Articles | Volume 5, issue 1
https://doi.org/10.5194/gi-5-253-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/gi-5-253-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
28 Jun 2016
Research article |
| 28 Jun 2016
Forecasting auroras from regional and global magnetic field measurements
Kirsti Kauristie
CORRESPONDING AUTHOR
Finnish Meteorological Institute, Helsinki, Finland
Minna Myllys
University of Helsinki, Helsinki, Finland
Noora Partamies
The University Centre in Svalbard, Svalbard, Norway
Ari Viljanen
Finnish Meteorological Institute, Helsinki, Finland
Pyry Peitso
Finnish Meteorological Institute, Helsinki, Finland
Aalto University, Espoo, Finland
Liisa Juusola
Finnish Meteorological Institute, Helsinki, Finland
Shabana Ahmadzai
University of Helsinki, Helsinki, Finland
Vikramjit Singh
Aalto University, Espoo, Finland
Ralf Keil
European Space Agency, ESOC, Darmstadt, Germany
Unai Martinez
etamax space GmbH, Darmstadt, Germany
Alexej Luginin
European Space Agency, ESOC, Darmstadt, Germany
Alexi Glover
European Space Agency, ESOC, Darmstadt, Germany
Vicente Navarro
European Space Agency, ESOC, Darmstadt, Germany
Tero Raita
Sodankylä Geophysical Observatory, University of Oulu, Oulu, Finland
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At times when auroras erupt on the sky, the magnetic field surrounding the Earth undergoes rapid changes. On the ground, these changes can induce harmful electric currents in technological conductor networks, such as powerlines. We have used magnetic field observations from northern Europe during 28 such events and found consistent behavior that can help to understand, and thus predict, the processes that drive auroras and geomagnetically induced currents.
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reset time, about 2 min. We conclude that this result gives insight on the current systems high in Earth’s atmosphere, which are the main driver behind the time derivative’s behavior and GIC formation.
Mizuki Fukizawa, Takeshi Sakanoi, Yoshimasa Tanaka, Yasunobu Ogawa, Keisuke Hosokawa, Björn Gustavsson, Kirsti Kauristie, Alexander Kozlovsky, Tero Raita, Urban Brändström, and Tima Sergienko
Ann. Geophys., 40, 475–484, https://doi.org/10.5194/angeo-40-475-2022, https://doi.org/10.5194/angeo-40-475-2022, 2022
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The pulsating auroral generation mechanism has been investigated by observing precipitating electrons using rockets or satellites. However, it is difficult for such observations to distinguish temporal changes from spatial ones. In this study, we reconstructed the horizontal 2-D distribution of precipitating electrons using only auroral images. The 3-D aurora structure was also reconstructed. We found that there were both spatial and temporal changes in the precipitating electron energy.
Sebastian Käki, Ari Viljanen, Liisa Juusola, and Kirsti Kauristie
Ann. Geophys., 40, 107–119, https://doi.org/10.5194/angeo-40-107-2022, https://doi.org/10.5194/angeo-40-107-2022, 2022
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During auroral substorms, the ionospheric electric currents change rapidly, and a large amount of energy is dissipated. We combine ionospheric current data derived from the Swarm satellite mission with the substorm database from the SuperMAG ground magnetometer network. We obtain statistics of the strength and location of the currents relative to the substorm onset. Our results show that low-earth orbit satellites give a coherent picture of the main features in the substorm current system.
Pekka T. Verronen, Antti Kero, Noora Partamies, Monika E. Szeląg, Shin-Ichiro Oyama, Yoshizumi Miyoshi, and Esa Turunen
Ann. Geophys., 39, 883–897, https://doi.org/10.5194/angeo-39-883-2021, https://doi.org/10.5194/angeo-39-883-2021, 2021
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Joshua Dreyer, Noora Partamies, Daniel Whiter, Pål G. Ellingsen, Lisa Baddeley, and Stephan C. Buchert
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Emma Bland, Fasil Tesema, and Noora Partamies
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Noora Partamies, Fasil Tesema, Emma Bland, Erkka Heino, Hilde Nesse Tyssøy, and Erlend Kallelid
Ann. Geophys., 39, 69–83, https://doi.org/10.5194/angeo-39-69-2021, https://doi.org/10.5194/angeo-39-69-2021, 2021
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during amorphous pulsating and patchy auroras.
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Ann. Geophys., 38, 557–574, https://doi.org/10.5194/angeo-38-557-2020, https://doi.org/10.5194/angeo-38-557-2020, 2020
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Coronal mass ejection sheaths and ejecta are key drivers of significant space weather storms, and they cause dramatic changes in radiation belt electron fluxes. Differences in precipitation of high-energy electrons from the belts to the upper atmosphere are thus expected. We investigate here differences in sheath- and ejecta-induced precipitation using the Finnish riometer (relative ionospheric opacity meter) chain.
Liisa Juusola, Sanni Hoilijoki, Yann Pfau-Kempf, Urs Ganse, Riku Jarvinen, Markus Battarbee, Emilia Kilpua, Lucile Turc, and Minna Palmroth
Ann. Geophys., 36, 1183–1199, https://doi.org/10.5194/angeo-36-1183-2018, https://doi.org/10.5194/angeo-36-1183-2018, 2018
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The solar wind interacts with the Earth’s magnetic field, forming a magnetosphere. On the night side solar wind stretches the magnetosphere into a long tail. A process called magnetic reconnection opens the magnetic field lines and reconnects them, accelerating particles to high energies. We study this in the magnetotail using a numerical simulation model of the Earth’s magnetosphere. We study the motion of the points where field lines reconnect and the fast flows driven by this process.
Liisa Juusola, Yann Pfau-Kempf, Urs Ganse, Markus Battarbee, Thiago Brito, Maxime Grandin, Lucile Turc, and Minna Palmroth
Ann. Geophys., 36, 1027–1035, https://doi.org/10.5194/angeo-36-1027-2018, https://doi.org/10.5194/angeo-36-1027-2018, 2018
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The Earth's magnetic field is shaped by the solar wind. On the dayside the field is compressed and on the nightside it is stretched as a long tail. The tail has been observed to occasionally undergo flapping motions, but the origin of these motions is not understood. We study the flapping using a numerical simulation of the near-Earth space. We present a possible explanation for how the flapping could be initiated by a passing disturbance and then maintained as a standing wave.
Minna Palmroth, Sanni Hoilijoki, Liisa Juusola, Tuija I. Pulkkinen, Heli Hietala, Yann Pfau-Kempf, Urs Ganse, Sebastian von Alfthan, Rami Vainio, and Michael Hesse
Ann. Geophys., 35, 1269–1274, https://doi.org/10.5194/angeo-35-1269-2017, https://doi.org/10.5194/angeo-35-1269-2017, 2017
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Much like solar flares, substorms occurring within the Earth's magnetic domain are explosive events that cause vivid auroral displays. A decades-long debate exists to explain the substorm onset. We devise a simulation encompassing the entire near-Earth space and demonstrate that detailed modelling of magnetic reconnection explains the central substorm observations. Our results help to understand the unpredictable substorm process, which will significantly improve space weather forecasts.
Noora Partamies, James M. Weygand, and Liisa Juusola
Ann. Geophys., 35, 1069–1083, https://doi.org/10.5194/angeo-35-1069-2017, https://doi.org/10.5194/angeo-35-1069-2017, 2017
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Large-scale undulations of the diffuse aurora boundary, auroral omega bands, have been studied based on 438 omega-like structures identified over Fennoscandian Lapland from 1996 to 2007. The omegas mainly occurred in the post-magnetic midnight sector, in the region between oppositely directed ionospheric field-aligned currents, and during substorm recovery phases. The omega bands were observed during substorms, which were more intense than the average substorm in the same region.
Fred Sigernes, Pål Gunnar Ellingsen, Noora Partamies, Mikko Syrjäsuo, Pål Brekke, Silje Eriksen Holmen, Arne Danielsen, Bernt Olsen, Xiangcai Chen, Margit Dyrland, Lisa Baddeley, Dag Arne Lorentzen, Marcus Aleksander Krogtoft, Torstein Dragland, Hans Mortensson, Lisbeth Smistad, Craig J. Heinselman, and Shadia Habbal
Geosci. Instrum. Method. Data Syst., 6, 9–14, https://doi.org/10.5194/gi-6-9-2017, https://doi.org/10.5194/gi-6-9-2017, 2017
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The total solar eclipse event on Svalbard on 20 March 2015 gave us a unique opportunity to image the upper parts of the Sun's atmosphere. A novel image accumulation filter technique is presented that is capable of distinguishing features such as loops, spicules, plumes, and prominences from intense and blurry video recordings of the chromosphere.
Yann Pfau-Kempf, Heli Hietala, Steve E. Milan, Liisa Juusola, Sanni Hoilijoki, Urs Ganse, Sebastian von Alfthan, and Minna Palmroth
Ann. Geophys., 34, 943–959, https://doi.org/10.5194/angeo-34-943-2016, https://doi.org/10.5194/angeo-34-943-2016, 2016
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We have simulated the interaction of the solar wind – the charged particles and magnetic fields emitted by the Sun into space – with the magnetic field of the Earth. The solar wind flows supersonically and creates a shock when it encounters the obstacle formed by the geomagnetic field. We have identified a new chain of events which causes phenomena in the downstream region to eventually cause perturbations at the shock and even upstream. This is confirmed by ground and satellite observations.
Tuomas Savolainen, Daniel Keith Whiter, and Noora Partamies
Geosci. Instrum. Method. Data Syst., 5, 305–314, https://doi.org/10.5194/gi-5-305-2016, https://doi.org/10.5194/gi-5-305-2016, 2016
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In this paper we describe a new method for recognition of digits in seven-segment displays. The method is used for adding date and time information to a dataset consisting of about 7 million auroral all-sky images taken during the time period of 1973–1997 at camera stations centred around Sodankylä observatory in Northern Finland. In each image there is a clock display for the date and time together with the reflection of the whole night sky through a spherical mirror.
Johannes Norberg, Lassi Roininen, Antti Kero, Tero Raita, Thomas Ulich, Markku Markkanen, Liisa Juusola, and Kirsti Kauristie
Geosci. Instrum. Method. Data Syst., 5, 263–270, https://doi.org/10.5194/gi-5-263-2016, https://doi.org/10.5194/gi-5-263-2016, 2016
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The Sodankylä Geophysical Observatory has been producing ionospheric tomography data since 2003. Based on these data, one solar cycle of ionospheric vertical total electron content (VTEC) estimates is constructed. The measurements are compared against the IRI-2012 model, F10.7 solar flux index and sunspot number data. Qualitatively the tomographic VTEC estimate corresponds to reference data very well, but the IRI-2012 model are on average 40 % higher of that of the tomographic results.
Peter Wintoft, Ari Viljanen, and Magnus Wik
Ann. Geophys., 34, 485–491, https://doi.org/10.5194/angeo-34-485-2016, https://doi.org/10.5194/angeo-34-485-2016, 2016
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Extreme value analysis has been applied to 1-minute-resolution magnetic fields and computed electric fields over Europe. We find that on average the largest disturbances of the fields are observed close to the auroral oval, as expected. However, the analysis indicates that as we move south from Scandinavia to northern continental Europe the distribution becomes more extreme. This could be due to that strong storms regularly occur at high latitudes, while the extreme storms push the oval south.
Johannes Norberg, Ilkka I. Virtanen, Lassi Roininen, Juha Vierinen, Mikko Orispää, Kirsti Kauristie, and Markku S. Lehtinen
Atmos. Meas. Tech., 9, 1859–1869, https://doi.org/10.5194/amt-9-1859-2016, https://doi.org/10.5194/amt-9-1859-2016, 2016
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We validate 2-D ionospheric tomography reconstructions against EISCAT incoherent scatter radar measurements. The method is based on Bayesian statistical inversion. We employ ionosonde measurements for the choice of the prior distribution parameters and use a sparse matrix approximation for the computations. This results in a computationally efficient tomography algorithm with clear probabilistic interpretation. We find that ionosonde measurements improve the reconstruction significantly.
K. Kauristie, M. V. Uspensky, N. G. Kleimenova, O. V. Kozyreva, M. M. J. L. Van De Kamp, S. V. Dubyagin, and S. Massetti
Ann. Geophys., 34, 379–392, https://doi.org/10.5194/angeo-34-379-2016, https://doi.org/10.5194/angeo-34-379-2016, 2016
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This study presents some example events in which sudden changes in the auroral activity at midnight sector seem to have an impact on the intensity of morning-sector magnetic pulsations. Mechanisms which could link these two separate regions are discussed in the paper. Sudden changes in the solar wind properties and fast westward-propagating electrons are suggested to explain the coupling between midnight-sector and morning-sector phenomena.
M. Myllys, E. Kilpua, and T. Pulkkinen
Ann. Geophys., 33, 845–855, https://doi.org/10.5194/angeo-33-845-2015, https://doi.org/10.5194/angeo-33-845-2015, 2015
M. Myllys, N. Partamies, and L. Juusola
Ann. Geophys., 33, 573–581, https://doi.org/10.5194/angeo-33-573-2015, https://doi.org/10.5194/angeo-33-573-2015, 2015
P. T. Verronen, M. E. Andersson, A. Kero, C.-F. Enell, J. M. Wissing, E. R. Talaat, K. Kauristie, M. Palmroth, T. E. Sarris, and E. Armandillo
Ann. Geophys., 33, 381–394, https://doi.org/10.5194/angeo-33-381-2015, https://doi.org/10.5194/angeo-33-381-2015, 2015
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Electron concentrations observed by EISCAT radars can be reasonable well represented using AIMOS v1.2 satellite-data-based ionization model and SIC D-region ion chemistry model. SIC-EISCAT difference varies from event to event, probably because the statistical nature of AIMOS ionization is not capturing all the spatio-temporal fine structure of electron precipitation. Below 90km, AIMOS overestimates electron ionization because of proton contamination of the satellite electron detectors.
M. van de Kamp, D. Pokhotelov, and K. Kauristie
Ann. Geophys., 32, 1511–1532, https://doi.org/10.5194/angeo-32-1511-2014, https://doi.org/10.5194/angeo-32-1511-2014, 2014
K. Andréeová, L. Juusola, E. K. J. Kilpua, and H. E. J. Koskinen
Ann. Geophys., 32, 1293–1302, https://doi.org/10.5194/angeo-32-1293-2014, https://doi.org/10.5194/angeo-32-1293-2014, 2014
B. J. Jackel, C. Unick, M. T. Syrjäsuo, N. Partamies, J. A. Wild, E. E. Woodfield, I. McWhirter, E. Kendall, and E. Spanswick
Geosci. Instrum. Method. Data Syst., 3, 71–94, https://doi.org/10.5194/gi-3-71-2014, https://doi.org/10.5194/gi-3-71-2014, 2014
D. K. Whiter, B. Gustavsson, N. Partamies, and L. Sangalli
Geosci. Instrum. Method. Data Syst., 2, 131–144, https://doi.org/10.5194/gi-2-131-2013, https://doi.org/10.5194/gi-2-131-2013, 2013
N. Partamies, L. Juusola, E. Tanskanen, and K. Kauristie
Ann. Geophys., 31, 349–358, https://doi.org/10.5194/angeo-31-349-2013, https://doi.org/10.5194/angeo-31-349-2013, 2013
Related subject area
Data archive
Weather model verification using Sodankylä mast measurements
Markku Kangas, Laura Rontu, Carl Fortelius, Mika Aurela, and Antti Poikonen
Geosci. Instrum. Method. Data Syst., 5, 75–84, https://doi.org/10.5194/gi-5-75-2016, https://doi.org/10.5194/gi-5-75-2016, 2016
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Sodankylä, in the heart of the Arctic Research Centre of the Finnish Meteorological Institute in northern Finland with temperatures ranging from −50 to +30 °C, provides a challenging location for numerical weather forecasting (NWP) models. In this article, the use of measurements performed in Sodankylä for near-real time online verification of NWP models is described. A more specific case study of three different radiation schemes, applicable in NWP model HARMONIE-AROME, is also presented.
Cited articles
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Short summary
We use the connection between auroras and geomagnetic field variations in a concept for a Regional Auroral Forecast (RAF) service. RAF is based on statistical relationships between alerts by the NOAA Space Weather Prediction Center and magnetic time derivatives measured by five MIRACLE magnetometer stations located in the surroundings of the Sodankylä research station. As an improvement to previous similar services RAF yields knowledge on typical auroral storm durations at different latitudes.
We use the connection between auroras and geomagnetic field variations in a concept for a...
