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A digital low power pulse compressed ionosonde was developed at the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy. The aim of this Advanced Ionospheric Sounder, AIS-INGV, is to reduce the transmitted power and, consequently, weight, size, power consumption and hardware complexity. To compensate the power reduction the most advanced HF radar techniques such as the pulse compression and a phase coherent integration are used. The ionosonde is completely programmable and a PC supports the data acquisition, control, storage and on-line processing. The first prototype was installed at Gibilmanna Ionospheric Observatory (Sicily), an interesting location in the center of Mediterranean area. The new ionosonde will contribute to ionospheric database and real time knowledge of South European ionospheric conditions for space weather applications. In this work the first results (ionograms and autoscaled characteristics) are presented and briefly discussed.

A new digital ionosonde called AIS-INGV (Advanced Ionospheric Sounder) was designed both for research and for routine service of HF radio wave propagation forecast. Nearly the entire system was developed in the Laboratorio di Geofisica Ambientale at the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome. It exploits advanced techniques for signal analysis, recent technological devices and PC resources. This paper describes design concepts and performance of the new ionosonde.

The Italian Ionospheric Antarctic Observatory of Terra Nova Bay (74.70S, 164.11E) was recently equipped with the AIS-INGV ionosonde developed at the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, (Italy). This paper aims to describe briefly which are the main characteristics of the instrument and show the good quality and reliability of the recorded ionograms.

The ionosonde is a system which exploits the radar technique: it applies electromagnetic waves with variable frequency in the HF band to measure the ionospheric layers electron density, height and other parameters. This paper is a technical report on the new digital ionosonde (AIS-INGV), which was designed both for research purposes and for the routine service of the HF radiowave propagation forecast. It has been developed almost completely within the Laboratorio di Geofisica Ambientale (LGA) at the Istituto Nazionale di Geofisica e Vulcanologia (INGV). It exploits advanced techniques for the signal analysis, recent technological devices and PC resources. The report is divided into two parts; the first is a general description of the design development, the second is a more detailed description of the blocks and circuits actually built and tested, directed to a specialist reader.

www.earth-prints.org aims to satisfy the increasing demand of fast, up-to-date, easy-accessible, and free-of-charge sources of information in all branches of Geosciences. It allows earth scientists to deposit electronic documents into its collections and to index them by subjects and keywords. Earth-prints provides a time-stamp to all deposited materials to insure precedence rights to original ideas and scientific results. It deals with copyright issues through Creative Common standards that offer a wide variety of licenses. All deposited material is made immediately available to the public. Subscribers will be sent a daily newsletter according to the topics they have signed in. The archive has a three-level hierarchical structure. The top level includes Atmosphere, Cryosphere, Hydrosphere, Solid Earth, and General. It then branches into several disciplines within the other two levels. Different collections take in different kinds of material, such as pre-prints, oral presentations, extended abstracts, published papers, conference papers, books and book chapters, posters, and Web products and databases. Earth-Prints main language is English but it accepts documents in other languages also, giving visibility to data and studies at local scale that are indeed of general interests. An abstract in English is always required. We will present a virtual tour into the many features of Earth-prints to provide all its potential users with an easy acquaintance of the system and make them explore its capabilities. Although the archive is based on latest information technology it requires no specific knowledge to be used because it manages all procedures for access, navigation, upload of documents and information retrieval through a user-friendly interface. What is the limit of open archive development? We think that the one and only limit of open archives is the eagerness of its users to share information and knowledge.

We set up a computational tool to numerically model static and quasi-static deformation generated by faulting sources embedded in plane or spherical domains. We use a Finite Element (FE) approach to automatically implement arbitrary faulting sources and calculate displacement and stress fields induced by slip on the fault. The package makes use of the capabilities of CalculiX, a non commercial FE software designed to solve field problems (see for details), and is freely distributed by request.

The historical sources of large and moderate earthquakes, earthquake catalogues and monographs exist in many depositories in Syria and European centers. They have been studied, and the detailed review and analysis resulted in a catalogue with 181 historical earthquakes from 1365 B.C. to 1900 A.D. Numerous original documents in Arabic, Latin, Byzantine and Assyrian allowed us to identify seismic events not mentioned in previous works. In particular, detailed descriptions of damage in Arabic sources provided quantitative information necessary to re-evaluate past seismic events. These large earthquakes (I0>VIII) caused considerable damage in cities, towns and villages located along the northern section of the Dead Sea fault system. Fewer large events also occurred along the Palmyra, Ar-Rassafeh and the Euphrates faults in Eastern Syria. Descriptions in original sources document foreshocks, aftershocks, fault ruptures, liquefaction, landslides, tsunamis, fires and other damages. We present here an updated historical catalogue of 181 historical earthquakes distributed in 4 categories regarding the originality and other considerations, we also present a table of the parametric catalogue of 36 historical earthquakes (table I) and a table of the complete list of all historical earthquakes (181 events) with the affected locality names and parameters of information quality and completeness (table II) using methods already applied in other regions (Italy, England, Iran, Russia) with a completeness test using EMS-92. This test suggests that the catalogue is relatively complete for magnitudes >6.5. This catalogue may contribute to a comprehensive and unified parametric earthquake catalogue and to a realistic assessment of seismic hazards in Syria and surrounding regions.

This book contains the proceedings of the 1st WSEAS International Conference on Environmental and Geological Science and Engineering (EG'08) which was held in Malta, September 11-13, 2008. This conference aims to disseminate the latest research and applications in Renewable Energy, Mineral Resources, Natural Hazards and Risks, Environmental Impact Assessment, Urban and Regional Planning Issues, Remote Sensing and GIS, and other relevant topics and applications. The friendliness and openness of the WSEAS conferences, adds to their ability to grow by constantly attracting young researchers. The WSEAS Conferences attract a large number of well-established and leading researchers in various areas of Science and Engineering as you can see from http://www.wseas.org/reports. Your feedback encourages the society to go ahead as you can see in http://www.worldses.org/feedback.htm The contents of this Book are also published in the CD-ROM Proceedings of the Conference. Both will be sent to the WSEAS collaborating indices after the conference: www.worldses.org/indexes In addition, papers of this book are permanently available to all the scientific community via the WSEAS E-Library. Expanded and enhanced versions of papers published in this conference proceedings are also going to be considered for possible publication in one of the WSEAS journals that participate in the major International Scientific Indices (Elsevier, Scopus, EI, ACM, Compendex, INSPEC, CSA .... see: www.worldses.org/indexes) these papers must be of high-quality (break-through work) and a new round of a very strict review will follow. (No additional fee will be required for the publication of the extended version in a journal). WSEAS has also collaboration with several other international publishers and all these excellent papers of this volume could be further improved, could be extended and could be enhanced for possible additional evaluation in one of the editions of these international publishers. Finally, we cordially thank all the people of WSEAS for their efforts to maintain the high scientific level of conferences, proceedings and journals.

This study presents a combined analysis of radon and meteorological time series acquired over several years in a building regularly occupied by workers and occasionally by visitors. The building is founded directly on basaltic tuff in an area characterized by elevated radon levels. A multilevel monitoring system with high spatial and temporal resolution was deployed, consisting of 14 low-cost detectors measuring radon and indoor meteorological parameters; an outdoor weather station was employed for environmental and soil monitoring, and a RAD8 instrument was used to identify the main radon entry points. The monitoring system allowed us to characterize, on daily and seasonal timescales, the variability of radon concentration throughout the building and its dependence on meteorological and anthropogenic factors. Cluster analysis combined with a principal component analysis revealed three distinct meteorological regimes (warm, cold, stormy). Indoor radon concentration centroids in the cold and stormy regimes were associated with up to about 3.9 kBq/m3 at RDP2exp, over an order of magnitude above the EU reference level of 300 Bq/m3, while warm, dry conditions yielded significantly lower levels. Horizontal radon diffusion times ranged from 30 to 90 min, and vertical diffusion times ranged from 90 to 180 min across floors. A 24 h exposure risk assessment shows that occupancy during working hours (08:00–18:00) coincides with the daily radon minimum, but baseline concentrations remain above 300 Bq/m3 even during these periods, necessitating mitigation strategies.

This article deals with the spatial-temporal investigation of the possible relationship of the carbon monoxide (CO) anomalies with the 2013 Mw =6.7 Lushan earthquake. The complexity of the seismogenic environment contributes to the irregular spatial distribution of CO background. Accurate estimation of the spatial reference background is crucial for precisely detecting seismic-related anomalies. In this study, we proposed an improved Robust Satellite Techniques (RST) approach, in which long-term spatial common variation was incorporated into reference background using multichannel singular spectrum analysis (MSSA) together with spatial clustering. Using the MSSA-RST approach, we detected CO anomalies associated with the Lushan earthquake, utilizing MERRA-2 data spanning from 180 days before to 90 days after the mainshock, and compared the results with those obtained using typical RST. The cumulative CO anomalies exhibited two accelerated growths in the form of a sigmoidal trend: from −51 to −40 days, and from −26 days to 15 days after the mainshock. Spatially, CO anomalies were distributed around the epicenter and along fault zones. Subsequently, we analyzed seismic events and deformation to explore the association between CO anomalies and the Lushan earthquake. The lithospheric Benioff strain also displayed two sigmoid accelerations preceding the mainshock, consistent with cumulative CO anomalies. Some high-value regions in the GPS velocity field were aligned with CO anomaly clusters surrounding Longmenshan, Xianshuihe, Zemuhe, and Anninghe faults. Furthermore, the spatial correspondence and temporal sequence of multiple parameters provide additional support for the potential seismic origin of most atmospheric CO anomalies detected by the new approach, which can be explained by lithosphere-atmosphere–ionosphere coupling (LAIC) models.

In this study, we analysed remote sensing data collected during the Beirut port explosion on 4 August 2020 at 15.08 UT. For this purpose, we selected three Low-Earth-Orbit (LEO) satellite missions that passed near the Beirut port explosion site immediately after the event. The satellites involved were Swarm-B, the Defence Meteorological Satellite Program (DMSP-F17), and the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC-2). This study focused on identifying the possible ionospheric signatures of explosion in both hemispheres. The conjugate hemispheric points were traced using the International Geomagnetic Reference Field (IGRF) model. We found that the satellite data revealed disturbances not only over the explosion site in the Northern Hemisphere, but also in its corresponding conjugate region in the Southern Hemisphere. Ionospheric electron density disturbances were observed poleward in the conjugate hemispheres along the paths of the Swarm and DMSP satellites, whereas the magnetic field data from Swarm-B showed both equatorward and poleward disturbances. Additionally, the ionospheric disturbances detected by Swarm-B (18:52 UT) and DMSP-F17 (16:30 UT) at the same location suggested travelling ionospheric disturbance (TID) oscillations with identical spatial patterns for both satellites, whereas the disturbances observed by COSMIC-2 south of the explosion site (10°N) indicated the radial propagation of TIDs. COSMIC-2 not only recorded equatorward topside (>550 km) ionospheric electron density disturbances, but also in the conjugate hemispheres, which aligns with the time frame reported in previous studies. These ionospheric features observed by multiple LEO satellites indicate that the detected signatures originated from the event, highlighting the importance of integrating space missions for monitoring and gaining deeper insight into space hazards. The absence of equatorward ionospheric disturbances at the altitudes of DMSP-F17 and Swarm-B warrant further investigation.

Extracting earthquake precursors from observation data is a long-standing challenge. In principle, the observation data are the first-hand information to understand the earthquake process, and anomaly extraction is a necessary step to discover earthquake precursors, as well as hopefully enable earthquake prediction. At present, advancements in monitoring systems and anomaly extraction technologies have improved our understanding of many earthquake cases. However, due to diverse geophysical measurement techniques, as well as there could be some different theories and consequent signals induced by earthquake activity, anomaly extraction techniques remain fragmented, with no unified technological consensus established. This review uniquely summarizes time-series-based anomaly extraction techniques across geophysical observations for earthquake precursors, unlike existing reviews that mainly concentrate on individual geophysical observation types. Specifically, we outline the classification of anomaly extraction techniques in time-series observations by investigating their data types, the associated anomaly types, and the corresponding extraction methods. It is found that the growing data and precursor knowledge have shifted extraction methods from traditional to data-driven approaches, transforming anomalies into complex contextual or pattern signals preceding earthquakes. This review offers a practical reference framework for assessing extraction techniques and refining their performance in terms of data and anomaly types. We also hope this investigation will advance understanding of evolving extraction methods and their predictive potential.