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We present a study on temporal and spatial characteristics of Thermal Radiation anomalies (TRA) and ionospheric total electron content (TEC) pre-earthquake abnormalities associated with the occurred in 2022 “anniversary” earthquakes. “Anniversary” is a quake occurring on the same date and following the years after the main earthquake, plus or minus several days.We studied eleven large earthquakes in four regions: i/Japan: M7.3 of 03.16.2022 and M9.0 of 03.11.2011 East Coast Honshu; ii/Mexico: M7.6 of 09.19.2022 Michoacan; M7.1 of 09.19.2017 Puebla and M8.0 of 09.19.1985 Mexico City;/iii Chile: M5.7 02.28.2022 Bio-Bio and M8.8 02.27.2010 Maule and /iv Taiwan: M6.9 of 09.18.2022 Taitung and M7.7 of 09.21.1999 Chi-Chil and M6.7 of 03.22.2022 Taitung and M6 of 03.27.2013 Nantou earthquake.We analyzed for TRA and TEC anomalies concerning the earthquake preparation zone (EPZ). For EPZ estimates, we use Dobrovolsky et al. (1979), and Bowman et al. (1998) estimates where the EPZ radius scales exponentially with earthquake magnitude, especially from Mw ≥ 6.0 onwards, and gives an extended coverage at larger magnitudes to examine TRA and ionospheric TEC anomalies. The main goals of this study were: 1/to understand the seismotectonic conditions that preceded the earthquake re-occurrence in the same place and on the same day(s): 2/ to perform a validation study about pre-earthquake signal occurrences in the same atmospheric and solar-geophysical conditions and 3/ to understand the potential triggering mechanism. Our preliminary results show synergetic coordination between the appearance of pre-earthquake transients’ effects in the atmosphere and ionosphere (with a short time lag, from hours up to a few days). The spatial characteristics of pre-earthquake anomalies were associated with the large area but inside the preparation region estimated by Dobrovolsky-Bowman. The pre-earthquake nature of the signals in the atmosphere and ionosphere was revealed by simultaneous analysis of satellite, GPS/TEC, and Satellite Earth observations. The “anniversary” events are recognized with common pre-earthquake transient re-occurrence patterns in the atmosphere/ionosphere within EPZ, scaled to the extent of the earthquake magnitude.

International audience; This paper explores multi-instrument space-borne observations in order to validate physical concepts of Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) in relation to a selection of major seismic events. In this study we apply some validated techniques to observations in order to identify atmospheric and ionospheric precursors associated with some of recent most destructive earthquakes: M8.6 of March 28, 2005 and M8.5 of Sept. 12, 2007 in Sumatra, and M7.9 of May 12, 2008 in Wenchuan, China. New investigations are also presented concerning these three earthquakes and for the M7.2 of March 2008 in the Xinjiang-Xizang border region, China (the Yutian earthquake). It concerns the ionospheric density, the Global Ionospheric Maps (GIM) of the Total Electron Content (TEC), the Thermal Infra-Red (TIR) anomalies, and the Outgoing Longwave Radiation (OLR) data. It is shown that all these anomalies are identified as short-term precursors, which can be explained by the LAIC concept proposed in [S. Pulinets, D. Ouzounov, J. Asian Earth Sci. 41, 371 (2011)].

The 28 September 2018 magnitude Mw7.8 Palu, Indonesia earthquake (0.178° S, 119.840° E, depth 13 km) occurred at 10:02 UTC. The major earthquake triggered catastrophic liquefaction, landslides, and a near-field tsunami. The ionospheric total electron content (TEC) derived from records of 5 ground-based global navigation satellite system (GNSS) receivers is employed to detect tsunami traveling ionospheric disturbances (TTIDs). In total, 15 TTIDs have been detected. The ray-tracing and beamforming techniques are then used to find the TTID source location. The bootstrap method is applied in order to further explore the possible location of the tsunami source based on results of the two techniques, which show the beamforming technique has a slightly better performance on finding possible locations of the tsunami source. Meanwhile, the circle method is employed to examine tsunami signatures of the sea-surface height and video records, and find possible tsunami origin locations. The coincidence of the TTID source location and the tsunami location shows that the ionospheric TEC recorded by local ground-based GNSS receivers can be used to confirm the tsunami occurrence, find the tsunami location, and support the tsunami early warning.

Recently, there are many papers on electromagnetic pre-earthquake phenomena such as geomagnetic, ionospheric, and atmospheric anomalous changes. Ionospheric anomaly preceding large earthquakes is one of the most promising phenomena. Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) model has been proposed to explain these phenomena. In this study, to evaluate the possibility of chemical channel of LAIC by observation, we have installed sensors for atmospheric electric field, atmospheric ion concentration, atmospheric Rn concentration, soil radon Rn concentration (SRC), and weather elements at Asahi station, Boso, Japan. Since the atmospheric electricity parameters are very much influenced by weather factors, it is necessary to remove these effects as much as possible. In this aim, we apply the MSSA (Multi-channel Singular Spectral Analysis) to remove these influences from the variation of GRC and estimate the soil Rn flux (SRF). We investigated the correlations (1) between SRF and precipitation and (2) between SRF and the local seismic activity around Asahi station. The preliminary results show that SRF was significantly increased by heavy precipitations of 20 mm or more in total for 2 hours. We proposed two types of models, a rainwater load model and a rainwater infiltration model, and it is appropriate for both models to work and (2) between SRF and local seismicity within an epicenter distance of 50 km from the station.

We are studying the transient lunar phenomena (TLP) as an indicator of lunar tectonics. Seismic events can be used as a direct indicator of some tectonic activities of the planets. The Moon-Earth gravitational interaction has been studied extensively as a triggering mechanism for earthquakes. However, this is a controversial topic. Our present study investigated the reverse Earth-Moon interaction concerning the TLP activities. The lunar outgassing is potentially the leading source of TLP activities. We have investigated both Earth venting and earthquakes and have found that radon was frequently activated before significant seismic events due to the Moon-Sun interaction with the Earth (Ouzounov et al., 2018). Earthquake lights, an associated phenomenon reported before some major earthquakes, are analogous to TLP activities on the Moon. In 1972, N. Kozyrev suggested a possible lunar response to the significant seismic events on the Earth. To understand whether TLP's have any possible connection with earthquakes, we performed a statistical review between significant earthquakes, using the NEIC catalog and TLPs during 1907-1977, for four lunar areas: Aristarchus, Plato, Gassendi, and Alphonsus. We used TLP catalogs published by Middlehurst et al. 1968; Cameron, 2006; and Crotts, 2008. Our results revealed a causal relationship between significant earthquakes and TLP events. However, the strength of this relationship varies from the location and depth of the earthquakes. Deformation on the Moon triggers the degassing process, and TLPs are indicators for those underlying activities. Our work can provide new information about the origin of TLP and the existence of a possible relationship between the tectonic processes of Earth and the Moon. The Earth causes crustal tides on the Moon, and the Moon produces tides on the Earth.

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.

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.

The forefront of science now is in bridging fields and making connections across different disciplines, challenging our current understanding of the Earth's changes and overall state. Some of the most challenging science questions now have to do with warnings for significant geohazards and Earth-Space systems' response to climate variability affecting adaptation processes, such as geosphere changes due to climate change and resultant strategies. In recent years, the study of pre-earthquake processes has led for example to developing the lithosphere-atmosphere-ionosphere-coupling concept. This in turn provides new information about the Earth's energy balance (Pulinets and Ouzounov, 2011). From space-born NASA and NOAA Earth observation of atmospheric conditions, we have shown the consistent occurrence of radiative emission anomalies in the atmosphere near or over regions of earthquakes, volcanoes, and geothermal fluxes. Our assessment shows that the latent heat released before major earthquakes is larger than the seismic energy released during the quake (Ouzounov et al., 2018). We find that the associated pre-earthquake phenomena for large events may create an additional thermodynamic contribution in the atmosphere and impact on climate, caused by sources of Earth de-gassing in the lithosphere and followed by ionization processes. Because of these findings, we start exploring major global geodynamics activities and their impact on atmospheric processes and climate through the geosphere coupling channels as a potential forward process of interaction between geohazards and climate adaptation. The reverse mechanism of climate adaptation's impact on geohazards is based on the initial idea that climate adaptation could force additional geohazards activities (McGuire, 2010). The removal of ice sheets may somehow or likely have permitted the release of stresses that had accumulated on previously confined faults, triggering earthquakes in the US, Canada, and Europe. How realistically is it to expect a change in the existing earthquake patterns in Europe, the USA, and Canada during climate change processes? It is plausible, but we do not yet know the answer. Our goal is to explore the coupling between geohazards processes and climate change processes through the lithosphere-atmosphere framework, focusing on dynamic environments, exhibiting a change in physical and thermodynamics processes over relatively small-time scales.

There are many reports on electromagnetic pre-earthquake phenomena such as geomagnetic, ionospheric, and atmospheric anomalous changes. Ionospheric anomaly preceding large earthquakes is one of the most promising phenomena. Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) model has been proposed to explain these phenomena. In this study, to evaluate the possibility of chemical channel of LAIC by observation, we have installed sensors for atmospheric electric field, atmospheric ion concentration, atmospheric Rn concentration, underground Rn concentration (GRC), and weather elements at Asahi station, Boso, Japan. Since the atmospheric electricity parameters are very much influenced by weather factors, it is necessary to remove these effects as much as possible. In this aim, we apply the MSSA (Multi-channel Singular Spectral Analysis) to remove these influences from the variation of GRC and estimate the underground Rn flux (GRF). We investigated the correlations (1) between GRF and precipitation and (2) between GRF and the local seismic activity around Asahi station. The preliminary results show that there is a tendency of correlation (1) between GRF and heavy rain and (2) between GRF and local seismicity within an epicenter distance of 50 km from the station.

We are presenting the latest results of multi-sensor observations of short-term pre-earthquake phenomena preceding significant earthquakes. We study satellite thermal infrared radiation (OLR) anomalous signals in association with three major earthquakes, which occurred in Xinjiang province, China at different periods M7.3 of 02.12.2014; M6.2 of 08.12.2012; and M7.2 of 03.20.2008. We systematically apply multi-sensor satellite thermal data and ground temperature /humidity and estimates of the atmospheric chemical potential (ACP) parameter. Data analyses include NOAA NPOESS, the Chinese geostationary satellite FY-2D, and in-situ hourly NOAA data from the Hotan weather station. In all three cases, we detected atmospheric satellite OLR anomalies developed near the epicenter area and ACP increases (significant change for 2008 and 2014, weak for 2012) over the major Altyn Tagh fault lines within 10-20 days before the earthquake event. These findings demonstrate the occurrence and reoccurrence of transient variations of these parameters, implying their connection with the earthquake preparation process.

This paper proposes an analysis method, using the National Oceanic and Atmospheric Administration satellite data, to trace variations in outgoing longwave radiation (OLR) for finding the precursors of earthquakes. The significance of these observations is investigated using data sets of recent M ≥ 6.0 earthquakes around the Taiwan area from 2009 to 2019. We suggest that the precursory signal could be an EIndex anomaly (EA) in the form of substantial thermal releases distributed near the epicenter. The consecutive appearances of OLR EAs are observed as precursors two to fifteen days before significant earthquakes, and we refer to this as a pre-earthquake OLR EIndex anomaly (POEA). We interpret these thermal sources as possibly originating from electromagnetics together with gas emissions associated with pre-seismic processes. This study highlights the potential of OLR anomalous changes in earthquake precursor studies, at least in the Taiwan region.

The science community is still looking for pre-earthquake indicators of major seismic events in order to minimize the loss of human life. Recent advances in satellite technology have helped to increase the scientific understanding of the nature of pre-earthquake phenomena in the atmosphere and their relationship with transitional thermal anomalies. It was realized that the thermal heat fluxes over areas of earthquake preparation are a result of air ionization by Rn222, its isotopes and progenies and consequent water vapor condensation on newly formed ions. Latent heat (LH) is released as a result of this process and leads to the formation of local thermal radiation anomalies (TRA) known as outgoing longwave radiation (OLR). We recorded data from the most recent major earthquakes in California (2014) Nepal (2015) that allowed us to summaries TRA’s main morphological features. It was also established that the TRA is part of a more complex chain of the short - term earthquake precursors, which are explained within the framework of a Lithosphere-Atmosphere-Ionosphere Coupling (LAIC) model.

We present a multi parameters analysis of satellite and ground data that revealed a transient phenomenon in the atmosphere before the M6.4 earthquake in Albania on Nov 26, 2019. The observational methodology consists of data from five physical measurements: (1) Satellite Thermal Anomalies (data obtained from NOAA) on the top of the atmosphere; (2); Atmospheric chemical potential (ACP) obtained from the NASA assimilation models; (3); Measurement of Radon level variations (two gamma stations in Central Italy); (4) VHF propagation in the lower atmosphere from ground observations and; (5) Electron density variations in the ionosphere via GPS Total Electron Content (GPS/TEC)On Nov 21, 2019 our NOAA STA daily analysis over the Mediterranean detected a strong abnormal pattern between Italy and Albania. We estimated that a possible earthquake could occur in the Adriatic Sea between Italy and Albania with M5.5+ and start cross parameter validation with other observations. On Nov 26 an earthquake occurred near STA anomaly of Nov 21. The epicenter of the M6.4 earthquake in Albania is situated about 500 kilometers NE of the two-radon monitoring stations in Central Italy. Real-time hourly data show an increase in both sensors on Nov 20 (6 days before the M6.4 of Nov 26, 2019). From the satellite data these increases in radon coincide with an increase in the atmospheric chemical potential (on Nov 21), measured near the epicentral area. VHF data observed from two stations located 300 km from the epicenter in Northeast Bulgaria, indicated an intensity modulation about 90 hours (3.5 days) before the mainshock. The GPS/Total Electron Content data indicated an increase of electron concentration in the ionosphere 1-2 days before the M6.4 earthquake. We observed a synergetic abnormal response from ground and satellite data, although the ground data (radon and VHF) sensors were far from the epicenter (500 and 300 km, respectively). Starting six days before the M6.4 Nov 26 earthquake, the anomalous patterns were inside the Dobrovolsky-Bowman area of preparation. We examined the possible correlation between different pre-earthquake anomalies and the relationship between magnitude and the spatial size of the preparation zone in the framework of the Lithosphere -Atmosphere -Ionosphere Coupling (LAIC) concept.

The paper describes an approach that allows, basing on the data of multiparameter monitoring of atmospheric and ionospheric parameters and using ground-based and satellite measurements, to select from the data stream a time interval indicating the beginning of the final stage of earthquake preparation, and finally using intelligent data processing to carry out a short-term forecast for a time interval of 2 weeks to 1 day before the main shock. Based on the physical model of the lithosphere-atmospheric-ionospheric coupling, the precursors are selected, the ensemble of which is observed only during the precursory periods, and their identification is based on morphological features determined by the physical mechanism of their generation, and not on amplitude selection based on statistical data processing. Basing on the developed maquette of the automatic processing service, the possibility of real-time monitoring of the situation in a seismically active region will be demonstrated using the territory of the Kamchatka region and the Kuril Islands.

An experimental study of the phase and amplitude observations of sub‐ionospheric very low and low frequency (VLF/LF) signals is performed to analyze the response of the lower ionosphere during the 21 August 2017 total solar eclipse in the United States of America. Three different sub‐ionospheric wave paths are investigated. The length of the paths varies from 2,200 to 6,400 km, and the signal frequencies are 21.4, 25.2, and 40.75 kHz. The two paths cross the region of the total eclipse, and the third path is in the region of 40–60% of obscuration. None of the signals reveal any noticeable amplitude changes during the eclipse, while negative phase anomalies (from −33° to −95°) are detected for all three paths. It is shown that the effective reflection height of the ionosphere in low and middle latitudes is increased by about 3–5 km during the eclipse. Estimation of the electron density change in the lower ionosphere caused by the eclipse, using linear recombination law, shows that the average decrease is by 2.1 to 4.5 times.

The experience of short-term forecasting of Kamchatka earthquakes based on complex well measurements at the Petropavlovsk-Kamchatsky geody-namic polygon (PGP) shows that, as a rule, the preparation of strong Kamchatka earthquakes is fairly reliable in the medium-term time scale (months or years be-fore the earthquake). However the determination of the stage beginning imme-diately preceding an earthquake (weeks or days before the main event) is a very difficult task. At present time, the solution of this problem is largely associated with the involvement in the preparation of forecast conclusions of data from continuous monitoring of the ionosphere, carried out by ground-based means of vertical radiosonding and measurements of total electronic content (TEC) using the global navigation satellite system GLONASS and GPS. This is due to the fact that significant changes in a number of ionospheric parameters occur mainly 1-5 days before the Kamchatka earthquakes. The results of the compar-ison of the data of daily monitoring of the ionosphere, including information on TEC, with the data integrated downhole measurements showed a rather high correlation of occurrence of anomalies in the ionosphere before strong earth-quakes with changes in the complex parameters in borehole measurements. As one example, the report presents the results of ionospheric and borehole monitoring obtained in the time neighborhood of the strong (MW= 7.5) the earth-quake that occurred on March 25, 2020 in the area of the Northern Kurils. The results show a high correlation between changes in the specific electrical resis-tivity of the Geospace in the area of the PGP with variations in the TEC and the formation of a number of other anomalies in the ionosphere a few days be-fore the earthquake. These results indicate that it is possible to determine fairly reliably the beginning of the final stage of preparation for a strong earthquake. Currently, methods based on atmospheric parameters monitoring are used quite successfully for predictive estimates of the epicenter and magnitude of an earth-quake: the method of chemical potential corrections for measurements at an altitude of ∼ 100 m, as well as data from measurements of outgoing long-wave infrared radiation (OLR) at the level of the upper edge of clouds (heights of 10 -15 km).

Spatial and temporal variations of total column of CH 4 and CO (TotCH 4 and TotCO) associated with the 12 May 2008 Wenchuan and 20 April 2013 Lushan earthquakes in western Sichuan, China were investigated using satellite data from AQUA AIRS in order to understand the lithospheric and atmospheric interactions during the seismic activity. The Wenchuan M S 8.0 and Lushan M S 7.0 earthquakes occurred in the Longmenshan fault zone. It was observed that large amounts of gases emitted from the earth's crust into the atmosphere before, during and after the earthquakes. The anomalies of TotCH 4 and TotCO occurred along the fault zone, and the peak values were found at the intersection areas where the crust stress approached the maximum. Furthermore, temporal anomalies of TotCH 4 and TotCO occurred during and after the Wenchuan earthquake, but 3 months before the Lushan earthquake. The anomalies related to the Lushan earthquake could be partially attributed to the Wenchuan earthquake because of the seismotectonic changes and fractures in the crust produced by the Wenchuan earthquake.