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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David Docquier, Giorgia Di Capua, Reik V. Donner, Carlos A. L. Pires, Amélie Simon, and Stéphane Vannitsem
Nonlin. Processes Geophys., 31, 115–136, https://doi.org/10.5194/npg-31-115-2024, https://doi.org/10.5194/npg-31-115-2024, 2024
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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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Heavy rainfall in tropical regions interacts with mid-latitude circulation patterns, and this interaction can explain weather patterns in the Northern Hemisphere during summer. In this analysis we detect these tropical–extratropical interaction pattern both in observational datasets and data obtained by atmospheric models and assess how well atmospheric models can reproduce the observed patterns. We find a good agreement although these relationships are weaker in model data.
Tommaso Alberti, Reik V. Donner, and Stéphane Vannitsem
Earth Syst. Dynam., 12, 837–855, https://doi.org/10.5194/esd-12-837-2021, https://doi.org/10.5194/esd-12-837-2021, 2021
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Frederik Wolf, Aiko Voigt, and Reik V. Donner
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In our work, we employ complex networks to study the relation between the time mean position of the intertropical convergence zone (ITCZ) and sea surface temperature (SST) variability. We show that the information hidden in different spatial SST correlation patterns, which we access utilizing complex networks, is strongly correlated with the time mean position of the ITCZ. This research contributes to the ongoing discussion on drivers of the annual migration of the ITCZ.
Frederik Wolf, Ugur Ozturk, Kevin Cheung, and Reik V. Donner
Earth Syst. Dynam., 12, 295–312, https://doi.org/10.5194/esd-12-295-2021, https://doi.org/10.5194/esd-12-295-2021, 2021
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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
Giorgia Di Capua, Marlene Kretschmer, Reik V. Donner, Bart van den Hurk, Ramesh Vellore, Raghavan Krishnan, and Dim Coumou
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
Short summary
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
Ann. Geophys., 36, 287–299, https://doi.org/10.5194/angeo-36-287-2018, https://doi.org/10.5194/angeo-36-287-2018, 2018
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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
Short summary
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
Short summary
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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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In this study we systematically quantify simultaneities between meteorological extremes and the timing of flowering of four shrub species across Germany by using event coincidence analysis. Our study confirms previous findings of experimental studies, highlighting the impact of early spring temperatures on the flowering of the investigated plants. Additionally, the analysis reveals statistically significant indications of an influence of temperature extremes in the fall preceding the flowering.
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
Short summary
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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Paleoclimate records from cave deposits allow the reconstruction of Holocene dynamics of the Asian monsoon system, an important tipping element in Earth's climate. Employing recently developed techniques of nonlinear time series analysis reveals several robust and continental-scale regime shifts in the complexity of monsoonal variability. These regime shifts might have played an important role as drivers of migration, cultural change, and societal collapse during the past 10,000 years.
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
Short summary
We use visibility graphs to characterize asymmetries in the dynamics of sunspot areas in both solar hemispheres. Our analysis provides deep insights into the potential and limitations of this method, revealing a complex interplay between effects due to statistical versus dynamical properties of the observed data. Temporal changes in the hemispheric predominance of the graph connectivity are found to lag those directly associated with the total hemispheric sunspot areas themselves.
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
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