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Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics
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Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics

A special issue of Atmosphere (ISSN 2073-4433). This special issue belongs to the section "Upper Atmosphere".

Deadline for manuscript submissions: closed (15 March 2021) | Viewed by 24939

Special Issue Editors

Dr. Giuseppina Nigro

E-Mail Website
Guest Editor
Department of Physics, University of Calabria, via P. Bucci cubo 31C, Arcavacata di Rende, 87036 Cosenza, Italy
Interests: fluid and magnetofluid turbulence; magnetic dynamo; numerical simulations; plasma physics; magnetohydrodynamic astrophysical plasma
Prof. Dr. Mariarosaria Falanga

E-Mail Website
Guest Editor
Dipartimento di Ingegneria dell'Informazione ed Elettrica e Matematica applicata/DIEM, Università di Salerno, via Giovanni Paolo II, 84084 Fisciano (SA), Italy
Interests: nonlinear processes; earthquakes; synchronization; volcanoes

Special Issue Information

Dear Colleagues,

In recent years, the Sun–Earth system has been the subject of both fundamental and applied research, with a variety of interdisciplinary approaches. In all those systems that are spanning the entire heliosphere, Sun and Earth included, the fundamental mechanism of energy transport, redistribution, and conversion almost always occurs in a multiscale manner. Due to the multiscale aspect of the aforementioned processes, scaling laws emerge in the statistics of the observable quantities detected in the solar atmosphere, the solar wind, the Earth’s magnetosphere, and the geophysical systems. The existence of these scaling laws has led to a widespread interest in these systems and the application of methods developed in the field of complex and nonlinear dynamics to their study. In fact, the quantification of nonlinear behavior, the evaluation of how the latter depends on the different conditions of the system, and the assessment of how the physical processes scale and evolve in time and space provide fundamental information for our understanding of these systems and their basic mechanisms. Therefore, the methods introduced in the field of instabilities, turbulence, chaos, and statistical mechanics have been applied not only to nonlinear data analysis but also to models and forecasting within the Sun–Earth system, being the subject of an ever-increasing field of research such as space weather, space climate, and nonlinear geophysics.

Shedding light on the processes occurring in natural systems over different time scales has relevant implications for hazards and modern monitoring. Fundamental contributions come from the use of combined multiparametric datasets, the adoption of innovative techniques, and multidisciplinary experimental approaches.

With this Special Issue, we propose to put forth the state-of-the-art of the models and the analysis dealing with multiscale processes developed for heliophysical and geophysical systems mainly focused on:

Solar magnetic field, dynamo and solar cycle;
Solar impulsive events: flares, coronal mass ejections;
Turbulence and nonlinear processes in space;
Sun–Earth processes, space weather, and space climate ;
Dynamo and earth magnetic field;
Nonlinear dynamics in geophysical systems;
Earth’s climate and atmosphere;
Hydrodynamical systems;
Statistical methods in geophysical context.

Dr. Giuseppina Nigro
Prof. Mariarosaria Falanga
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Atmosphere is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Dynamos
  • Solar flares and CMEs
  • Space plasmas
  • Space weather and space climate
  • Geophysical systems
  • Earth’s climate and atmosphere
  • Turbulence
  • Nonlinear dynamics
  • Complex systems
  • Statistical methods

Published Papers (11 papers)

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Research

23 pages, 4282 KiB  
Article
Tropospheric Delay in the Neapolitan and Vesuvius Areas (Italy) by Means of a Dense GPS Array: A Contribution for Weather Forecasting and Climate Monitoring
by Umberto Riccardi, Umberto Tammaro and Paolo Capuano
Atmosphere 2021, 12(9), 1225; https://doi.org/10.3390/atmos12091225 - 18 Sep 2021
Cited by 3 | Viewed by 2371
Abstract
Studying the spatiotemporal distribution and motion of water vapour (WV), the most variable greenhouse gas in the troposphere, is pivotal, not only for meteorology and climatology, but for geodesy, too. In fact, WV variability degrades, in an unpredictable way, almost all geodetic observation [...] Read more.
Studying the spatiotemporal distribution and motion of water vapour (WV), the most variable greenhouse gas in the troposphere, is pivotal, not only for meteorology and climatology, but for geodesy, too. In fact, WV variability degrades, in an unpredictable way, almost all geodetic observation based on the propagation of electromagnetic signal through the atmosphere. We use data collected on a dense GPS network, designed for the purposes of monitoring the active Neapolitan (Italy) volcanoes, to retrieve the tropospheric delay parameters and precipitable water vapour (PWV). This study has two main targets: (a) the analysis of long datasets (11 years) to extract trends of climatological meaning for the region; (b) studying the main features of the time evolution of the PWV during heavy raining events to gain knowledge on the preparatory stages of highly impacting thunderstorms. For the latter target, both differential and precise point positioning (PPP) techniques are used, and the results are compared and critically discussed. An increasing trend, amounting to about 2 mm/decades, has been recognized in the PWV time series, which is in agreement with the results achieved in previous studies for the Mediterranean area. A clear topographic effect is detected for the Vesuvius volcano sector of the network and a linear relationship between PWV and altitude is quantitatively assessed. This signature must be taken into account in any modelling for the atmospheric correction of geodetic and remote-sensing data (e.g., InSAR). Characteristic temporal evolutions were recognized in the PWV in the targeted thunderstorms (which occurred in 2019 and 2020), i.e., a sharp increase a few hours before the main rain event, followed by a rapid decrease when the thunderstorm vanished. Accounting for such a peculiar trend in the PWV could be useful for setting up possible early warning systems for those areas prone to flash flooding, thus potentially providing a tool for disaster risk reduction. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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15 pages, 5543 KiB  
Article
Tracking the Endogenous Dynamics of the Solfatara Volcano (Campi Flegrei, Italy) through the Analysis of Ground Thermal Image Temperatures
by Paola Cusano, Teresa Caputo, Enza De Lauro, Mariarosaria Falanga, Simona Petrosino, Fabio Sansivero and Giuseppe Vilardo
Atmosphere 2021, 12(8), 940; https://doi.org/10.3390/atmos12080940 - 22 Jul 2021
Cited by 9 | Viewed by 2146
Abstract
In the last decades, thermal infrared ground-based cameras have become effective tools to detect significant spatio-temporal anomalies in the hydrothermal/volcanic environment, possibly linked to impending eruptions. In this paper, we analyzed the temperature time-series recorded by the ground-based Thermal Infrared Radiometer permanent network [...] Read more.
In the last decades, thermal infrared ground-based cameras have become effective tools to detect significant spatio-temporal anomalies in the hydrothermal/volcanic environment, possibly linked to impending eruptions. In this paper, we analyzed the temperature time-series recorded by the ground-based Thermal Infrared Radiometer permanent network of INGV-OV, installed inside the Solfatara-Pisciarelli area, the most active fluid emission zones of the Campi Flegrei caldera (Italy). We investigated the temperatures’ behavior in the interval 25 June 2016–29 May 2020, with the aim of tracking possible endogenous hydrothermal/volcanic sources. We performed the Independent Component Analysis, the time evolution estimation of the spectral power, the cross-correlation and the Changing Points’ detection. We compared the obtained patterns with the behavior of atmospheric temperature and pressure, of the time-series recorded by the thermal camera of Mt. Vesuvius, of the local seismicity moment rate and of the CO2 emission flux. We found an overall influence of exogenous, large scale atmospheric effect, which dominated in 2016–2017. Starting from 2018, a clear endogenous forcing overcame the atmospheric factor, and dominated strongly soil temperature variations until the end of the observations. This paper highlights the importance of monitoring and investigating the soil temperature in volcanic environments, as well as the atmospheric parameters. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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11 pages, 577 KiB  
Article
Stellar Turbulent Convection: The Multiscale Nature of the Solar Magnetic Signature
by Stefano Scardigli, Francesco Berrilli, Dario Del Moro and Luca Giovannelli
Atmosphere 2021, 12(8), 938; https://doi.org/10.3390/atmos12080938 - 22 Jul 2021
Cited by 2 | Viewed by 1746
Abstract
The multiscale dynamics associated with turbulent convection present in physical systems governed by very high Rayleigh numbers still remains a vividly disputed topic in the community of astrophysicists, and in general, among physicists dealing with heat transport by convection. The Sun is a [...] Read more.
The multiscale dynamics associated with turbulent convection present in physical systems governed by very high Rayleigh numbers still remains a vividly disputed topic in the community of astrophysicists, and in general, among physicists dealing with heat transport by convection. The Sun is a very close star for which detailed observations and estimations of physical properties on the surface, connected to the processes of the underlying convection zone, are possible. This makes the Sun a unique natural laboratory in which to investigate turbulent convection in the hard turbulence regime, a regime typical of systems characterized by high values of the Rayleigh number. In particular, it is possible to study the geometry of convection using the photospheric magnetic voids (or simply voids), the quasi-polygonal quiet regions nearly devoid of magnetic elements, which cover the whole solar surface and which form the solar magnetic network. This work presents the most extensive statistics, both in the spatial scales studied (1–80 Mm) and in the temporal duration (SC 23 and SC 24), to investigate the multiscale nature of solar magnetic patterns associated with the turbulent convection of our star. We show that the size distribution of the voids, in the 1–80 Mm range, for the 317,870 voids found in the 692 analyzed magnetograms, is basically described by an exponential function. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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8 pages, 439 KiB  
Article
Scaling Properties and Persistence of Long-Term Solar Activity
by Fabio Lepreti, Vincenzo Carbone and Antonio Vecchio
Atmosphere 2021, 12(6), 733; https://doi.org/10.3390/atmos12060733 - 08 Jun 2021
Cited by 2 | Viewed by 2027
Abstract
The long-range correlations associated with the presence of persistence are investigated by applying the detrended fluctuation analysis (DFA) on three different proxies of long-term solar activity. The considered datasets are a sunspot number reconstruction (SNR04) obtained from the atmospheric activity of the cosmogenic [...] Read more.
The long-range correlations associated with the presence of persistence are investigated by applying the detrended fluctuation analysis (DFA) on three different proxies of long-term solar activity. The considered datasets are a sunspot number reconstruction (SNR04) obtained from the atmospheric activity of the cosmogenic isotope 14C derived from tree rings, a total solar irradiance reconstruction (TSIR12) obtained from several 10Be ice core records from Greenland and Antarctica in combination with the global record of 14C in tree rings and a new multi-proxy sunspot number reconstruction (SNR18), also derived from 10Be datasets and the global 14C production series. The DFA scaling exponents found for the three time series are similar (lying in the range between 0.70 and 0.77) and the scaling ranges are comparable. These results indicate the presence of long-range correlations with persistence, in substantial agreement with the findings of previous studies carried out on other solar activity indices and proxies. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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13 pages, 586 KiB  
Article
Sign-Singularity Analysis of Field-Aligned Currents in the Ionosphere
by Giuseppe Consolini, Paola De Michelis, Igino Coco, Tommaso Alberti, Maria Federica Marcucci, Fabio Giannattasio and Roberta Tozzi
Atmosphere 2021, 12(6), 708; https://doi.org/10.3390/atmos12060708 - 31 May 2021
Cited by 4 | Viewed by 2532
Abstract
Field-aligned currents (FACs) flowing in the auroral ionosphere are a complex system of upward and downward currents, which play a fundamental role in the magnetosphere–ionosphere coupling and in the ionospheric heating. Here, using data from the ESA-Swarm multi-satellite mission, we studied the complex [...] Read more.
Field-aligned currents (FACs) flowing in the auroral ionosphere are a complex system of upward and downward currents, which play a fundamental role in the magnetosphere–ionosphere coupling and in the ionospheric heating. Here, using data from the ESA-Swarm multi-satellite mission, we studied the complex structure of FACs by investigating sign-singularity scaling features for two different conditions of a high-latitude substorm activity level as monitored by the AE index. The results clearly showed the sign-singular character of FACs supporting the complex and filamentary nature of these currents. Furthermore, we found evidence of the occurrence of a topological change of these current systems, which was accompanied by a change of the scaling features at spatial scales larger than 30 km. This change was interpreted in terms of a sort of symmetry-breaking phenomenon due to a dynamical topological transition of the FAC structure as a consequence of FACs and substorm current wedge intensification during substorms. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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18 pages, 1297 KiB  
Article
Electric Field Multifractal Features in the High-Latitude Ionosphere: CSES-01 Observations
by Giuseppe Consolini, Virgilio Quattrociocchi, Giulia D’Angelo, Tommaso Alberti, Mirko Piersanti, Maria Federica Marcucci and Paola De Michelis
Atmosphere 2021, 12(5), 646; https://doi.org/10.3390/atmos12050646 - 19 May 2021
Cited by 25 | Viewed by 2028
Abstract
In the polar ionosphere, the electric field is characterized by broadband and power law spectral densities at small/short spatio-temporal scales, which support a possible turbulent nature of the electric field fluctuations. Here, we investigate the multifractal character of the full three-dimensional electric field [...] Read more.
In the polar ionosphere, the electric field is characterized by broadband and power law spectral densities at small/short spatio-temporal scales, which support a possible turbulent nature of the electric field fluctuations. Here, we investigate the multifractal character of the full three-dimensional electric field in the polar ionosphere as recorded on board the first Chinese Seismo-Electromagnetic Satellite (CSES-01). The results of our analysis prove a clear different degree of multifractality of the electric field fluctuations approaching either the polar cap trailing edge or the auroral region. The observed differences in the multifractal character are interpreted in terms of the different natures of the particle precipitation in the polar cap and in the auroral region. A possible link between the multifractal nature of electric field fluctuations, parallel to the geomagnetic field, and filamentation of field aligned currents (FACs) is established. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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6 pages, 280 KiB  
Article
The Signal to Noise Ratio and the Completeness Magnitude: The Effect of the COVID-19 Lockdown
by Cataldo Godano, Vincenzo Convertito and Nicola Alessandro Pino
Atmosphere 2021, 12(5), 525; https://doi.org/10.3390/atmos12050525 - 21 Apr 2021
Cited by 2 | Viewed by 1833
Abstract
We analyse the earthquakes catalogues for Italy, South California, and Greece across the COVID-19 lockdown period for each country. The results for Italy and Greece show that, even if the reduction of the signal to noise ratio has improved the earthquake detection capability, [...] Read more.
We analyse the earthquakes catalogues for Italy, South California, and Greece across the COVID-19 lockdown period for each country. The results for Italy and Greece show that, even if the reduction of the signal to noise ratio has improved the earthquake detection capability, the completeness magnitude remains substantially unchanged, making the improved detection capability ineffective from the statistical point of view. A slight reduction (0.2) of the completeness magnitude is observed for South California, likely related to the relatively higher number of seismic stations located close to urban areas. Our findings suggest that—given the present configuration of the seismic network considered here—only an important decrease in the station spacing can produce a significant decrease of the completeness magnitude. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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14 pages, 1921 KiB  
Article
Self-Organization through the Inner Heliosphere: Insights from Parker Solar Probe
by Mirko Stumpo, Virgilio Quattrociocchi, Simone Benella, Tommaso Alberti and Giuseppe Consolini
Atmosphere 2021, 12(3), 321; https://doi.org/10.3390/atmos12030321 - 28 Feb 2021
Cited by 5 | Viewed by 2188
Abstract
The interplanetary medium variability has been extensively studied by means of different approaches showing the existence of a wide variety of dynamical features, such as self-similarity, self-organization, turbulence and intermittency, and so on. Recently, by means of Parker solar probe measurements, it has [...] Read more.
The interplanetary medium variability has been extensively studied by means of different approaches showing the existence of a wide variety of dynamical features, such as self-similarity, self-organization, turbulence and intermittency, and so on. Recently, by means of Parker solar probe measurements, it has been found that solar wind magnetic field fluctuations in the inertial range show a clear transition near 0.4 AU, both in terms of spectral features and multifractal properties. This breakdown of the scaling features has been interpreted as the evidence of a dynamical phase transition. Here, by using the Klimontovich S-theorem, we investigate how the process of self-organization is under way through the inner heliosphere, going deeper into the characterization of this dynamical phase transition by measuring the evolution of entropic-based measures through the inner heliosphere. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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28 pages, 4884 KiB  
Article
Assessment of Trends and Uncertainties in the Atmospheric Boundary Layer Height Estimated Using Radiosounding Observations over Europe
by Fabio Madonna, Donato Summa, Paolo Di Girolamo, Fabrizio Marra, Yuanzu Wang and Marco Rosoldi
Atmosphere 2021, 12(3), 301; https://doi.org/10.3390/atmos12030301 - 25 Feb 2021
Cited by 12 | Viewed by 2512
Abstract
Trends in atmospheric boundary layer height may represent an indication of climate changes. The related modified interaction between the surface and free atmosphere affects both thermodynamics variables and dilution of chemical constituents. Boundary layer is also a major player in various feedback mechanisms [...] Read more.
Trends in atmospheric boundary layer height may represent an indication of climate changes. The related modified interaction between the surface and free atmosphere affects both thermodynamics variables and dilution of chemical constituents. Boundary layer is also a major player in various feedback mechanisms of interest for climate models. This paper investigates trends in the nocturnal and convective boundary layer height at mid-latitudes in Europe using radiosounding profiles from the Integrated Global Radiosounding Archive (IGRA). Atmospheric data from the European Centre for Medium-Range Weather Forecasts (ECMWF) ReAnalysis v5 (ERA5) and from the GCOS Reference Upper-Air Network (GRUAN) Lindenberg station are used as intercomparison datasets for the study of structural and parametric uncertainties in the trend analysis. Trends are calculated after the removal of the lag-1 autocorrelation term for each time series. The study confirms the large differences reported in literature between the boundary layer height estimates obtained with the two different algorithms used for IGRA and ERA5 data: ERA5 shows a density distribution with median values of 350 m and 1150 m for the night and the daytime data, respectively, while the corresponding IGRA median values are of 1150 m and 1750 m. An overall good agreement between the estimated trends is found for nighttime data, while daytime ERA5 boundary layer height estimates over Europe are characterized by a lower spatial homogeneity than IGRA. Parametric uncertainties due to missing data in both the time and space domain are also investigated: the former is not exceeding 1.5 m, while the latter are within 10 m during night and 17 m during the day. Recommendations on dataset filtering based on time series completeness are provided. Finally, the comparison between the Lindenberg data as processed at high-resolution by GRUAN and as provided to IGRA at a lower resolution, shows the significant impact of using high-resolution data in the determination of the boundary layer height, with differences from about 200 m to 450 m for both night and day, as well as a large deviation in the estimated trend. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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10 pages, 1109 KiB  
Article
Accelerated Climate Changes in Weddell Sea Region of Antarctica Detected by Extreme Values Theory
by Giuseppe Prete, Vincenzo Capparelli, Fabio Lepreti and Vincenzo Carbone
Atmosphere 2021, 12(2), 209; https://doi.org/10.3390/atmos12020209 - 04 Feb 2021
Cited by 3 | Viewed by 1642
Abstract
On 13 February 2020, The Guardian, followed by many other newspapers and websites, published the news that on 9 February 2020, Antarctic air temperatures rose to about 20.75 ∘C in a base logged at Seymour Island. This value has not yet been [...] Read more.
On 13 February 2020, The Guardian, followed by many other newspapers and websites, published the news that on 9 February 2020, Antarctic air temperatures rose to about 20.75 ∘C in a base logged at Seymour Island. This value has not yet been validated by the WMO (World Meteorological Organization), but it is not the first time that an extreme temperature was registered in these locations. The recorded temperatures have often been described as “abnormal and anomalous”, according to a statement made by scientists working at the Antarctic bases. Since polar regions have shown the most rapid rates of climate change in recent years, this abnormality is of primary interest in the context of vulnerability of the Antarctic to climate changes. Using data detected at different Antarctic bases, we investigate yearly maxima and minima of recorded temperatures, in order to establish whether they can be considered as usual extreme events or abnormal. We found evidence for disagreement with the extreme values theory, indicating accelerated climate changes in the Antarctic, that is, a local warming rate that is much faster than global averages. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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11 pages, 2345 KiB  
Article
Stochastic Resonance Observed in Aerosol Optical Depth Time Series
by Mariarosaria Falanga, Enza De Lauro and Salvatore de Martino
Atmosphere 2020, 11(5), 502; https://doi.org/10.3390/atmos11050502 - 13 May 2020
Cited by 2 | Viewed by 2442
Abstract
We analyzed the aerosol optical depth time series retrieved from daily satellite Moderate-Resolution Imaging Spectroradiometer measurements. The investigated geographic area includes Italy and the Mediterranean Sea. By performing second- and fourth-order statistics analyses, the dynamics can be decomposed into two sources, the main [...] Read more.
We analyzed the aerosol optical depth time series retrieved from daily satellite Moderate-Resolution Imaging Spectroradiometer measurements. The investigated geographic area includes Italy and the Mediterranean Sea. By performing second- and fourth-order statistics analyses, the dynamics can be decomposed into two sources, the main of which is the annual cycle. The residence time distribution is made of local maxima over an exponential behavior. The two successive peaks are located at about 200 and 600 days. This allows us to hypothesize a stochastic resonance phenomenon in the dynamics of aerosol optical depth. The characteristic periodicity of the resonance is on the annual timescale, and the asymmetric double-well potential is provided by two different regimes for the values of the aerosol optical depth in winter and summer time. This means that a simple, although stochastic, differential equation can represent the time evolution of the optical depth, at least concerning its component related to the annual cycle. Full article
(This article belongs to the Special Issue Modeling Multiscale Dynamics by Statistical Mechanics in Heliophysics and Geophysics)
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