scholarly journals Geosystemics View of Earthquakes

Entropy ◽  
2019 ◽  
Vol 21 (4) ◽  
pp. 412 ◽  
Author(s):  
Angelo De Santis ◽  
Cristoforo Abbattista ◽  
Lucilla Alfonsi ◽  
Leonardo Amoruso ◽  
Saioa A. Campuzano ◽  
...  

Earthquakes are the most energetic phenomena in the lithosphere: their study and comprehension are greatly worth doing because of the obvious importance for society. Geosystemics intends to study the Earth system as a whole, looking at the possible couplings among the different geo-layers, i.e., from the earth’s interior to the above atmosphere. It uses specific universal tools to integrate different methods that can be applied to multi-parameter data, often taken on different platforms (e.g., ground, marine or satellite observations). Its main objective is to understand the particular phenomenon of interest from a holistic point of view. Central is the use of entropy, together with other physical quantities that will be introduced case by case. In this paper, we will deal with earthquakes, as final part of a long-term chain of processes involving, not only the interaction between different components of the Earth’s interior but also the coupling of the solid earth with the above neutral or ionized atmosphere, and finally culminating with the main rupture along the fault of concern. Particular emphasis will be given to some Italian seismic sequences.


2020 ◽  
Author(s):  
Gianfranco Cianchini ◽  

<p>Earthquakes, the most energetic phenomena in the lithosphere, often cause danger and casualties: thus, their study and comprehension are greatly worth doing because of the obvious importance for society. Geosystemics intends to offer a way to study the Earth system by viewing it as a whole, looking at the possible couplings among the different geo-layers, i.e., from the earth’s interior up to the ionosphere through the atmosphere. It uses specific universal tools to integrate different methods that can be applied to multi-parameter data, often taken on different platforms (e.g., ground, marine or satellite observations). Its main aim is to understand the particular phenomenon of interest from a holistic point of view. Central is the use of entropy, together with other physical quantities that are introduced case by case. In this paper, we will deal with earthquakes, as final part of a long-term chain of processes involving, not only the interaction between different components of the Earth’s interior but also the coupling of the solid earth with the above neutral or ionized atmosphere, and finally culminating with the main rupture along the fault of concern. Particular emphasis will be given to some Italian seismic sequences.</p>



2018 ◽  
Author(s):  
Angelo De Santis ◽  
Gianfranco Cianchini ◽  
Rita Di Giovambattista ◽  
Cristoforo Abbattista ◽  
Lucilla Alfonsi ◽  
...  

Abstract. Geosystemics (De Santis 2009, 2014) studies the Earth system as a whole focusing on the possible coupling among the Earth layers (the so called geo-layers), and using universal tools to integrate different methods that can be applied to multi-parameter data, often taken on different platforms. Its main objective is to understand the particular phenomenon of interest from a holistic point of view. In this paper we will deal with earthquakes, considered as a long term chain of processes involving, not only the interaction between different components of the Earth’s interior, but also the coupling of the solid earth with the above neutral and ionized atmosphere, and finally culminating with the main rupture along the fault of concern (De Santis et al., 2015a). Some case studies (particular emphasis is given to recent central Italy earthquakes) will be discussed in the frame of the geosystemic approach for better understanding the physics of the underlying complex dynamical system.



2007 ◽  
Vol 25 (1) ◽  
pp. 255-269 ◽  
Author(s):  
V. M. Vasyliūnas

Abstract. Magnetosphere-ionosphere interactions involve electric currents that circulate between the two regions; the associated Lorentz forces, existing in both regions as matched opposite pairs, are generally viewed as the primary mechanism by which linear momentum, derived ultimately from solar wind flow, is transferred from the magnetosphere to the ionosphere, where it is further transferred by collisions to the neutral atmosphere. For a given total amount of current, however, the total force is proportional to ℒB and in general, since ℒ2B~ constant by flux conservation, is much larger in the ionosphere than in the magnetosphere (ℒ = effective length, B = magnetic field). The magnetosphere may be described as possesing a mechanical advantage: the Lorentz force in it is coupled with a Lorentz force in the ionosphere that has been amplified by a factor given approximately by the square root of magnetic field magnitude ratio (~20 to 40 on field lines connected to the outer magnetosphere). The linear momentum transferred to the ionosphere (and thence to the atmosphere) as the result of magnetic stresses applied by the magnetosphere can thus be much larger than the momentum supplied by the solar wind through tangential stress. The added linear momentum comes from within the Earth, extracted by the Lorentz force on currents that arise as a consequence of magnetic perturbation fields from the ionosphere (specifically, the shielding currents within the Earth that keep out the time-varying external fields). This implies at once that Fukushima's theorem on the vanishing of ground-level magnetic perturbations cannot be fully applicable, a conclusion confirmed by re-examining the assumptions from which the theorem is derived. To balance the inferred Lorentz force within the Earth's interior, there must exist an antisunward mechanical stress there, only a small part of which is the acceleration of the entire Earth system by the net force exerted on it by the solar wind. The solar-wind interaction can thus give rise to internal forces, significantly larger than the force exerted by the solar wind itself, between the ionosphere and the neutral atmosphere as well as within the current-carrying regions of the Earth's interior.



2017 ◽  
Vol 14 (9) ◽  
pp. 2343-2357 ◽  
Author(s):  
Thomas Kaminski ◽  
Pierre-Philippe Mathieu

Abstract. The vehicles that fly the satellite into a model of the Earth system are observation operators. They provide the link between the quantities simulated by the model and the quantities observed from space, either directly (spectral radiance) or indirectly estimated through a retrieval scheme (biogeophysical variables). By doing so, observation operators enable modellers to properly compare, evaluate, and constrain their models with the model analogue of the satellite observations. This paper provides the formalism and a few examples of how observation operators can be used in combination with data assimilation techniques to better ingest satellite products in a manner consistent with the dynamics of the Earth system expressed by models. It describes commonalities and potential synergies between assimilation and classical retrievals. This paper explains how the combination of observation operators and their derivatives (linearizations) form powerful research tools. It introduces a technique called automatic differentiation that greatly simplifies both the development and the maintenance of code for the evaluation of derivatives. Throughout this paper, a special focus lies on applications to the carbon cycle.



2021 ◽  
Author(s):  
Mireia Mestre ◽  
Juan Höfer

<p>Despite being major players on the global biogeochemical cycles, microorganisms are generally not included in holistic views of Earth’s system. The Microbial Conveyor Belt is a conceptual framework that represents a recurrent and cyclical flux of microorganisms across the globe, connecting distant ecosystems and Earth compartments. This long-range dispersion of microorganisms directly influences the microbial biogeography, the global cycling of inorganic and organic matter, and thus the Earth system’s functioning and long-term resilience. Planetary-scale human impacts disrupting the natural flux of microorganisms pose a major threat to the Microbial Conveyor Belt, thus compromising microbial ecosystem services. Perturbations that modify the natural dispersion of microorganisms are, for example, the modification of the intensity/direction of air fluxes and ocean currents due to climate change, the vanishing of certain dispersion vectors (e.g., species extinction or drying rivers) or the introduction of new ones (e.g., microplastics, wildfires). Transdisciplinary approaches are needed to disentangle the Microbial Conveyor Belt, its major threats and their consequences for Earth´s system resilience.</p>



1979 ◽  
Vol 82 ◽  
pp. 169-174 ◽  
Author(s):  
Nicole Capitaine

In order to improve the representation of nutation, the effect of elasticity of the Earth on the nutation in space and diurnal nutation of the terrestrial rotation axis is considered and its amplitude is evaluated for the principal terms. The choice between several methods taking this effect into account is discussed. A comparison with the effect induced on nutation by the existence of a liquid core in the Earth's interior shows that the consideration of elasticity alone cannot give any amelioration in the representation of nutation.



2019 ◽  
Vol 7 (1) ◽  
pp. 19-41 ◽  
Author(s):  
Frederic Hanusch ◽  
Frank Biermann

The Anthropocene as a new planetary epoch has brought to the foreground the deep-time interconnections of human agency with the earth system. Yet despite this recognition of strong temporal interdependencies, we still lack understanding of how societal and political organizations can manage interconnections that span several centuries and dozens of generations. This study pioneers the analysis of what we call “deep-time organizations.” We provide detailed comparative historical analyses of some of the oldest existing organizations worldwide from a variety of sectors, from the world’s oldest bank (Sveriges Riksbank) to the world’s oldest university (University of Al Quaraouiyine) and the world’s oldest dynasty (Imperial House of Japan). Based on our analysis, we formulate 12 initial design principles that could lay, if supported by further empirical research along similar lines, the basis for the construction and design of “deep-time organizations” for long-term challenges of earth system governance and planetary stewardship.



1851 ◽  
Vol 141 ◽  
pp. 511-547

In the first part of these researches, I have endeavoured, by generalizing the hypothesis on which is usually founded the theory of the earth’s figure, not only to improve that theory, but also to establish a secure basis for researches into the changes which may have taken place within and at the surface of the earth during the epochs of its geological history. Although I stated that no precise physical evidence could be adduced for the examination of the assumption that the molecules of the primitive fluid, supposed to have constituted the earth, retained their positions after solidification, it yet appears that such evidence exists, if we may be permitted to draw any conclusions relative to the physical properties of substances in the earth’s interior, from the observed physical properties of substances at its surface. Professor Bischof of Bonn, has shown that Granite contracts in volume in passing from the fluid to the solid crystalline state, from 1 to ⋅7481, Trachyte from 1 to ⋅8187, and Basalt from 1 to ⋅8960. The first of these rocks appears, as far as can be observed, to constitute the greater part of the earth; hence the assumption alluded to must be considered not only as superfluous, but as erroneous. In this Part it is my object to discover relations between the interior structure of the earth and phenomena observed at its surface, and also the effects of the reaction of the fluid nucleus, described in Article 6, Part I., upon the solid crust. I divide this Part into sections, each containing a distinct investigation, the order of arrangement of these sections being determined according to their fundamental importance. The statement of the geological results capable of being deduced from these investigations is, for greater clearness, reserved for the end. Such of these results as chiefly depend on the validity of the reasonings used in Section III. are presented with some diffidence, owing to the imperfect experimental knowledge we possess respecting the subjects discussed in that section. The diminution of the earth’s mean radius by refrigeration is neglected all through, except where the contrary is specially mentioned.



2016 ◽  
Author(s):  
Thomas Kaminski ◽  
Pierre-Philippe Mathieu

Abstract. The vehicles that fly the satellite into a model of the Earth System are observation operators. They provide the link between the quantities simulated by the model and quantities observed from space, either directly (spectral radiance) or indirectly estimated through a retrieval scheme (bio-geophysical variables). By doing so, observation operators enable modellers to properly compare, evaluate and constrain their models with the model-analogue of the satellite observations. This paper provides the formalism and a few examples of how observation operators can be used, in combination with data assimilation techniques, to better ingest satellite products in a manner consistent with the dynamics of the Earth System expressed by models. It describes communalities and potential synergies between assimilation and classical retrievals. The paper explains how the combination of observation operators and their derivatives (linearisations) form powerful research tools. It introduces a technique called automatic differentiation that greatly simplifies both development and maintenance of derivative code.



1960 ◽  
Vol S7-II (6) ◽  
pp. 801-820
Author(s):  
G. D. Afanasev

Abstract The results of recent studies of elastic wave propagation within the earth are reviewed and different interpretations of the earth's interior which have been proposed, particularly in recent American works, are outlined. The results of these studies and of oceanographic work are incompatible with certain classic theories. The main facts are the differences between the continental and oceanic crust and the relatively recent (Tertiary and Quaternary) age of the great zones of continental subsidence, where a transformation from a continental to an oceanic-type crust is implied. The concept of permanent ocean basins is rejected. Differences between the continental and oceanic crust are considered essentially a function of physical state rather than petrographic composition. Continental zones that have subsided are characterized by greater seismic velocities because of the extra pressure to which they have been subjected in the course of the ages.



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