Curator: James Weygand
Institute of Geophysics and Planetary Physics, UCLA
Phone: (310) 825-3547
E-mail: jweygand(at)igpp.ucla.edu
News:
Matlab programs are available to combine the spherical elementary currents with vertical total electron content measurements, SuperDARN flows, THEMIS all sky images, and AMPERE data.
Data Access
Contact James Weygand. E-mail above.
Validated data can be found at the Virtual Magnetospheric Observatory: Equivalent Currents, Current Amplitudes, and Quicklook plots. Data not yet at the VMO has not been validated and is available upon request.
Key References:
•Amm, O., and A. Viljanen, Ionospheric disturbance magnetic field continuation from the ground to the ionosphere using spherical elementary current systems, Earth Planets Space, 51,431-440, 1999.
•Weygand et al., Application and Validation of the Spherical Elementary Currents Systems Technique for Deriving Ionospheric Equivalent Currents with the North American and Greenland Ground Magnetometer Arrays, J. Geophys. Res., 115 doi:10.1029/2010JA016177, 2011.
The Code:
The original Matlab code was provide by Dr. Olaf Amm [Amm and Viljanen, 1999]. James Weygand has adapted the code to include ground magnetometer data from AUTUMNX, CANMOS, CARISMA, Falcon, GIMA, Greenland, MACCS, STEP, USGS, McMAC, and THEMIS.
The Data
Inputs: Nearly all the data was obtained from: AUTUMNX, CANMOS, CARISMA, GIMA, DTU (Greenland), MACCS, McMAC, THEMIS, STEP, and USGS. Some data was obtained directly from the PIs.
Outputs: Equivalent ionospheric currents over most parts of Canada, Alaska, until the Greenland coast (roughly corresponding to an area of about 40 degrees latitude and 120 degrees longitude)”
Equivalent Ionospheric Current Data Availability
| Arrays Involved | Interval (YYYY/MM/DD to YYYY/MM/DD) |
| AUTUMNX, CANMOS, CARISMA, GIMA, DTU, McMac, MACCS, THEMIS, USGS, AUTUMN, and STEP |
2007/01/01 to 2020/11/30 |
Example Event
| Equivalent Ionospheric Currents |
 |
| Scaling factors of spherical elementary currents systems (proportional to FAC for uniform conductances) |
 |
Acknowledgments
CANMOS and CARISMA: These data were obtained from the Canadaian Space Science Data Portal.
The Canadian Space Science Data Portal is funded in part by the Canadian Space Agency (CSA), the Alberta Science and Research Authority (ASRA), and the University of Alberta (UofA).
Also see CARISMA rules of the road.
CANMOS data were obtained by the Canadian Magnetic Observatory Network (CANMON), maintained and operated by the Geological Survey of Canada, provided the data used in this study – http://gsc.nrcan.gc.ca/geomag.
GIMA: acknowledge the Geophysical Institute, University of Alaska Fairbanks.
Greenland: acknowledge the Technical University of Denmark (DTU).
MACCS: Magnetometer Array for Cusp and Cleft Studies (MACCS) array is
supported by US National Science Foundation grant ATM-0827903 to Augsburg College.
We would like to would like to thank the following:
M. J. Engebretson, D. Murr, and E.S. Steinmetz at Augsburg College and the MACCS team.
THEMIS: see THEMIS rules of the road.
STEP: STEP magnetometer file storage is at Department of Earth and Planetary Physics,
The University of Tokyo and maintained by Dr. Kanji Hayashi (hayashi.AT.grl.s.u-tokyo.ac.jp)
McMAC: The McMAC Project is sponsored by the Magnetospheric Physics Program of
National Science Foundation and maintained by Dr. Peter Chi (pchi AT igpp.ucla.edu)
USGS: The USGS Geomagnetism Program
Publications:
•Keiling, A., V. Angelopoulos, A. Runov, J. Weygand, S.V. Apatenkov, S. Mende, J. McFadden, D. Larson, O. Amm, K.-H. Glassmeier, and H.U. Auster, Substorm current wedge driven by plasma flow vortices: THEMIS observations, J. Geophys. Res., 114, A00C22, doi:10.1029/2009JA014114, 2009.
•Frey, H.U., O. Amm, C.C. Chaston, S. Fu, G. Haerendel, L. Juusola, T. Karlsson, B. Lanchester, R. Nakamura, N. Ostgaard, T. Sakanoi, E. Seran , D. Whiter, J. Weygand, K. Asamura, and M. Hirahara, Small and meso-scale properties of a substorm onset auroral arc, J. Geophys. Res., 115, A10209, doi:10.1029/ 2010JA015537, 2010.
•Weygand et al., Application and Validation of the Spherical Elementary Currents Systems Technique for Deriving Ionospheric Equivalent Currents with the North American and Greenland Ground Magnetometer Arrays, J. Geophys. Res.,
115 doi:10.1029/2010JA016177, 2011.
•Keiling, A., V. Angelopoulos, J.M. Weygand, O. Amm, E. Spanswick, E. Donovan, S. Mende, J. McFadden, D. Larson, K.-H. Glassmeier, and H.U. Auster, THEMIS ground-space observations during the development of auroral spirals, Ann. Geophys., 27, 4317-4332, 2009.
•Nakamura, R. W. Baumjohann, E. Panov, A. A. Petrukovich, V. Angelopoulos, M. Volwerk, W. Magnes, Y. Nishimura, A. Runov,
C.T. Russell, J.M. Weygand, O. Amm, H.-U. Auster, J. Bonnell, H. Frey, D. Larson, and J. McFadden, Flux transport, dipolarization and current sheet evolution during a doubleonset substorm, J. Geophys. Res., 116, A00136, doi:10.1029/2010JA015865, 2011.
•Partamies, N., L. Juusola, E. Tanskanen, K. Kauristie, and J.M. Weygand, Substorms during different storm phases, Ann. Geophys., 29, 2031-2043, 2011.
•Yang, J., F. Toffoletto, R. Wolf, S. Sazykin, P. Ontiveros, and J.M. Weygand, Large-scale current systems and ground magnetic disturbance during deep substorm injections, J. Geophys. Res., 117, A4, doi:10.1029/2011JA017415, 2012.
•Jiang, F., R.J. Strangeway, M.G. Kivelson, J.M. Weygand, R.J. Walker, K.K. Khurana, Y. Nishimura, V. Angelopoulos, E. Donovan, In-situ observations of the preexisting auroral arc by THEMIS All Sky Imagers and the FAST spacecraft, J. Geophys. Res., 117, A05211, doi:10.1029/ 2011JA017128, 2011.
•Weygand, J.M., O. Amm, V. Angelopoulos, S.E. Milan, A. Grocott, H. Gleisner, C. Stolle, Comparison Between SuperDARN Flow Vectors and Equivalent Ionospheric Currents from Ground Magnetometer Arrays, J. Geophys. Res., 117, A05325, doi:10.1029/2011JA017407, 2012.
•Haerendel, G., H. U. Frey, C. C. Chaston, O. Amm, L. Juusola, R. Nakamura, E. Seran, and J.M. Weygand, Birth and Life of Auroral Arcs Embedded in the Evening Auroral Oval Convection: A Critical Comparison of Observations with Theory, J. Geophys. Res., 117, A12220, doi:10.1029/2012JA018128, 2012.
•Nakamura, R., W. Baumjohann, E. Panov, M. Volwerk, J. Birn, A. Artemyev, A.A. Petrukovich, O. Amm, L. Juusola, M.G. Kubyshkina, V.A. Sergeev, S. Apatenkov, E. Kronberg, P. Daly, A. Fazakerley, Y. Khotyaintsev, M. Fillingim, J. M. Weygand, Flow bouncing and electron injection observed by Cluster, J. Geophys. Res., 118, 2055-2072, doi:10.1002/jgra.50134, 2013.
•Shi, Q., M. Hartinger, V. Angelopoulos, Q.-G. Zong, X.-Z. Zhou, X. Zhou, A. Kellerman, A. Tian, J.M. Weygand, S. Fu, Zuyin Pu, J. Raeder, Y. Ge, Y. Wang, H. Zhang, Z. Yao, THEMIS observations of ULF wave excitation in the nightside plasma sheet during sudden impulse events, J. Geophys. Res., 118, 284-298, doi:10.1029/2012JA017984, 2012.
•Archer, M. O., T. S. Horbury, J. P. Eastwood, J. M. Weygand, and T. K. Yeoman, Magnetospheric response to magnetosheath pressure pulses: A low-pass filter effect, J. Geophys. Res., 118, doi:10.1002/jgra.50519, 2013.
•Panov E. V., W. Baumjohann, R. Nakamura, O. Amm, M. V. Kubyshkina, K.-H. Glassmeier, J. M. Weygand, V. Angelopoulos, A. A. Petrukovich, and V. A. Sergeev, Ionospheric response to oscillatory flow braking in the magnetotail, J. Geophys. Res., 118, 1529-1544, doi:10.1002/jgra.50190, 2013.
•Amosova, M. O. Amm, J. Norberg, J. Semeter, J.M. Weygand, Electron density spatial correlation at F-layer: Preliminary results from PFISR, XXVI Geofysiikan Päivät, edited by T. Veikkolainen, K. Suhonen, J. Näränen, T. Korja, K. Kauristie, and S. Kaasalainen, Geophysical Society of Finland, 19-22, 2013.
•Shi,Q.Q., M.D. Hartinger, V. Angelopoulos, A.M. Tian, S.Y. Fu, Q.-G. Zong, J.M. Weygand, J. Raeder, Z.Y. Pu, X.Z. Zhou, M.W. Dunlop, W.L. Liu, H. Zhang, Z.H. Yao, and X.C. Shen, Solar wind pressure pulse-driven magnetospheric vortices and their global consequences, J. Geophys. Res., 119, 4274-4280, doi:10.1002/2013JA019551, 2014.
•Zhao, H.Y., X.C. Shen, B.B. Tang, A.M. Tian, Q.Q. Shi, J.M. Weygand, Z.H. Yao, Q.-G. Zong, S.Y. Fu, S.T. Yao,
T. Xiao, and Z.Y. Pu, Magnetospheric vortices and their global effect after a solar wind dynamic pressure decrease, J. Geophys. Res., 120,doi:10.1002/2015JA021646, 2015.
•Weygand, J.M., M.G. Kivelson, V. Angelopoulos, H.U. Frey, J.V. Rodriguez, R. Redmon, J. Barker-Tvedtnes, A. Grocott, O. Amm, and X. Xing, An interpretation of spacecraft and ground based observations of multiple omega bands events, JASTP, 133, 185-204, 2015.
•Weygand, J.M., and S. Wing, Comparison of DMSP and SECS region-1 and region-2 ionospheric current boundary, JASTP, 143, 8-13, 2016.
•Panov, E., W. Baumjohann, R. Wolf, R. Nakamura, V. Angelopoulos, J.M. Weygand, and M. Kubyshkina, Magnetotail energy dissipation during an auroral substorm, Nature Physics, 2016.
•Lyons, L.R., B. Gallardo-Lacourt, S. Zou, J.M. Weygand, Y. Nishimura, W. Li, M. Gkioulidou, V. Angelopoulos, E.F. Donovan, J.M. Ruohoniemi, N. Nishitani, The March 17, 2013 Storm: Synergy of observation related to electric field modes and their ionospheric and magnetospheric effects, J. Geophys. Res., 121, doi:10.1002/2016JA023237, 2016.
•Carter, B.A., E. Yizengaw, R. Pradipta, J.M. Weygand, M. Piersant, A. Pulkkinen, M. Moldwin, R. Norman, and K. Zhang Geomagnetically inducaed currents around the world during 2015 St. Patrick’s day storm, submitted to J. Geophys. Res., 121, doi:10.1002/2016JA023344, 2016.
•Prikryl, P. R. Ghoddousi-Fard, M. Connors, J.M. Weygand, A. Viljanen, D.W. Danskin, T. Jayachandran, K.S Jacobson, Y.L. Andalsvik, E.G. Thomas, J.M. Rouhoiemi, T. Durgonics, K. Oksavik, Y. Zhang, E Spanswik, M. Aquino, and V. Sreeja, GPS phase scintillation at high -latitudes during the geomagnetic storm of March 17-18, 2015, J. Geophys. Res., 121, doi:10.1002/2016JA023171, 2016.
•Prikryl, P., R. Ghoddousi-Fard, A. Viljanen, J.M. Weygand, B.S.R. Kunduri, E.G. Thomas, J.M. Ruohoniemi, M. Connors, D.W. Danskin, P.T. Jayachandran, K.S. Jacobsen, Y.L. Andalsvik, T. Durgonics, K. Oksavik, Y. Zhang, E. Spanswick, M. V. Sreeja, M. Aquino, P.J. Cilliers, G. Li, B. Ning, C.N. Mitchell, L. Spogli, M. Terkildsen, A.T. Weatherwax, GPS phase scintillation and auroral electrojet currents during geomagnetic storms of March 17, 2013 and 2015, XXXII International Union of Radio Science General Essembly and Scientific Symposium proceedings, 2017.
•Ngwira C. M., Sibeck, D., Silveira, M. D. V., Georgiou, M., Weygand, J. M., Nishimura, Y., and D. Hampton, A study of intense local dB?dt variations during two geomagnetic storms. Space Weather, 16, 676–693. https://doi.org/10.1029/2018SW001911, 2018. •Angelopoulos, V., et al., The Space Physics Environment Data Analysis System (SPEDAS), subbmitted. 2018.
•Zhao, H., X.Z. Zhou, Q.G. Zong, J.M. Weygand, Q. Shi, Y. Liu, Z. Yao, Y. Wang, X.-C. Shen, J. Ren, H. Liu, and A. Tian, Small-Scale Aurora Associated With Magnetospheric Flow Vortices After a Solar Wind Dynamic Pressure Decrease. Journal of Geophysical Research Space Physics, 124(5), 3303-3311, 2019.
•Engebretson, M.J., V.A. Pilipenko, L.Y. Ahmed, J.L. Posch, E.S. Steinmetz, M.B. Moldwin, M. G. Connors, J.M. Weygand, I.R. Mann, D.H. Boteler, C.T. Russell, and A.V. Vorobev, Nighttime magnetic perturbation events observed in Arctic Canada: 1. Survey and statistical analysis. Journal of Geophysical Research: Space Physics, 124(9), 7442-7458, 2019.
•Engebretson, M.J., E.S. Steinmetz, J.L. Posch, V.A. Pilipenko, M.B. Moldwin, M.G. Connors, D.H. Boteler, I.R. Mann, M.D. Hartinger, J.M. Weygand, L.R. Lyons, Y. Nishimura, H.J. Singer, S. Ohtani, C.T. Russell, A. Fazakerley, and L.M. Kistler, Nighttime magnetic perturbation events observed in Arctic Canada: 2. Multiple-instrument observations, Journal of Geophysical Research: Space Physics, 124(9), 7459-7476, 2019.
•Panov, E.V., W. Baumjohann, R. Nakamura, J.M. Weygand, B.L. Giles, C.T. Russell, G. Reeves M.V. Kubyshkina, Continent- Wide R1/R2 Current System and Ohmic Losses by Broad Dipolarization-Injection Fronts. Journal of Geophysical Research: Space Physics, 124(6), 4064-4082, 2019.
•Weygand, J.M. and S. Wing, Temporal and Spatial Development of TEC Enhancements during Substorms, Journal of Geophysical Research: Space Physics, doi:10.1029/2019JA026985, 2020.
•Nishimura, Y., L.R. Lyons, C. Gabrielse, N. Sivadas, E.F. Donovan, R.H. Varney, V. Angelopoulos, J.M. Weygand, M.G. Conde, and R. Zhang, Extreme magnetosphere-ionosphere thermosphere responses to the 5 April 2010 super substorm. Journal of Geophysical Research: Space Physics, doi:10.1029/2019JA027654, 2020.
•Nishimura, T., J. Yang, J.M. Weygand, W. Wang, B. Kosar, E F. Donovan, V. Angelopoulos, L. Paxton, and N. Nishitani, Magnetospheric conditions for STEVE and SAID: Particle injection, substorm surge and field-aligned currents, submitted to the Journal of Geophysical Research – Space Physics, 2020, e2020JA027782.
•Nishimura, T., L.R. Lyons, C. Gabrielse, J.M. Weygand, E. F. Donovan, and V. Angelopoulos, Dawn-dusk scale size of the substorm current wedge: Large-scale vs. localized multiple wedges, Earth, Planets and Space, 72(1), 1-10, 2020.
•Chu, X., R.L. McPherron, T.-S. Hsu, V. Angelopoulos, J.M. Weygand, J. Liu, and J. Bortnik, Magnetotail flux accumulation leads to substorm current wedge: a case study, Journal of Geophysical Research – Space Physics, e2020JA028342, 2020.
•Prikryl, P., J.M. Weygand, R. Ghoddousi-Fard, P.T. Jayachandran, D.R Themens, A.M. McCaffrey, B.S.R. Kunduri, and L. Nikitina, Temporal and spatial variations of GPS TEC and phase during auroral substorms and breakups, submitted to Polar Science, 2020.