Timo Asikainen

Timo Asikainen

Associate Professor (tenure track)

I'm a space scientist working at the Space Physics and Astronomy Research Unit at the University of Oulu, Finland. My field is Space Climate, which concentrates on long-term variation of Solar activity and its effects in near-Earth space, atmosphere and climate.

This research field is highly multidisciplidary and is at the cross-section of space and climate science. One important focus point is to understand the various ways the Sun can affect the climate system not only by solar radiation but by the continuous stream of magnetised plasma flowing out from the Sun, the solar wind. The latest research topic is to develop methods to predict solar activity and its effects in near-Earth space and climate system over long time scales. This type of research involves dealing with huge amounts of data from various sources (satellites, ground-based data, model data and climate re-analyses). This often requires application of statistical big data and machine learning methods.

  • Name:
    Timo Asikainen
  • Address:
    Space Physics and Astronomy Research Unit
    P.O. Box 3000,
    FIN-90014 University of Oulu
    Finland
  • Social profiles:

My research interests


Space climate and space weather
Solar effects on Earth's climate
Prediction of Space Climate
Energetic particles and radiation belts
Geomagnetic activity
Solar wind - magnetosphere interaction
Solar magnetism
Big Data methods for space science
Publications

Publications

Papers

2021

  1. Maliniemi, V., P. Arsenovic, T. Asikainen, C. Smith-Johnsen, A. Salminen, E. Rozanov, K. Mursula, Energetic electron precipitation - a novel driver of the polar vortex, Geophys. Res. Lett., 2021, under review
  2. Nesse Tyssøy, H., M. Sinnhuber, T. Asikainen, S. Bender, M. A. Clilverd, B. Funke, M. van de Kamp, J. M. Pettit, C. E. Randall, T. Reddmann, C. J. Rodger, E. Rozanov, C. Smith-Johnsen, T. Sukhodolov, P. T. Verronen, J. M. Wissing, O. Yakovchuk, HEPPA III intercomparison experiment on electron precipitation impacts, part I: Estimated ionization rates during a geomagnetic active period in April 2010, J. Geophys. Res. Space Phys., 2021, under review
  3. Sinnhuber M., Nesse Tyssøy, H., T. Asikainen, S. Bender, B. Funke, K. Hendrickx, J. M. Pettit, T. Reddmann, E. Rozanov, H. Schmidt, C. Smith-Johnsen, T. Sukhodolov, M.E. Szelag, M. van de Kamp, P. T. Verronen, J. M. Wissing, O. Yakovchuk, Heppa III intercomparison experiment on electron precipitation impacts, part II: Model-measurement intercomparison of nitric oxide (NO) during a geomagnetic storm in April 2010, J. Geophys. Res. Space Phys., 2021, submitted
  4. Edvartsen, J, V. Maliniemi, H. Nesse Tyssøy, T. Asikainen and S. Hatch, The Mansurov Effect: Real or a statistical artefact?, J. Geophys. Res. Space Phys., 2021, under review
  5. Holappa, L., R. Robinson, A. Pulkkinen, T. Asikainen and K. Mursula, Explicit IMF By-dependence in geomagnetic activity: quantifying ionospheric electrodynamics, J. Geophys. Res. Space Phys., 126, e2021JA029202, 2021
  6. Hamada, A., T. Asikainen and K. Mursula, A uniform series of low-latitude coronal holes in 1973-2018, Sol. Phys., 296, 40, 2021

2020

  1. George, H., E. Kilpua, A. Osmane, T. Asikainen, M. Kalliokoski, C.J. Rodger, S. Dubyagin and M. Palmroth, Outer Van Allen belt trapped and precipitating electron flux responses to two interplanetary magnetic clouds of opposite polarity, Ann. Geophys., 38, 931-951, 2020
  2. Salminen, A., T. Asikainen, V. Maliniemi and K. Mursula, Comparing the effects of solar-related and terrestrial drivers on the northern polar vortex, J. Space Weather Space Clim., 10, 56, 2020
  3. Salminen, A., T. Asikainen, V. Maliniemi and K. Mursula, Dependence of sudden stratospheric warmings on internal and external drivers, Geophysical Research Letters, 47, e2019GL086444, 2020
  4. Holappa, L., T. Asikainen and K. Mursula, Explicit IMF By-dependence in geomagnetic activity: modulation of precipitating electrons, Geophysical Research Letters, 47, e2019GL086676, 2020
  5. Kilpua, E., L. Juusola, M. Grandin, A. Kero, S. Dubyagin, N. Partamies, A. Osmane, H. George, M. Kalliokoski, T. Raita, T. Asikainen and M. Palmroth, Cosmic noise absorption signature of particle precipitation during ICME sheaths and ejecta, Ann. Geophys., 38, 557–574, 2020
  6. Asikainen, T., A. Salminen, V. Maliniemi and K. Mursula, Influence of enhanced planetary wave activity on the polar vortex enhancement related to energetic electron precipitation, Journal Geophysical Research: Atmospheres, 125, e2019JD032137, 2020
  7. Hamada, A., T. Asikainen, K. Mursula, New Homogeneous Dataset of Solar EUV Synoptic Maps from SOHO/EIT and SDO/AIA, Sol. Phys. 295, 2, 2020

2019

  1. Asikainen, T., New homogeneous composite of energetic electron fluxes from POES satellites: 2. Inter-calibration of SEM-1 and SEM-2 instruments for the telescope viewing direction, J. Geophys. Res. Space Phys., 124, 5761– 5782, 2019
  2. Palmroth, M., J. Praks, R. Vainio, P. Janhunen, E. Kilpua, N. Ganushkina, A. Afanasiev, M. Ala-Lahti, A. Alho, T. Asikainen et al., FORESAIL-1 cubesat mission to measure radiation belt losses and demonstrate de-orbiting, J. Geophys. Res. Space Phys., 124, 5783– 5799, 2019
  3. Maliniemi, V., T. Asikainen, A. Salminen and K. Mursula, Assessing North Atlantic winter climate response to geomagnetic activity and sunspots, Q J R Meteorol Soc., 145: 3780– 3789, 2019
  4. Salminen, A., T. Asikainen, V. Maliniemi and K. Mursula, Effect of energetic electron precipitation on the northern polar vortex: Explaining the QBO modulation via control of meridional circulation, J. Geophys. Res. Atmos., 124, 5807– 5821, 2019
  5. Asikainen T. and M. Ruopsa, New homogeneous composite of energetic electron fluxes from POES satellites: 1. Correction for background noise and orbital drift, J. Geophys. Res. Space Phys., 124, 1203– 1221, 2019

2018

  1. Maliniemi, V., T. Asikainen and K. Mursula, Decadal variability in the Northern Hemisphere winter circulation: Effects of different solar and terrestrial drivers, J. Atmos. Sol.-Terr. Phys., 179, p.40-54, 2018
  2. Hamada, A., T. Asikainen, I. Virtanen, I., K. Mursula, Automated Identification of Coronal Holes from Synoptic EUV Maps, Solar Physics 293: 71, 2018

2017

  1. Tsagouri, I., I. Galkin and T. Asikainen, Long-term predictions of space weather effects on the Earth's ionosphere, Adv. Space Res., 59, p. 351-365, 2017
  2. Asikainen, T., Calibrated and corrected POES/MEPED energetic particle observations, Chapter 3.3 in e-book “The ESPAS e-infrastructure: Access to data in near-Earth space”, Belehaki, A., M. Hapgood and J. Watermann eds., 978-2-7598-1949-2, 2017.

2016

  1. Maliniemi, V., T. Asikainen and K. Mursula, Effect of geomagnetic activity on the northern annular mode: QBO-dependence and the Holton-Tan relationship, J. Geophys. Res. Atmos., 121, 10043-10055, 2016
  2. Roy, I., T. Asikainen, V. Maliniemi and K. Mursula, Comparing the influence of sunspot activity and geomagnetic activity on winter surface climate, J. Atmos. Solar-Terr. Phys., 149, pp.167-179, 2016
  3. Asikainen, T. and M. Ruopsa, Solar wind drivers of energetic electron precipitation, J. Geophys. Res., 121 (3), 2209-2225, 2016

2015

  1. Juusola, L., K. Kauristie, M. van de Kamp, E. I. Tanskanen, K. Mursula, T. Asikainen, K. Andréeová, N. Partamies, H. Vanhamäki, and A. Viljanen, Solar wind control of ionospheric equivalent currents and their time derivatives, J. Geophys. Res. Space Physics, 120,doi:10.1002/2015JA021204, 2015

2014

  1. Holappa, L., K. Mursula and T. Asikainen, A new method to estimate annual solar wind parameters and contributions of different solar wind structures to geomagnetic activity, J. Geophys. Res., 119, 9407-9418, 2014
  2. Holappa, L., K. Mursula, T. Asikainen and I.G. Richardson, Annual fractions of high speed streams from principal component analysis of local geomagnetic activity, J. Geophys. Res. Space Physics, 119, 4544–4555, 2014
  3. Asikainen, T. and K. Mursula, Long-term relation between corrected NOAA/MEPED energetic proton fluxes and geomagnetic indices, J. Atmos. Solar-Terr. Phys., 113, pp. 29-38, 2014
  4. Maliniemi, V., T. Asikainen and K. Mursula, Spatial distribution of Northern Hemisphere winter temperatures during different phases of the solar cycle, J. Geophys. Res. Atmos.,119, 9752–9764, 2014

2013

  1. Asikainen, T. and K. Mursula, Correcting the NOAA/MEPED energetic electron fluxes for detector efficiency and proton contamination, J. Geophys. Res, 118, 6500–6510, 2013
  2. Maliniemi, V., T. Asikainen and K. Mursula, QBO dependent relation between electron precipitation and winter time surface temperature, J. Geophys. Res. Atmos., 118, 6302-6310, doi:, 2013
  3. Spencer, E., S. Patra, T. Asikainen, Magnetotail current contribution to the Dst Index Using the MT Index and the WINDMI model, Adv. Space Res., 52, Issue 11, 1974-1986, 2013
  4. Asikainen, T., K. Mursula and V. Maliniemi, Correction of detector noise and recalibration of NOAA/MEPED energetic proton fluxes, J. Geophys. Res., 117, A09204, 2012

2012

  1. Asikainen, T., K. Mursula and V. Maliniemi, Correction of detector noise and recalibration of NOAA/MEPED energetic proton fluxes, J. Geophys. Res., 117, A09204, 2012

2011

  1. Asikainen, T. and K. Mursula, Recalibration of NOAA/MEPED energetic proton measurements, J. Atmos. Sol.-Terr. Phys., 73, pp. 335-347, 2011

2010

  1. Asikainen, T., V. Maliniemi and K. Mursula, Modeling the contributions of ring, tail and magnetopause currents to the corrected Dst index, J. Geophys. Res., 115, A12203, 2010

2009

  1. Asikainen, T., Energetic Particles in the Cusp: A Cluster/RAPID view, in "The Cluster Active Archive: Studying the Earth's Space Plasma Environment", edited by H. Laakso, M. Taylor, C.P. Escoubet, p. 415-426, Astrophysics and Space Science Proceedings, ISBN: 978-90-481-3498-4, 2009

2008

  1. Asikainen, T. and K. Mursula, Energetic electron flux behavior at low L-shells and its relation to the South Atlantic Anomaly, J. Atmos. Sol.-Terr. Phys., 70, 532-538, 2008

2007

  1. Fear, R.C., S.E. Milan, A.N. Fazakerley, C.J. Owen, T. Asikainen, M.G.G.T. Taylor, E.A. Lucek, H. Rème, I. Dandouras and P.W. Daly, Motion of Flux Transfer Events: A Test of the Cooling Model, Annales Geophysicae, 25, 1669-1690, 2007

2006

  1. Asikainen, T. and K. Mursula, Reconnection and energetic particles at the edge of the exterior cusp, Annales Geophysicae, 24, 1949-1956, 2006

2005

  1. Asikainen, T., R. Kerttula, K. Mursula, R. Friedel, D. Baker, F. Soraas, J.F. Fennell and J.B. Blake, Global View of Energetic Particles During a Marjor Magnetic Storm, “The Inner Magnetosphere: Physics and Modeling”, edited by T.I. Pulkkinen, N.A. Tsyganenko and R.H.W. Friedel, Geophysical Monograph Series, Volume 155, p.97-104, 2005
  2. Asikainen, T. and K. Mursula, Energetic particle fluxes in the exterior cusp and the high-latitude dayside magnetosphere: Statistical results from the Cluster/RAPID instrument, Annales Geophysicae, 23, 2217-2230, 2005
  3. Asikainen, T. and K. Mursula, Filling of the South Atlantic Anomaly by energetic electrons during a great magnetic storm, Geophys. Res. Lett., Vol. 32, L16102, 2005
  4. Mursula, K., R. Kerttula, T. Asikainen, R. Friedel, A. Vaivads, F. Soeraas, M. Grande, M. Carter, P. W. Daly, T. A. Fritz, J. F. Fennell and A. Balogh CLUSTER/RAPID energetic electron observations at the dayside magnetospheric boundary, Adv. Space Res., 36, 1904-1908, 2005
  5. Kerttula, R., K. Mursula, T. Asikainen, R. Friedel, D. Baker, F. Soeraas, J. F. Fennell, J. B. Blake and M. Grande, Energetic particle acceleration during the main phase of a major magnetic storm, Adv. Space Res., 36, 1835-1839, 2005
Teaching

Teaching

I am regularly lecturing these courses at University of Oulu

Electromagnetism 1

Basic B.Sc. level

Plasma physics

Advanced M.Sc. level

Magnetospheric physics

Advanced M.Sc. level

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