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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.

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.

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.

Investigating slope deformation in densely vegetated or remote areas is a major challenge for slope stability assessment. This study introduces and validates an integrated UAV-borne low-frequency Ground Penetrating Radar (UAV-GPR) and LiDAR methodology to characterize an unstable slope in Melizzano, Southern Italy. Radar data were acquired along an east–west transect at ~1 m above ground level, while high-resolution LiDAR were used to generate a detailed Digital Terrain Model for topographic correction and geomorphological analysis. The processed radargram images subsurface features down to ~15 m, revealing a laterally continuous high-amplitude reflector at ~10 m, interpreted as a key main sliding surface. Chaotic reflections above this interface indicate heterogeneous deposits associated with gravitational deformation, while more homogeneous reflections below correspond to stable geological units. The geometry of the reflector suggests a compound landslide mechanism. Borehole data validate the geophysical interpretation, showing depth discrepancies lower than 2 m. The integration of UAV-GPR and LiDAR enables a reliable correlation between surface morphology and subsurface structures. This non-invasive, spatially continuous approach provides an effective framework for subsurface characterization and for improving the interpretation of landslide geometry and internal structure in challenging environments. This study demonstrates the capability of low-frequency UAV-borne GPR to detect deep-seated sliding surfaces (>10 m) in vegetated environments when integrated with high-resolution LiDAR topography.

An intense surge in the equatorial electron temperature (T e) at sunrise, known as the morning T e overshoot, has been one of the defining ionospheric features since its discovery early in the Space Age. Despite decades of study, the behavior of the morning overshoot during geomagnetic storms remains poorly understood. We report a two-stage response of the morning T e overshoot to geomagnetic activity, uncovered by a neural network model. Electron temperatures show an initial enhancement during the storm's main phase, followed by a drastic depletion exceeding 1000 K and disappearance of the overshoot in the recovery phase. This two-phase change aligns with the early influence of westward prompt penetration electric field, overtaken by the development of the eastward disturbance dynamo later in the storm. These electric field changes affect vertical plasma drifts that redistribute electron densities, modifying ionospheric cooling rates. Our findings provide new insights into the dynamics of one of the most widely studied ionospheric features and showcase the potential of new-generation digital twin models of near-Earth space environment to reveal previously unrecognized physical patterns. Keywords Ionosphere, Electron temperature, Neural networks Electron temperature (Te) is a fundamental parameter characterizing the Earth's ionosphere and its coupling with the neutral atmosphere, magnetosphere and solar wind 1-3. One of the most notable features of the global Te distribution, discovered early in the Space Age, is the morning electron temperature overshoot 4,5 , which represents a rapid Te increase around the geomagnetic equator at sunrise, often in excess of 3000 K 6. It occurs due to energy exchange between newly ionized photoelectrons and ambient thermal electrons. In regions of low plasma density, each ambient electron receives a greater share of energy compared to regions of dense plasma, making this process particularly efficient. At the equator, a unique combination of low electron density due to the downward E × B drift overnight and inefficient heat removal by conduction allows the morning Te overshoot to develop around 05 h of local time (LT) 6,7. The morning overshoot typically persists until electron density increases around ∼09 LT and presents a global Te maximum during geomagnetically quiet times. Climatological aspects of the morning Te overshoot, including its dependence on altitude, seasons and solar activity, have been analyzed extensively and are generally well understood 5,6,8-11. However, few studies have investigated the dynamics of the morning overshoot during geomagnetic storms. An early theoretical study by Wang et al. 12 proposed a negative correlation of electron temperatures in the overshoot region with the geomagnetic Kp index. Using numerical modeling, they reported the strongest Te depletions at mid-latitudes and a drop of Te by a few hundred degrees around the equator. A more recent observational study by Yang et al. 13 reported multi-day oscillations in the morning overshoot and also suggested a negative correlation with the Kp index, although their study used daily-averaged electron temperature values and did not investigate shorterscale variations within geomagnetic storms.

Cold plasma distribution in the ionosphere-plasmasphere system governs wave-particle interactions, plasma energization and loss, and radio wave propagation. A longstanding observational gap at altitudes ∼800-8,000 km has largely prevented studying the coupled dynamics of the two regions. Here, we show that observations by JAXA's Arase mission can bridge this gap. Electron densities inferred from the upper hybrid resonance frequencies measured by Arase are highly consistent with radio occultation profiles from the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) mission, with a median difference of ∼5%. Using the combined COSMIC-Arase data set, we provide a convenient way to reconcile the two regions in empirical models based on the analytical Chapman function inversion for scale height. Our results enable studying fundamental questions about the ionosphere-plasmasphere coupling, their transition, and life cycle of cold plasma in near-Earth space. Plain Language Summary Cold plasma in the ionosphere and plasmasphere plays a critical role in the dynamics of near-Earth space environment. The physical processes within these two regions are different but tightly coupled. Ionospheric particles fill the plasmasphere on the dayside, while the plasmaspheric particles descend into the ionosphere at night and help sustain it in the absence of photoionization. However, how exactly these populations evolve and transfer into one another remains poorly understood due to two longstanding challenges. First, the measurements in the two regions are separated by a gap at altitudes ∼800-8,000 km. Second, fundamentally different techniques are used to measure plasma densities in the plasmasphere and topside ionosphere. Here, we address both of these issues and show that two of the most prominent N e measurement approaches in the respective regions-using wave spectra and radio occultations-yield nearidentical results. Using observations by the Arase mission at altitudes 440-32,000 km, we demonstrate that it is possible to bridge the gap between the ionosphere and plasmasphere. This result enables studying the dynamics of their transition region and several other fundamental questions about the distribution and life cycle of cold plasma in geospace.

The upper transition height (UTH), defined as the altitude where the dominant ion changes from O + to light-ions, is a key parameter in the topside ionosphere. In this study, we propose an innovative approach to retrieve ionospheric UTH over low latitudes by integrating the ion composition measurements from the C/NOFS satellite with the deep learning ionosphere model (DLIM). Compared to the direct UTH observations when the O + composition is 0.5, this approach can retrieve UTH when the O + composition ranges from 0.3 to 0.7. Our approach increases the number of available UTH measurements from approximately 92,100 to 1,075,000, which allows more comprehensive local time (LT) and magnetic latitude coverage. The proposed approach was validated using observations from the incoherent scatter radar (ISR) located in Jicamarca. The UTH between retrieved and measured from ISR shows good agreement, with the average value and standard deviation of discrepancy being 0.32 and 5.81 km, respectively. The retrieved UTH exhibits typical local time, seasonal and magnetic latitudinal dependence. Comparison results show that during low solar flux conditions, the retrieved UTH showed excellent consistency with the measured UTH with a relative error of less than 3%. Further analysis revealed a positive correlation between the UTH and the F10.7 index, which is stronger than results from directly measured UTH and ISR observations. The rate of change of retrieved UTH with respect to the F10.7 index varies with local time and can reach up 9.15 km/sfu at noontime (12:00 LT), which could be linked to the enhancement of E × B drifts. Plain Language Summary This study focuses on the upper transition height (UTH)-the altitude where light-ions begin to dominate over O + in the upper ionosphere. It is a key parameter in ionospheric physics and an important measurement for studying the ionosphere and how it connects to the plasmasphere. The C/NOFS satellite, with its unique elliptical orbit, has become an important means for observing UTH. However, due to the continuous orbital decay of the satellite, it was unable to effectively measure UTH during periods of high solar activity, and thus the satellite could only provide UTH observations from 2008 to 2010. To better study the climatological characteristics of UTH and its influencing factors, this paper proposes a method that combines an empirical model with satellite observation to retrieve UTH using ion observation data from the C/NOFS satellite. This algorithm increases the number of UTH observations from the approximately 92,100 to more than 1,075,000-an expansion by tenfold. Based on this extended data set, not only can the distribution characteristics of UTH with respect to latitude, local time, and season be obtained, but it is also possible to analyze its global variations with solar activity-an aspect that previous studies relying solely on direct observations were unable to achieve.