colin Forsyth, I Jonathan Rae & Robert C Fear (2018). Tailward propagation of magnetic energy density variations with respect to substorm onset times, Journal of Geophysical Research: Space Physics, 123, 4741–4754. https://doi.org/10.1029/2017JA025147.

  3. Colin Forsyth, Mark Shortt, John C Coxon, I Jonathan Rae, Mervyn P Freeman, Nadine ME Kalmoni, Caitríona M Jackman, Brian J Anderson, Steve E Milan & Angeline G Burrell (2018). Seasonal and temporal variations of field‐aligned currents and ground magnetic deflections during substorms, Journal of Geophysical Research: Space Physics, 123, 2696–2713. https://doi.org/10.1002/2017JA025136.

  4. German Farinas Perez, Flavia R Cardoso, David G Sibeck, Walter D Gonzalez, Gabor Facsko, John C Coxon & Asher D Pembroke (2018). Generation mechanism for interlinked flux tubes on the magnetopause, Journal of Geophysical Research: Space Physics, 123, 1337–1355. https://doi.org/10.1002/2017JA024664.

  5. Steve E Milan, Jennifer A Carter, Harneet Sangha, Karl M Laundal, Nikolai Østgaard, Paul Tenfjord, Jone P Reistad, Kristian Snekvik, John C Coxon, Haje Korth & Brian J Anderson (2018). Timescales of dayside and nightside field‐aligned current response to changes in solar wind‐magnetosphere coupling, Journal of Geophysical Research: Space Physics, 123, 7307–7319. https://doi.org/10.1029/2018JA025645.

  6. Andrew W Smith, Caitríona M Jackman, Christopher M Frohmaier, John C Coxon, James A Slavin & Robert C Fear (2018). Evaluating single‐spacecraft observations of planetary magnetotails with simple Monte Carlo simulations: 1. Spatial distributions of the neutral line, Journal of Geophysical Research: Space Physics, 123, 10109–10123. https://doi.org/10.1029/2018JA025958.

  7. Andrew W Smith, Caitríona M Jackman, Christopher M Frohmaier, Robert C Fear, James A Slavin, John C Coxon (2018). Evaluating single spacecraft observations of planetary magnetotails with simple Monte Carlo simulations: 2. Magnetic flux rope signature selection effects, Journal of Geophysical Research: Space Physics, 123, 10124–10138. https://doi.org/10.1029/2018JA025959.

2017

  1. John C Coxon, I Jonathan Rae, Colin Forsyth, Caitríona M Jackman, Robert C Fear & Brian J Anderson (2017). Birkeland currents during substorms: Statistical evidence for intensification of Regions 1 and 2 currents after onset and a localized signature of auroral dimming, Journal of Geophysical Research: Space Physics, 122, 6455–6468. https://doi.org/10.1002/2017JA023967.

  2. Robert C Fear, Lorenzo Trenchi, John C Coxon & Steve E Milan (2017). How much flux does a flux transfer event transfer?, Journal of Geophysical Research: Space Physics, 122, 12,310–12,327. https://doi.org/10.1002/2017JA024730.

  3. Steve E Milan, Lasse BN Clausen, John C Coxon, Jennifer A Carter, Maria-Theresia Walach, Karl M Laundal, Nikolai Østgaard, Paul Tenfjord, Jone P Reistad, Kristian Snekvik, Haje Korth & Brian J Anderson (2017). Overview of solar wind-magnetosphere-ionosphere-atmosphere coupling and the generation of magnetospheric currents, Space Science Reviews, 206, 547–573. https://doi.org/10.1007/s11214-017-0333-0.

2016

  1. John C Coxon, Caitríona M Jackman, Mervyn P Freeman, Colin Forsyth & I Jonathan Rae (2016). Identifying the magnetotail lobes with Cluster magnetometer data, Journal of Geophysical Research: Space Physics, 121, 1436–1446. https://doi.org/10.1002/2015JA022020.

  2. John C Coxon, Steve E Milan, Jennifer A Carter, Lasse BN Clausen, Brian J Anderson & Haje Korth (2016). Seasonal and diurnal variations in AMPERE observations of the Birkeland currents compared to modeled results, Journal of Geophysical Research: Space Physics, 121, 4027–4040. https://doi.org/10.1002/2015JA022050.

  3. Jennifer A Carter, Steve E Milan, John C Coxon, Maria-Theresia Walach & Brian J Anderson (2016). Average field-aligned current configuration parameterized by solar wind conditions, Journal of Geophysical Research: Space Physics, 121, 1294–1307. https://doi.org/10.1002/2015JA021567.

  4. Colin Forsyth, I Jonathan Rae, Kyle R Murphy, Mervyn P Freeman, Chia-Lin Huang, Harlan E Spence, Alexander J Boyd, John C Coxon, Caitríona M Jackman, Nadine ME Kalmoni & Clare EJ Watt (2016). What effect do substorms have on the content of the radiation belts?, Journal of Geophysical Research: Space Physics, 121, 6292–6306. https://doi.org/10.1002/2016JA022620.

  5. Karl M Laundal, Ingrid Cnossen, Steve E Milan, Stein E Haaland, John C Coxon, Nicholas M Pedatella, Matthias Förster & Jone P Reistad (2016). North–South asymmetries in Earth’s magnetic field: Effects on high-latitude geospace, Space Science Reviews, 206, 225–257. https://doi.org/10.1007/s11214-016-0273-0.

2015

  1. Colin Forsyth, I Jonathan Rae, John C Coxon, Mervyn P Freeman, Caitríona M Jackman, Jesper Gjerloev & Andrew N Fazakerley (2015). A new technique for determining Substorm Onsets and Phases from H-Indices of the Electrojet (SOPHIE), Journal of Geophysical Research: Space Physics, 120, 10,592–10,606. https://doi.org/10.1002/2015JA021343.

2014

  1. John C Coxon, Steve E Milan, Lasse BN Clausen, Brian J Anderson & Haje Korth (2014a). The magnitudes of the regions 1 and 2 Birkeland currents observed by AMPERE and their role in solar wind-magnetosphere-ionosphere coupling, Journal of Geophysical Research: Space Physics, 119, 9804–9815. https://doi.org/10.1002/2014JA020138.

  2. John C Coxon, Steve E Milan, Lasse BN Clausen, Brian J Anderson & Haje Korth (2014b). A superposed epoch analysis of the regions 1 and 2 Birkeland currents observed by AMPERE during substorms, Journal of Geophysical Research: Space Physics, 119, 9834–9846. https://doi.org/10.1002/2014JA020500.

  3. Colin Forsyth, Clare EJ Watt, I Jonathan Rae, Andrew N Fazakerley, Nadine ME Kalmoni, Mervyn P Freeman, Peter D Boakes, Rumi Nakamura, Iannis Dandouras, Lynn M Kistler, Caitríona M Jackman, John C Coxon & Chris Carr (2014). Increases in plasma sheet temperature with solar wind driving during substorm growth phases, Geophysical Research Letters, 41, 8713–8721. https://doi.org/10.1002/2014GL062400.

  4. Victor A Sergeev, Alexander V Nikolaev, Marina V Kubyshkina, Nikolai A Tsyganenko, Howard J Singer, Juan V Rodriguez, Vassilis Angelopoulos, Rumi Nakamura, Steve E Milan, John C Coxon, Brian J Anderson & Haje Korth (2014). Event study combining magnetospheric and ionospheric perspectives of the substorm current wedge modeling, Journal of Geophysical Research: Space Physics, 119, 9714–9728. https://doi.org/10.1002/2014JA020522.

2013

  1. Lasse BN Clausen, Joseph BH Baker, J Michael Ruohoniemi, Steve E Milan, John C Coxon, Simon Wing, Shin-ichi Ohtani & Brian J Anderson (2013). Temporal and spatial dynamics of the regions 1 and 2 Birkeland currents during substorms, Journal of Geophysical Research: Space Physics, 118, 3007–3016. https://doi.org/10.1002/jgra.50288.

  2. Lasse BN Clausen, Steve E Milan, Joseph BH Baker, J Michael Ruohoniemi, Karl-Heinz Glassmeier, John C Coxon & Brian J Anderson (2013). On the influence of open magnetic flux on substorm intensity: ground- and space-based observations, Journal of Geophysical Research: Space Physics, 118, 2958–2969. https://doi.org/10.1002/jgra.50308.

Thesis

Other references

  1. Matthew Allcock, Alastair Pidgeon, Gordon Black, Emily Prestwood, Alyssa Frayling, Sara Cucaro, Will Lecky, John C Coxon, Andy W Smith, Sarah N Bentley, Clare E J Watt, Robert T Wicks & I Jonathan Rae (2025). Severe Space Weather Impacts on UK Critical National Infrastructure, Starion UK Ltd, Bath, UK. https://purl.org/net/epubs/work/61075921.

  2. Michael W Liemohn, McArthur Jones Jr, Xochitl Blanco-Cano, John C Coxon, Alexa J Halford & Chigomezyo Ngwira (2023). Editorial: Driving towards a more diverse space physics research community—perspectives, initiatives, strategies, and actions, Frontiers in Astronomy and Space Sciences, 10. https://doi.org/10.3389/fspas.2023.1292058.

  3. John C Coxon, Anasuya Aruliah, Sarah N Bentley, Robert M Shore (2022). RAS Specialist Discussion Meeting report, Astronomy & Geophysics, 63(1), 30–34. https://doi.org/10.1093/astrogeo/atac011.

  4. Angeline G Burrell, McArthur Jones Jr, Alexa J Halford, Kate A Zawdie, John C Coxon (2021). Bypassing the bias, Astronomy & Geophysics, 62(5), 28–29. https://doi.org/10.1093/astrogeo/atab090.

  5. John C Coxon & Sebastien de Larquier (2020). johncoxon/tsyganenko: v2020.0.0. https://doi.org/10.5281/zenodo.3937277.

  6. John C Coxon, Jasmine Kaur Sandhu, Gabrielle Provan & James Wild (2018). Public engagement with MIST science, Astronomy & Geophysics, 59(6), 29–31. https://doi.org/10.1093/astrogeo/aty276.

  7. Jasmine Kaur Sandhu, Georgina A Graham, Sarah N Bentley & John C Coxon (2018). Autumn MIST 2017, Astronomy & Geophysics, 59(2), 26–29. https://doi.org/10.1093/astrogeo/aty090.

  8. Sarah V Badman, John C Coxon, Katie Raymer & Arianna M Sorba (2017). London MIST 2016, Astronomy & Geophysics, 58(5). 32–34. https://doi.org/10.1093/astrogeo/atx175.

  9. John C Coxon, Jasmine Kaur Sandhu, Nadine ME Kalmoni, Rebecca L Gray, Joe Kinrade & Ian McCrea (2016). Autumn MIST 2015, Astronomy & Geophysics, 57(3), 21–24. https://doi.org/10.1093/astrogeo/atw099.