Articles | Volume 3, issue 1
https://doi.org/10.5194/gi-3-71-2014
© Author(s) 2014. 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-3-71-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Auroral spectral estimation with wide-band color mosaic CCDs
B. J. Jackel
Physics and Astronomy Department, University of Calgary, Calgary, Canada
C. Unick
Physics and Astronomy Department, University of Calgary, Calgary, Canada
M. T. Syrjäsuo
School of Electrical Engineering, Aalto University, Espoo, Finland
N. Partamies
Finnish Meteorological Institute, Helsinki, Finland
J. A. Wild
Department of Physics, Lancaster University, Lancaster, UK
E. E. Woodfield
British Antarctic Survey, Cambridge, UK
I. McWhirter
Department of Physics and Astronomy, University College London, London, UK
E. Kendall
SRI International, Menlo Park, California, USA
E. Spanswick
Physics and Astronomy Department, University of Calgary, Calgary, Canada
Related authors
Brian J. Jackel, Craig Unick, Fokke Creutzberg, Greg Baker, Eric Davis, Eric F. Donovan, Martin Connors, Cody Wilson, Jarrett Little, M. Greffen, and Neil McGuffin
Geosci. Instrum. Method. Data Syst., 5, 493–512, https://doi.org/10.5194/gi-5-493-2016, https://doi.org/10.5194/gi-5-493-2016, 2016
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In order to compare auroral observations, it is necessary to ensure that all instruments are properly calibrated. This can be difficult to achieve with different instruments operated for extended intervals at remote field sites under harsh conditions. Astronomical sources can be used for independent absolute calibration procedures. Under ideal conditions Jupiter is an excellent source, as it can provide more light than the brightest star. We use Jupiter to calibrate an auroral MSP network.
Maxime Grandin, Noora Partamies, and Ilkka I. Virtanen
Ann. Geophys., 42, 355–369, https://doi.org/10.5194/angeo-42-355-2024, https://doi.org/10.5194/angeo-42-355-2024, 2024
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Auroral displays typically take place at high latitudes, but the exact latitude where the auroral breakup occurs can vary. In this study, we compare the characteristics of the fluxes of precipitating electrons from space during auroral breakups occurring above Tromsø (central part of the auroral zone) and above Svalbard (poleward boundary of the auroral zone). We find that electrons responsible for the aurora above Tromsø carry more energy than those precipitating above Svalbard.
Maxime Grandin, Emma Bruus, Vincent E. Ledvina, Noora Partamies, Mathieu Barthelemy, Carlos Martinis, Rowan Dayton-Oxland, Bea Gallardo-Lacourt, Yukitoshi Nishimura, Katie Herlingshaw, Neethal Thomas, Eero Karvinen, Donna Lach, Marjan Spijkers, and Calle Bergstrand
EGUsphere, https://doi.org/10.5194/egusphere-2024-2174, https://doi.org/10.5194/egusphere-2024-2174, 2024
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We carried out a citizen science study of aurora sightings and experienced technological disruptions during the extreme geomagnetic storm of 10 May 2024. We collected reports from 696 observers from over 30 countries via an online survey, supplemented with observations logged in the Skywarden database. We found that the aurora was seen from exceptionally low latitudes and had very bright red and pink hues, suggesting that high fluxes of low-energy electrons from space entered the atmosphere.
Noora Partamies, Bas Dol, Vincent Teissier, Liisa Juusola, Mikko Syrjäsuo, and Hjalmar Mulders
Ann. Geophys., 42, 103–115, https://doi.org/10.5194/angeo-42-103-2024, https://doi.org/10.5194/angeo-42-103-2024, 2024
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Auroral imaging produces large amounts of image data that can no longer be analyzed by visual inspection. Thus, every step towards automatic analysis tools is crucial. Previously supervised learning methods have been used in auroral physics, with a human expert providing ground truth. However, this ground truth is debatable. We present an unsupervised learning method, which shows promising results in detecting auroral breakups in the all-sky image data.
Noora Partamies, Daniel Whiter, Kirsti Kauristie, and Stefano Massetti
Ann. Geophys., 40, 605–618, https://doi.org/10.5194/angeo-40-605-2022, https://doi.org/10.5194/angeo-40-605-2022, 2022
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We investigate the local time behaviour of auroral structures and emission height. Data are collected from the Fennoscandian Lapland and Svalbard latitutes from 7 identical auroral all-sky cameras over about 1 solar cycle. The typical peak emission height of the green aurora varies from 110 km on the nightside to about 118 km in the morning over Lapland but stays systematically higher over Svalbard. During fast solar wind, nightside emission heights are 5 km lower than during slow solar wind.
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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This paper is the first to simulate and analyse the pulsating aurorae impact on middle atmosphere on monthly/seasonal timescales. We find that pulsating aurorae have the potential to make a considerable contribution to the total energetic particle forcing and increase the impact on upper stratospheric odd nitrogen and ozone in the polar regions. Thus, it should be considered in atmospheric and climate simulations.
Joshua Dreyer, Noora Partamies, Daniel Whiter, Pål G. Ellingsen, Lisa Baddeley, and Stephan C. Buchert
Ann. Geophys., 39, 277–288, https://doi.org/10.5194/angeo-39-277-2021, https://doi.org/10.5194/angeo-39-277-2021, 2021
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Small-scale auroral features are still being discovered and are not well understood. Where aurorae are caused by particle precipitation, the newly reported fragmented aurora-like emissions (FAEs) seem to be locally generated in the ionosphere (hence,
aurora-like). We analyse data from multiple instruments located near Longyearbyen to derive their main characteristics. They seem to occur as two types in a narrow altitude region (individually or in regularly spaced groups).
Emma Bland, Fasil Tesema, and Noora Partamies
Ann. Geophys., 39, 135–149, https://doi.org/10.5194/angeo-39-135-2021, https://doi.org/10.5194/angeo-39-135-2021, 2021
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A total of 10 Super Dual Auroral Radar Network radars were used to estimate the horizontal area over which energetic electrons impact the atmosphere at 70–100 km altitude during pulsating aurorae (PsAs). The impact area varies significantly from event to event. Approximately one-third extend over 12° of magnetic latitude, while others are highly localised. Our results could be used to improve the forcing used in atmospheric/climate models to properly capture the energy contribution from PsAs.
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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About 200 nights of substorm activity have been analysed for their magnetic disturbance magnitude and the level of cosmic radio noise absorption. We show that substorms with a single expansion phase have limited lifetimes and spatial extents. Starting from magnetically quiet conditions, the strongest absorption occurs after 1 to 2 nights of substorm activity. This prolonged activity is thus required to accelerate particles to energies, which may affect the atmospheric chemistry.
Fasil Tesema, Noora Partamies, Hilde Nesse Tyssøy, and Derek McKay
Ann. Geophys., 38, 1191–1202, https://doi.org/10.5194/angeo-38-1191-2020, https://doi.org/10.5194/angeo-38-1191-2020, 2020
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In this study, we present the ionization level from EISCAT radar experiments and cosmic noise absorption level
from KAIRA riometer observations during pulsating auroras. We found thick layers of ionization that reach down
to 70 km (harder precipitation) and higher cosmic noise absorption during patchy pulsating aurora than
during amorphous pulsating and patchy auroras.
Anasuya Aruliah, Matthias Förster, Rosie Hood, Ian McWhirter, and Eelco Doornbos
Ann. Geophys., 37, 1095–1120, https://doi.org/10.5194/angeo-37-1095-2019, https://doi.org/10.5194/angeo-37-1095-2019, 2019
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Winds near the top of the atmosphere are expected to be the same at all heights for a given location by assuming high viscosity in rarefied gases. However, wind measurements from satellite drag at 350–400 km altitude were found to be up to 2 times larger than optical measurements at ∼240 km. Satellites provide global measurements, and ground-based FPIs provide long-term monitoring at single sites. So we must understand this inconsistency to model and predict atmospheric behaviour correctly.
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.
Bing Yang, Eric Donovan, Jun Liang, and Emma Spanswick
Ann. Geophys., 35, 217–225, https://doi.org/10.5194/angeo-35-217-2017, https://doi.org/10.5194/angeo-35-217-2017, 2017
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This is the first statistical study of the motion of patchy pulsating aurora (PPA). Our results show that PPA patches mainly drift eastward after midnight and westward before midnight, which suggests that the drifts of auroral patches could be a proxy for the ionospheric convection and provide a convenient and accurate method to remotely sense the magnetospheric convection. We also found that patch velocities do not seem to depend on AE index.
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.
Brian J. Jackel, Craig Unick, Fokke Creutzberg, Greg Baker, Eric Davis, Eric F. Donovan, Martin Connors, Cody Wilson, Jarrett Little, M. Greffen, and Neil McGuffin
Geosci. Instrum. Method. Data Syst., 5, 493–512, https://doi.org/10.5194/gi-5-493-2016, https://doi.org/10.5194/gi-5-493-2016, 2016
Short summary
Short summary
In order to compare auroral observations, it is necessary to ensure that all instruments are properly calibrated. This can be difficult to achieve with different instruments operated for extended intervals at remote field sites under harsh conditions. Astronomical sources can be used for independent absolute calibration procedures. Under ideal conditions Jupiter is an excellent source, as it can provide more light than the brightest star. We use Jupiter to calibrate an auroral MSP network.
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.
Kirsti Kauristie, Minna Myllys, Noora Partamies, Ari Viljanen, Pyry Peitso, Liisa Juusola, Shabana Ahmadzai, Vikramjit Singh, Ralf Keil, Unai Martinez, Alexej Luginin, Alexi Glover, Vicente Navarro, and Tero Raita
Geosci. Instrum. Method. Data Syst., 5, 253–262, https://doi.org/10.5194/gi-5-253-2016, https://doi.org/10.5194/gi-5-253-2016, 2016
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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.
P. Prikryl, R. Ghoddousi-Fard, E. G. Thomas, J. M. Ruohoniemi, S. G. Shepherd, P. T. Jayachandran, D. W. Danskin, E. Spanswick, Y. Zhang, Y. Jiao, and Y. T. Morton
Ann. Geophys., 33, 637–656, https://doi.org/10.5194/angeo-33-637-2015, https://doi.org/10.5194/angeo-33-637-2015, 2015
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Rapid fluctuations in amplitude and phase of radio waves passing through the ionosphere degrade GPS positional accuracy and can lead to navigational errors, particularly during geomagnetic storms. As a function of magnetic latitude and local time, regions of GPS phase scintillation at high latitudes are identified in the context of coupling between the solar wind and the magnetosphere-ionosphere system, which primarily depends on the interplanetary magnetic field magnitude and orientation.
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
E. E. Woodfield, R. B. Horne, S. A. Glauert, J. D. Menietti, and Y. Y. Shprits
Ann. Geophys., 31, 1619–1630, https://doi.org/10.5194/angeo-31-1619-2013, https://doi.org/10.5194/angeo-31-1619-2013, 2013
J. Liang, F. Jiang, E. Donovan, E. Spanswick, V. Angelopoulos, and R. Strangeway
Ann. Geophys., 31, 1077–1101, https://doi.org/10.5194/angeo-31-1077-2013, https://doi.org/10.5194/angeo-31-1077-2013, 2013
P. Prikryl, R. Ghoddousi-Fard, B. S. R. Kunduri, E. G. Thomas, A. J. Coster, P. T. Jayachandran, E. Spanswick, and D. W. Danskin
Ann. Geophys., 31, 805–816, https://doi.org/10.5194/angeo-31-805-2013, https://doi.org/10.5194/angeo-31-805-2013, 2013
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
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Vibration error compensation algorithm in the development of laser interference absolute gravimeters
Design and applications of drilling trajectory measurement instrumentation in an ultra-deep borehole based on a fiber-optic gyro
Optical laboratory facilities at the Finnish Meteorological Institute – Arctic Research Centre
Results from the intercalibration of optical low light calibration sources 2011
Multi-scale auroral observations in Apatity: winter 2010–2011
Qiong Wu, Yuntian Teng, Xiaomei Wang, Yanxiong Wu, and Yang Zhang
Geosci. Instrum. Method. Data Syst., 10, 113–122, https://doi.org/10.5194/gi-10-113-2021, https://doi.org/10.5194/gi-10-113-2021, 2021
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Laser interference absolute gravimeters are high-precision gravimetry instruments. However, the error caused by self-sysetm and enviromental vibration has become the primary obstacle limiting their accuracy and stability. The present work addresses this issue by proposing a global search optimization algorithm that determines the optimal absolute value of gravity. The results evaluated by numerical calculations demonstrate that this algorithm provides a substantial anti-vibration capability.
Yimin Liu, Chenghu Wang, Guangqiang Luo, and Weifeng Ji
Geosci. Instrum. Method. Data Syst., 9, 79–104, https://doi.org/10.5194/gi-9-79-2020, https://doi.org/10.5194/gi-9-79-2020, 2020
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This paper developed a drilling trajectory measuring instrumentation (DTMI) based on the interference fiber-optic gyro (FOG), which can work continuously, for 4 h, in an environment where the ambient temperature does not exceed 270 °C and the pressure does not exceed 120 MPa in an ultra-deep borehole. The DTMI has the characteristic of anti-electromagnetic interference; therefore,this DTMI has great potential in the promotion and development of geological drilling technology.
Kaisa Lakkala, Hanne Suokanerva, Juha Matti Karhu, Antti Aarva, Antti Poikonen, Tomi Karppinen, Markku Ahponen, Henna-Reetta Hannula, Anna Kontu, and Esko Kyrö
Geosci. Instrum. Method. Data Syst., 5, 315–320, https://doi.org/10.5194/gi-5-315-2016, https://doi.org/10.5194/gi-5-315-2016, 2016
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This paper describes the laboratory facilities at the Finnish Meteorological Institute – Arctic Research Centre (FMI-ARC). They comprise an optical laboratory, a facility for biological studies, and an office. The facilities are ideal for responding to the needs of international multidisciplinary research, giving the possibility to calibrate and characterize the research instruments as well as handle and store samples.
B. U. E. Brändström, C.-F. Enell, O. Widell, T. Hansson, D. Whiter, S. Mäkinen, D. Mikhaylova, K. Axelsson, F. Sigernes, N. Gulbrandsen, N. M. Schlatter, A. G. Gjendem, L. Cai, J. P. Reistad, M. Daae, T. D. Demissie, Y. L. Andalsvik, O. Roberts, S. Poluyanov, and S. Chernouss
Geosci. Instrum. Method. Data Syst., 1, 43–51, https://doi.org/10.5194/gi-1-43-2012, https://doi.org/10.5194/gi-1-43-2012, 2012
B. V. Kozelov, S. V. Pilgaev, L. P. Borovkov, and V. E. Yurov
Geosci. Instrum. Method. Data Syst., 1, 1–6, https://doi.org/10.5194/gi-1-1-2012, https://doi.org/10.5194/gi-1-1-2012, 2012
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