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In solar–terrestrial physics, there is an open question: does a geomagnetic storm affect earthquakes? We expand research in this direction, analyzing the seismic situation after geomagnetic storms (GMs) accompanied by the precipitation of relativistic electrons from the outer radiation belt to form an additional radiation belt (RB) around lower geomagnetic lines. We consider four widely discussed cases in the literature for long-lived (weeks, months) RBs due to GMs and revealed that the 1/GMs 24 March 1991 with a new RB at L~2.6 was followed by an M7.0 earthquake in Alaska, 30 May 1991, near footprint L = 2.69; the 2/GMs 29 October 2003 (Ap = 204) with new RB first in the slot region at L = 2–2.5 cases followed by an M7.8 earthquake on 17 November 2003 at the Aleutian Islands near footprint L = 2.1, and after forming an RB at L~1.5 which lasted for ~26 months, two mega quakes, M9.1 in 2004 and M8.6 in 2005, occurred at the globe; the 3/GMs 3 September 2012 with a new RB at L= 3.0–3.5 was followed by an M7.8 earthquake in Canada near footprint L = 3.2; and the 4/GMs 21 June 2015 with a new RB at L = 1.5–1.8 was followed by an M6.3 earthquake on 7 September 2015 in New Zealand, near footprint L = 1.58. The obtained results suggest that (1) major earthquakes occur near the footprints of geomagnetic lines filled with relativistic electrons precipitating from the outer radiation belt due to geomagnetic storms, and (2) the time delay between geomagnetic storm onset and earthquake occurrence may vary from several weeks to several months. The results may expand the framework for developing mathematical magnetosphere–ionosphere coupling models. [ABSTRACT FROM AUTHOR]

Abstract: Our analysis of the continuous outgoing long wave earth radiation (OLR) indicates anomalous variations prior to a number of medium to large earthquakes. The most recent analysis of OLR is from the M9.0 Sumatra Andaman Islands mega trust event. We compared the reference fields for December 2001 to 2004 and found OLR anomalous values, >80 W/m2, (2σ) within the epicentral area on Dec 21, 2004, 5 days before the event. We used the NOAA/IR daily (one degree) and monthly (two and half degree) gridded data to differentiate between the global and seasonal variability and the transient local anomalies. The cause of such anomalies is not fully understood; one possible explanation is the existence of thermal outgoing radiation as a result of near ground air ionization and latent heat change due to change of air humidity and temperature. This phenomenon is hypothesized to be part of a relationship between tectonic stresses, electrochemical and thermodynamic processes in the atmosphere and increasing mid IR flux, all part of a family of electromagnetic (EM) phenomena related to earthquake activity. The time scale of the observed variations is a few weeks before the onset of the seismic event. In comparison with several years of data, the observed time-series preceding the earthquake had unusually high OLR. The OLR anomaly corresponds to a large area of ground coverage and coincides with the main epicentral zone. The significance of these observations is explored using data from most recent East Asian earthquake swarm of December 2004 and three other earthquakes. [Copyright &y& Elsevier]

Abstract: Satellite thermal infrared (TIR) imaging data have recorded short-lived anomalies prior to major earthquakes and associations with fault systems. Others have proposed that these signals originate from electromagnetic phenomena associated with pre-seismic processes, causing enhanced IR emissions, that we are calling TIR anomalies. The purpose of this exploratory study is to verify if TIR anomalies can be found in association with known earthquakes by systematically applying satellite data analysis techniques to imagery recorded prior-to and immediately after large earthquakes. Our approach utilizes both a mapping of surface TIR transient fields from polar orbiting satellites and co-registering geosynchronous weather satellites images. The significance of these observations was explored using data sets of recent worldwide strong earthquakes (1999–2003) and the techniques used to capture the trace of TIR anomalies. [Copyright &y& Elsevier]

In a recent paper, we extended a previous study on the solar solar influence to the generation of the March 2012 heatwave in the northeastern USA. In the present study we check the possible relationship of solar activity with the early March 2012 bad weather in northeast Thrace, Greece. To this end, we examined data from various remote sensing instrumentation monitoring the Sun (SDO satellite), Interplanetary space (ACE satellite), the Earth's magnetosphere (Earth-based measurements, NOAA-19 satellite), the top of the clouds (Terra and Aqua satellites), and the near ground atmosphere. Our comparative data analysis suggests that: (i) the winter-like weather (rainfall, fast winds, decreased temperature) in Thrace started on 6 March 2012, the same day as the heatwave started in USA, (ii) during the March 2012 winter-like event in Thrace (6–15 March), the ACE satellite recorded enhanced fluxes of solar energetic particles (SEPs), while SOHO and PAMELA recorded solar protons at very high energies (>500 MeV), (iii) Between 3–31 March, the temperature in Alexandoupoli and the ACE/EPAM solar high energy (1.88–4.70 MeV) proton flux were strongly anticorelated (r = −0.75, p = 0.5). (iv) Thrace experienced particularly intense cyclonic circulation, during periods of magnetic storms on 8–10 and 12–13 March, which occurred after the arrival at ACE of two interplanetary shock waves, on March 8 and March 11, respectively, (v) at the beginning of the two above mentioned periods large atmospheric electric fields were recorded, with values ranging between ~−2000 V/m and ~1800 V/m on 8 March, (vi) the winter-like weather on 8–10 March 2012 occurred after the detection of the main SEP event related with a coronal mass ejection released in interplanetary space as a result of intense solar flare activity observed by SDO on 7 March 2012, (vi) the 8–10 March weather was related with a deep drop of ~63 °C in the cloud top temperature measured by MODIS/Terra, which favors strong precipitation. Finally, we analyzed data from the electric power network in Thrace (~41°N) and we found, for the first time sudden voltage changes of ~3.5 kV in the electric grid in Greece, during the decay phase of the March 2012 storm series. We discuss the winter-like March 2012 event in Thrace regarding the influence of solar cosmic rays on the low troposphere mediated by positive North Atlantic Oscillation (NAO). Finally, we infer that the novel finding of the geomagnetic effects on the electric power grid in Thrace may open a new window into space weather applications research. [ABSTRACT FROM AUTHOR]

We are studying the interaction between gases from the Earth (radon, methane, CO2) that may be associated with pre-seismic activities and the standard atmosphere in order to assess their potential thermodynamic impact. There is an increasing amount of observational evidence that the concentration of these gases increases before major earthquakes. We formulate a hypothesis that an increase in the concentration of these gases triggers a thermodynamic coupling between the lithosphere-atmosphere-ionosphere coupling (LAIC) and is linked to the seismic cycle. Therefore, by studying the LAIC processes we can detect variability in the Earth's gases, which allows us to make an inference about seismic activity. We use radon measurements on the ground installed and coordinated in five different seismically active regions: Southern California, Taiwan, Central Italy, Western Greece and South Eastern Japan. For this study we utilize both NASA and NOAA remote sensing data together with GPS/TEC observations. With Gold and Soter's initial hypothesis of the deep origin of radon and methane (1985), and the fact that the activation of faults leads to an increase in the emanation of gases, we are exploring the feasibility of detecting these gases by measuring their coupling impact on the Earth's atmosphere through ground and space observation. For this analysis we selected 8 large earthquakes from different seismo-tectonics regions: (1) M9.3, Sumatra, Dec 26, 2004; (2) M9.0 Tohoku, Japan, March 11, 2011; (3) and (4) M7.8 and M7.3 Gorkha, Nepal, 2015; (5); M8.2 Tehuantepec, Sept 8, 2017 and; (6) M7.1, Puebla, Mexico, Sept 19, 2017, (7) Mw 6.8 Zakynthos, Greece of Oct 25, 2018 (8) M6.6 Meinong, Taiwan, Feb 6, 2016,. We have found that: (i) radon and atmospheric anomalies have been observed before all of the analyzed events, (ii) large seismic events (M8+) could produce radon anomalies far from the epicenters; and (iii) long lasting seismic swarms could generate temporary elevation of radon levels in the near zone. We examined the possible correlation between magnitude and the spatial size of the earthquake preparation zone (Dobrovolsky- Bowman) in the framework of the LAIC concept. Our data analysis suggests that the pre-earthquake phase follows a general temporal-spatial evolution pattern; in which radon plays a critical role in understanding the LAIC involving different layers of the ionosphere, atmosphere and lithosphere. Pre-Earthquake Processes: A Multi-disciplinary Approach to Earthquake Prediction Studies, AGU/Wiley, 2018, 385 pp, (Ed's: Ouzounov D., S. Pulinets, K.Hattori, P.Taylor) The Possibility of Earthquake Forecasting: Learning from nature, Institute of Physics Books, IOP Publishing, Dec 2018, 168pp (S. Pulinets and D. Ouzounov) [ABSTRACT FROM AUTHOR]

We present an interdisciplinary study of observations of pre-earthquake processes associated with major earthquakes based on integrating space and ground observations. Recent large magnitude earthquakes in Asia, Europe and Americas have emphasized the various observations of multiple types of pre-earthquake signals recorded either on the ground or from space. We are studying the general temporal-spatial and evolution patterns of these pre-earthquake signals and their significance as a function of retrospective and prospective testing. We formulate a concept that an increase in the concentration of geo gases (radon, methane, CO2) triggered a lithosphere-atmosphere-ionosphere coupling (LAIC) and is linked to the seismic cycle. Therefore, by studying the LAIC processes we can detect transitional coupling in geospheres, which allows us to make an inference about seismic activity. The Multi Sensor Networking Analysis (MSNA) is our method for validation and is based on a joint analysis of several physical parameters: Satellite transient infrared radiation anomalies (STIR), electron concentration in the ionosphere (GPS/TEC), geogas/radon activities, air temperature/humidity patterns, that were found to be associated with earthquakes. The MSNA is based on multi-disciplinary approach, because it is widely recognized that our understanding of geophysical processes is improved by integration of studies from seismology, geochemistry, geomagnetism, atmospheric science and geology. To quantify our validation, we start computing Molchan Error Diagram (MED) retrospectively and prospectively for anomalous ionospheric/atmospheric signals. Our validation processes included retrospective analysis since 2004 of major earthquakes preformed over the regions with high seismicity- Taiwan, Japan, China California, Mediterranean, Mexico, Chile and Kamchatka and prospective testing for potential for M7+ events since 2013 worldwide and a special test for M6+ over the Japanese region. Still an average false alarm ratio of 25% exists, but the method has the potential for improvements, with more research. Our results suggest that: (1) Pre-earthquake atmospheric/ionospheric signals follow the LAIC proposed temporal-spatial evolution pattern (with 1-30 days' time-lag), which has been seen for most of large earthquakes worldwide; (2) Testing of pre-earthquake signals shell continue moving from single towards multi-parameter testing; and (3) MED test results indicate that pre-earthquake atmospheric anomalies could provide short-term predictive information in the tested regions. A detail summary of this approach been published in AGU/Wiley and Institute of Physics monograph series.Pre-Earthquake Processes: A Multi-disciplinary Approach to Earthquake Prediction Studies, AGU/Wiley, 2018, 385 pp, (Ed's: Ouzounov D., S. Pulinets, K.Hattori, P.Taylor) The Possibility of Earthquake Forecasting: Learning from nature, Institute of Physics Books, IOP Publishing, Dec 2018, 168pp (S. Pulinets and D. Ouzounov) [ABSTRACT FROM AUTHOR]

This contribution is addressed to an introductive university course on the correlation existing between radon emission and earthquakes processes held following a flipped-class approach where students receive didactic materials prior to face-to-face lessons. This research was initially started to investigate the real correlation between Radon emission from the Earth and the occurrence of strong earthquakes by using measurements of hourly Radon flow variation. During quiet seismogenic conditions, we observe an unvarying level of Radon emission in the air. Before a strong earthquake, substantial variations of Radon (222Rn) concentration have been observed in the air, probably because of the increase of thermodynamic energy inside the Earth. The physical processes affecting earthquakes are still not fully understood; therefore, we are interested in investigating a wide variety of signals observed before an earthquake, ranging from chemical, electric, and magnetic variations. The goal is to be able to estimate the earthquake magnitude, timing also location in advance with a good approximation. The experimental observation and research studies were carried out by G. Giuliani Permanent Foundation since 2002 in Abruzzo. The innovative methodology of observations with Gamma detectors allowed us to reveal a close correlation between the different physical phenomena during the preparation phase of strong earthquakes. We master the methodology of measuring the hourly flow of 222Rn gas decay, which provides a good correlation with the occurrence of strong earthquakes. To advance the reliability of our assessment, we added more parameters to our observations, such as magnetic and RF. The joint analysis advances our understanding of the processes underlying the earthquake occurrence. The experimental observation of Radon has been tested for more than a decade in the Abruzzo region. The initial results provided the baseline of reliable correlation between radon variations and earthquakes that could be used as an alert mechanism for the forthcoming seismic events. The multiparametric approach of detecting pre-earthquakes signals provided the robustness in detecting the earthquake preparation phase. There are no doubts that by expanding the network of gamma sensors, we achieve much better signal detection, which is critical for the better spatial correlation of Radon variations with the earthquake processes. [ABSTRACT FROM AUTHOR]

Taking the Madoi MS 7.4 earthquake of 21 May 2021 as an example, this paper proposes using time series prediction models to predict the outgoing long-wave radiation (OLR) anomalies and study short-term pre-earthquake signals. Five time series prediction models, including autoregressive integrated moving average (ARIMA) and long short-term memory (LSTM), were trained with the OLR time series data of the aseismic moments in the 5° × 5° spatial range around the epicenter. The model with the highest prediction accuracy was selected to retrospectively predict the OLR values during the aseismic period and before the earthquake in the area. It was found, by comparing the predicted time series values with the actual time series value, that the similarity indexes of the two time series before the earthquake were lower than the index of the aseismic period, indicating that the predicted time series before the earthquake significantly differed from the actual time series. Meanwhile, the temporal and spatial distribution characteristics of the anomalies in the 90 days before the earthquake were analyzed with a 95% confidence interval as the criterion of the anomalies, and the following was found: out of 25 grids, 18 grids showed anomalies—the anomalies of the different grids appeared on similar dates, and the anomalies of high values appeared centrally at the time of the earthquake, which supports the hypothesis that pre-earthquake signals may be associated with the earthquake. [ABSTRACT FROM AUTHOR]

Our observations indicate a characteristic pattern in the long-term variation of soil radon concentrations, which seems to be consistent with the expected variation of regional stress in relation to seismicity. However, it seems that the major changes in radon level begin before the rock rapture, i.e. before the earthquake occurs. These conclusions have emerged after long-term observations with continuous and thorough real-time gamma-radiation monitoring in the seismically active area of the Gulf of Corinth, Greece. The recordings acquired close to a hot spring were of very high quality, implying that the deep hydraulic flow can possibly play a key role in the pre-earthquake variation of radon level. We were able to observe outstanding examples of radon level variations before significant seismic events in the Gulf of Corinth that cannot be attributed to other external factors such as atmospheric phenomena. [ABSTRACT FROM AUTHOR]

We re-examined the knowledge on the relationships between fauna and forest management in Italy. We focused our attention on Vertebrates, including small mammals (Rodents and Soricomorphs), bats, birds, reptiles and amphibians, and on carabid and saproxylic beetles. We found that nearly all groups respond in accordance with Angelstam's scheme of the traditional forestry cycle, with open habitat specialists followed by generalists and forest specialists when pristine conditions have been attained, though with some differences for some taxa. In all groups, some forest "superspecialists" or old growth indicators could be found, in (sub)Mediterranean forests some carabid beetles could be defined as "dendrophilous," i.e. associated with the presence of old trees. Poplar plantations are poor substitutes for native forests, as well as exotic conifers. We propose a model for an ideal forest structure that may efficiently preserve the faunal components, at the microscale level this coincides with the structure of an unmanaged old growth forest stand, marked also by a deep and humus-rich soil layer. Some caveats at the landscape scale have dealt with in relation to the size of the designed area, in order to avoid fragmentation effects. A sustainable harvesting scheme has indicated in the "systemic silviculture" proposed by Ciancio and other scientists. [ABSTRACT FROM AUTHOR]

The paper provides a comparative analysis of precursory phenomena in the ionosphere and atmosphere for two strong earthquakes of the same magnitude M7.1 that happened in the same region (North-East from Los Angeles) within a time span of 20 years, the Hector Mine and Ridgecrest earthquakes. Regardless of the similarity of their location (South-Eastern California, near 160 km one from another), there was one essential difference: the Hector Mine earthquake happened during geomagnetically disturbed conditions (essential in the sense of ionospheric precursors identification). In contrast, the quiet geomagnetic conditions characterized the period around the time of the Ridgecrest earthquake. The Hector mine earthquake happened in the middle of the rising phase of the 23-rd solar cycle characterized by high solar activity, while the Ridgecrest earthquake happened by the very end of the 24th cycle under very low solar activity conditions. We provide a comprehensive multi-factor analysis, determine the precursory period for both earthquakes and demonstrate the close similarity of ionospheric precursors. Unlike the majority of papers dealing with earthquake precursor identification based on the "abnormality" of observed time-series mainly determined by amplitude difference between "normal" (usually climatic) behavior and "abnormal" behavior with amplitudes exceeding some pre-established threshold, we used the technique of cognitive recognition of the precursors based on the physical mechanisms of their generation and the morphology of their behavior during the precursory period. These permits to uniquely identify precursors even in conditions of disturbed environment as it was around the time of the Hector Mine earthquake. We demonstrate the close similarity of precursors' development for both events. The leading time of precursor appearance for the same region and similar magnitude was identical. For the Hector Mine it was 11 October 1999—5 days in advance—and for 2019 Ridgecrest it was 28 June—7 days before the mainshock and five days before the strongest foreshock. [ABSTRACT FROM AUTHOR]

From the combined use of independent observations, the major improvements of the quality (in terms of reliability and space-time precision) of short-term seismic hazard estimation, are expected. Among the others, satellite observations can guarantee the global coverage and temporal continuity required in order to dynamically update seismic risk at a large scale. Several satellite techniques have already demonstrated the predictive potential of specific tropospheric (e.g. Outgoing Longwave and Thermal InfraRed Radiation) and ionospheric (Total Electronic Content, Plasma Density, etc.) parameters. Long-term correlation analyses have been performed in order to quantitatively characterize such a potential together with the main limits (particularly in term of false positive rates) associated to each of them. New (after the precursory DEMETER mission) dedicated satellite missions have been recently started (like the China Seismo-Electromagnetic Satellite, CSES; FORMOSAT-5/Advanced Ionospheric Probe, F5/AIP), which promise, together with a continuously increasing network of ground-based observatories, to further complement already existing satellite systems. This paper present, in the case of strong earthquakes occurred in Indonesia in the August-September 2018, a first, retrospective, experiment of short-term seismic hazard assessment based on the joint analysis of independent consolidated and new (mostly from CSES) satellite EM observations. The added value of their combined (vs individual) use will be evaluated both in terms of reliability of the forecast and improvement of probability gains. [ABSTRACT FROM AUTHOR]

A gamma-ray station has been established recently along the Longitudinal Valley in eastern Taiwan, which is a suture zone with NNE-striking on the boundary between Eurasia plate and Philippine Sea plate. Stresses arise in the crust in accordance with crustal deformations due to plate motions and geodynamic processes. Gamma-ray emission associated with the radioactive decay of radon, which is discharged into surface from deep source area, is continuously recorded in the station. Fluctuations of gamma-ray data are found to show a clear inverse correlation with atmospheric temperature. Based on the linear regression method, possible temperature effects can be removed and the corrected data can be obtained. Anomalous variations in the gamma-ray counting rate may appear as precursors a few days before some local earthquakes in eastern Taiwan. It is noted that there are two significant increases in the gamma-ray counting rate during the periods from March 20 to 26 and from April 22 to May 1, 2014. These increases are observed about one week before two earthquake swarms from March 26 to 27 and from May 3 to 5, 2014. Furthermore, a progressive anomaly with a continuous increase (∼8%) in gamma-ray count was recorded two weeks before the Fanglin Earthquake ( M L = 5.9, May 21, 2014) occurring in the Longitudinal Valley area. A continuous monitoring on the gamma-ray data can improve our understanding of the possible relationship between the observed gamma-ray variations and the earthquakes in the study area. [ABSTRACT FROM AUTHOR]

The largest possible earthquake magnitude based on geographical characteristics for a selected return period is required in earthquake engineering, disaster management, and insurance. Ground-based observations combined with statistical analyses may offer new insights into earthquake prediction. In this study, to investigate the seismic characteristics of different geographical regions in detail, clustering was used to provide earthquake zoning for Mainland China based on the geographical features of earthquake events. In combination with geospatial methods, statistical extreme value models and the right-truncated Gutenberg–Richter model were used to analyze the earthquake magnitudes of Mainland China under both clustering and non-clustering. The results demonstrate that the right-truncated peaks-over-threshold model is the relatively optimal statistical model compared with classical extreme value theory models, the estimated return level of which is very close to that of the geographical-based right-truncated Gutenberg–Richter model. Such statistical models can provide a quantitative analysis of the probability of future earthquake risks in China, and geographical information can be integrated to locate the earthquake risk accurately. [ABSTRACT FROM AUTHOR]

In this work, we assessed the possible relation of ionospheric perturbations observed by Detection of Electro-Magnetic Emissions Transmitted from Earthquake Regions (DEMETER), Global Positioning System total electron content (GPS TEC), National Oceanic and Atmospheric Administration (NOAA)-derived outgoing longwave-Earth radiation (OLR), and atmospheric chemical potential (ACP) measurements, with volcanic and Saharan dust events identified by ground and satellite-based medium infrared/thermal infrared (MIR/TIR) observations. The results indicated that the Mt. Etna (Italy) volcanic activity of 2006 was probably responsible for the ionospheric perturbations revealed by DEMETER on 4 November and 6 December and by GPS TEC observations on 4 November and 12 December. This activity also affected the OLR (on 26 October; 6 and 23 November; and 2, 6, and 14 December) and ACP (on 31 October–1 November) analyses. Similarly, two massive Saharan dust episodes, detected by Robust Satellite Techniques (RST) using Spinning Enhanced Visible and Infrared Imager (SEVIRI) optical data, probably caused the ionospheric anomalies recorded, based on DEMETER and GPS TEC observations, over the Mediterranean basin in May 2008. The study confirmed the perturbing effects of volcanic and dust events on tropospheric and ionospheric parameters. Further, it demonstrated the advantages of using independent satellite observations to investigate atmospheric phenomena, which may not always be well documented. The impact of this increased detection capacity in reducing false positives, in the framework of a short-term seismic hazard forecast based on the study of ionospheric and tropospheric anomalies, is also addressed. [ABSTRACT FROM AUTHOR]

We present the first stage of the interdisciplinary project called "IONOTERRA" on the experimental range creation in the vicinity of Vrancea seismic zone. It is interdisciplinary project using the multiparameter monitoring approach to reveal the precursory period for strong earthquakes in Vrancea zone where the leading role is assigned to the ionospheric precursors. The data of ionospheric parameters monitoring will be collected using several techniques: vertical and oblique ground-based ionospheric sounding, GPS TEC measurements of individual GPS receivers and Global Ionospheric Maps (GIM) technology, spaceborn instrumentation using the local plasma probes on CSES-1, SWARM and COSMIC satellites, and topside sounding from Russian IONOSONDE constellation. The experimental range will be organized at the territory of Republlic of Moldova and will include the mobile geophysical observatory to measure in addition to ionospheric measurements the gamma spectrometer for radon activity monitoring, vertical electric field measurements, electromagnetic emissions in VLF and VHF bands, meteorological parameters (air temperature and humidity) and aerosol optical thickness. Together with ground-based meteorological meausrements the satellite data on local thermal anomalies will be used. It is double purpose project: it will validate the physical concept of LAIC model, and simultaneously will develop the practical applications for automatic detection of the short-term earthquake precursors and to make decision on the precursory period initiation. The project will unite efforts of three groups of scientists having years of experience on ground-based and spaceborn monitoring of the short-term earthquake precursors and the Lithosphere-Atmosphere-Ionosphere Coupling Model development. Some results of the Vrancea zone earthquake precursors monitoring registered by different techniques will be demonstrated. [ABSTRACT FROM AUTHOR]