Articles | Volume 20, issue 6
https://doi.org/10.5194/npg-20-965-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/npg-20-965-2013
© Author(s) 2013. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Correlation-based characterisation of time-varying dynamical complexity in the Earth's magnetosphere
R. V. Donner
Department of Biogeochemical Integration, Max Planck Institute for Biogeochemistry, Hans-Knöll-Straße 10, 07745 Jena, Germany
Research Domain IV – Transdisciplinary Concepts & Methods, Potsdam Institute for Climate Impact Research, Telegrafenberg A31, 14473 Potsdam, Germany
G. Balasis
Institute for Astronomy, Astrophysics, Space Applications and Remote Sensing, National Observatory of Athens, I. Metaxa & Vas. Pavlou St., 15236, Penteli, Greece
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Giorgia Di Capua, Dim Coumou, Bart van den Hurk, Antje Weisheimer, Andrew G. Turner, and Reik V. Donner
Weather Clim. Dynam., 4, 701–723, https://doi.org/10.5194/wcd-4-701-2023, https://doi.org/10.5194/wcd-4-701-2023, 2023
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EGUsphere, https://doi.org/10.5194/egusphere-2023-1412, https://doi.org/10.5194/egusphere-2023-1412, 2023
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We demonstrate with a causality analysis that an important recurrent summer atmospheric pattern, the so-called East Atlantic teleconnection, is influenced by the extratropical North Atlantic in spring during the second half of the 20th century. This causal link is, however, not well represented by our evaluated seasonal climate prediction system. We show that simulations able to reproduce this link show improved surface climate prediction credibility over those that do not.
Tommaso Alberti, Reik V. Donner, and Stéphane Vannitsem
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Frederik Wolf, Aiko Voigt, and Reik V. Donner
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Frederik Wolf, Ugur Ozturk, Kevin Cheung, and Reik V. Donner
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Motivated by a lacking onset prediction scheme, we examine the temporal evolution of synchronous heavy rainfall associated with the East Asian Monsoon System employing a network approach. We find, that the evolution of the Baiu front is associated with the formation of a spatially separated double band of synchronous rainfall. Furthermore, we identify the South Asian Anticyclone and the North Pacific Subtropical High as the main drivers, which have been assumed to be independent previously.
Giorgia Di Capua, Jakob Runge, Reik V. Donner, Bart van den Hurk, Andrew G. Turner, Ramesh Vellore, Raghavan Krishnan, and Dim Coumou
Weather Clim. Dynam., 1, 519–539, https://doi.org/10.5194/wcd-1-519-2020, https://doi.org/10.5194/wcd-1-519-2020, 2020
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Jaqueline Lekscha and Reik V. Donner
Nonlin. Processes Geophys., 27, 261–275, https://doi.org/10.5194/npg-27-261-2020, https://doi.org/10.5194/npg-27-261-2020, 2020
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Earth Syst. Dynam., 11, 17–34, https://doi.org/10.5194/esd-11-17-2020, https://doi.org/10.5194/esd-11-17-2020, 2020
Short summary
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Drivers from both the mid-latitudes and the tropical regions have been proposed to influence the Indian summer monsoon (ISM) subseasonal variability. To understand the relative importance of tropical and mid-latitude drivers, we apply recently developed causal discovery techniques to disentangle the causal relationships among these processes. Our results show that there is indeed a two-way interaction between the mid-latitude circulation and ISM rainfall over central India.
Giorgia Di Capua, Marlene Kretschmer, Reik V. Donner, Bart van den Hurk, Ramesh Vellore, Raghavan Krishnan, and Dim Coumou
Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2019-11, https://doi.org/10.5194/esd-2019-11, 2019
Manuscript not accepted for further review
Short summary
Short summary
Both drivers from the mid-latitudes and from the tropical regions have been proposed to influence the Indian summer monsoon (ISM) subseasonal variability. To understand the relative importance of tropical and mid-latitude drivers, we apply recently developed causal discovery techniques to disentangle the causal relationships among these processes. Our results show that there is indeed a two-way interaction between the mid-latitude circulation and ISM rainfall over central India.
Constantinos Papadimitriou, Georgios Balasis, Ioannis A. Daglis, and Omiros Giannakis
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Swarm is the fourth Earth Explorer mission of the European Space Agency (ESA), launched on 23 November 2013. The mission provides an opportunity for better knowledge of the near-Earth electromagnetic environment. This study presents an initial attempt to derive an ultra low-frequency (ULF) wave index from low-Earth orbit satellite data. The technique can be potentially used to define a new product from the mission, the Swarm ULF wave index, which would be suitable for space weather applications.
Tim Kittel, Catrin Ciemer, Nastaran Lotfi, Thomas Peron, Francisco Rodrigues, Jürgen Kurths, and Reik V. Donner
Nonlin. Processes Geophys. Discuss., https://doi.org/10.5194/npg-2017-69, https://doi.org/10.5194/npg-2017-69, 2017
Revised manuscript not accepted
Jasper G. Franke, Johannes P. Werner, and Reik V. Donner
Clim. Past, 13, 1593–1608, https://doi.org/10.5194/cp-13-1593-2017, https://doi.org/10.5194/cp-13-1593-2017, 2017
Short summary
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We apply evolving functional network analysis, a tool for studying temporal changes of the spatial co-variability structure, to a set of
Late Holocene paleoclimate proxy records covering the last two millennia. The emerging patterns obtained by our analysis are related to
long-term changes in the dominant mode of atmospheric circulation in the region, the North Atlantic Oscillation (NAO). We obtain a
qualitative reconstruction of the NAO long-term variability over the entire Common Era.
Lukas Baumbach, Jonatan F. Siegmund, Magdalena Mittermeier, and Reik V. Donner
Biogeosciences, 14, 4891–4903, https://doi.org/10.5194/bg-14-4891-2017, https://doi.org/10.5194/bg-14-4891-2017, 2017
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Jonatan F. Siegmund, Marc Wiedermann, Jonathan F. Donges, and Reik V. Donner
Biogeosciences, 13, 5541–5555, https://doi.org/10.5194/bg-13-5541-2016, https://doi.org/10.5194/bg-13-5541-2016, 2016
Short summary
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Stelios M. Potirakis, Yiannis Contoyiannis, Nikolaos S. Melis, John Kopanas, George Antonopoulos, Georgios Balasis, Charalampos Kontoes, Constantinos Nomicos, and Konstantinos Eftaxias
Nonlin. Processes Geophys., 23, 223–240, https://doi.org/10.5194/npg-23-223-2016, https://doi.org/10.5194/npg-23-223-2016, 2016
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Short summary
Based on the methods of critical fluctuations and natural time, we have shown that the fracture-induced MHz electromagnetic emissions recorded by two stations in our network prior to two recent significant earthquakes that occurred in Cephalonia present criticality characteristics, implying that they emerge from a system in critical state.
M. Georgiou, I. A. Daglis, E. Zesta, G. Balasis, I. R. Mann, C. Katsavrias, and K. Tsinganos
Ann. Geophys., 33, 1431–1442, https://doi.org/10.5194/angeo-33-1431-2015, https://doi.org/10.5194/angeo-33-1431-2015, 2015
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Short summary
Our study demonstrates a remarkable association between the earthward penetration of ULF waves and radiation belt electron enhancements during four magnetic storms that occurred in 2001. In the past, ULF waves had been observed at unusual depths during rare superstorms. But ULF wave activity, reaching magnetic shells as low as 2, was also observed during relatively intense storms when it played a key role in diffusing electrons radially inward and thereby accelerating them to higher energies.
G. Balasis, I. A. Daglis, I. R. Mann, C. Papadimitriou, E. Zesta, M. Georgiou, R. Haagmans, and K. Tsinganos
Ann. Geophys., 33, 1237–1252, https://doi.org/10.5194/angeo-33-1237-2015, https://doi.org/10.5194/angeo-33-1237-2015, 2015
J. F. Donges, R. V. Donner, N. Marwan, S. F. M. Breitenbach, K. Rehfeld, and J. Kurths
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Y. Zou, R. V. Donner, N. Marwan, M. Small, and J. Kurths
Nonlin. Processes Geophys., 21, 1113–1126, https://doi.org/10.5194/npg-21-1113-2014, https://doi.org/10.5194/npg-21-1113-2014, 2014
Short summary
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S. M. Potirakis, K. Eftaxias, G. Balasis, J. Kopanas, G. Antonopoulos, and A. Kalimeris
Nat. Hazards Earth Syst. Sci. Discuss., https://doi.org/10.5194/nhessd-2-2981-2014, https://doi.org/10.5194/nhessd-2-2981-2014, 2014
Preprint withdrawn