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Galkin, Ivan
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- PublicationOpen AccessEffective Solar Indices for Ionospheric Modeling: A Review and a Proposal for a Real-Time Regional IRI(2018-01)
; ; ; ; ; ; ; The first part of this paper reviews methods using effective solar indices to update a background ionospheric model focusing on those employing the Kriging method to perform the spatial interpolation. Then, it proposes a method to update the International Reference Ionosphere (IRI) model through the assimilation of data collected by a European ionosonde network. The method, called International Reference Ionosphere UPdate (IRI UP), that can potentially operate in real time, is mathematically described and validated for the period 9–25 March 2015 (a time window including the well-known St. Patrick storm occurred on 17 March), using IRI and IRI Real Time Assimilative Model (IRTAM) models as the reference. It relies on foF2 and M(3000)F2 ionospheric characteristics, recorded routinely by a network of 12 European ionosonde stations, which are used to calculate for each station effective values of IRI indices IG12 and R12 (identified as IG12eff and R12eff ); then, starting from this discrete dataset of values, two-dimensional (2D) maps of IG12eff and R12eff are generated through the universal Kriging method. Five variogram models are proposed and tested statistically to select the best performer for each effective index. Then, computed maps of IG12eff and R12eff are used in the IRI model to synthesize updated values of foF2 and hmF2. To evaluate the ability of the proposed method to reproduce rapid local changes that are common under disturbed conditions, quality metrics are calculated for two test stations whose measurements were not assimilated in IRI UP, Fairford (51.7°N, 1.5°W) and San Vito (40.6°N, 17.8°E), for IRI, IRI UP, and IRTAM models. The proposed method turns out to be very effective under highly disturbed conditions, with significant improvements of the foF2 representation and noticeable improvements of the hmF2 one. Important improvements have been verified also for quiet and moderately disturbed conditions. A visual analysis of foF2 and hmF2 maps highlights the ability of the IRI UP method to catch small-scale changes occurring under disturbed conditions which are not seen by IRI.172 142 - PublicationRestrictedThe ESPAS e-infrastructure: Access to data from near-Earth space(2016)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ;ESPAS, the ‘‘near-Earth space data infrastructure for e-science” is a data e-infrastructure facilitating discovery and access to observations, ground-based and space borne, and to model predictions of the near-Earth space environment, a region extending from the Earth’s atmosphere up to the outer radiation belts. ESPAS provides access to metadata and/or data from an extended network of data providers distributed globally. The interoperability of the heterogeneous data collections is achieved with the adoption and adaption of the ESPAS data model which is built entirely on ISO 19100 series geographic information standards. The ESPAS data portal manages a vocabulary of space physics keywords that can be used to narrow down data searches to observations of specific physical content. Such content-targeted search is an ESPAS innovation provided in addition to the commonly practiced data selection by time, location, and instrument. The article presents an overview of the architectural design of the ESPAS system, of its data model and ontology, and of interoperable services that allow the discovery, access and download of registered data. Emphasis is given to the standardization, and expandability concepts which represent also the main elements that support the building of long-term sustainability activities of the ESPAS e-infrastructure.127 5 - PublicationOpen AccessCorrection to: Effective Solar Indices for Ionospheric Modeling: A Review and a Proposal for a Real-Time Regional IRI(2018-01)
; ; ; ; ; ; ; Correction to: Surv Geophys https://doi.org/10.1007/s10712-017-9438-y158 100 - PublicationOpen AccessMulti‐Instrument Observations of Various Ionospheric Disturbances Caused by the 6 February 2023 Turkey Earthquake(2023)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ; ; ; ; ; ;; ;In this work, we investigate various types of ionospheric disturbances observed over Europe following the earthquake that occurred in Turkey on 6 February 2023. By combining observations from Doppler sounding systems, ionosondes, and GNSS receivers, we are able to discern different types of disturbances, propagating with different velocities and through different mechanisms. We can detect co-seismic ionospheric disturbances close to the epicenter, as well as ionospheric signatures of acoustic waves propagating as a consequence of propagating seismic waves. Unlike the vast majority of past ionospheric co-seismic disturbance studies that are primarily based on Total Electron Content variations, reflecting disturbances propagating around the F-region peak, the focus of the present study is the manifestation of disturbances at different ionospheric altitudes by exploiting complementary ionospheric remote sensing techniques. This is particularly highlighted through ionospheric earthquake-related signatures established as specific ionogram deformations known as multiple-cusp signatures which appear as additional cusps at the base of the F-region attributed to electron density irregularities generated by Rayleigh surface waves that generate acoustic waves propagating up to the ionosphere. Therefore this study underlines the advantage that multi-instrument investigations offer in identifying the propagation of earthquake-related ionospheric disturbances at different ionospheric altitudes and distances from the earthquake epicenter.72 6 - PublicationOpen AccessMulti-instrument detection in Europe of ionospheric disturbances caused by the 15 January 2022 eruption of the Hunga volcano(2022-10-21)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;; ; ;; ; ; ; ;; The 15 January 2022 eruption of the Hunga volcano provides a unique opportunity to study the reaction of the ionosphere to large explosive events. In particular, this event allows us to study the global propagation of travelling ionospheric disturbances (TIDs) using various instruments. We focus on detecting the ionospheric disturbances caused by this eruption over Europe, where dense networks of both ionosondes and GNSS receivers are available. This event took place on the day of a geomagnetic storm. We show how data from different instruments and observatories can be combined to distinguish the TIDs produced by the eruption from those caused by concurrent geomagnetic activity. The Lamb wavefront was detected as the strongest disturbance in the ionosphere, travelling between 300 and 340 m/s, consistent with the disturbances in the lower atmosphere. By comparing observations obtained from multiple types of instruments, we also show that TIDs produced by various mechanisms are present simultaneously, with different types of waves affecting different physical quantities. This illustrates the importance of analysing data from multiple independent instruments in order to obtain a full picture of an event like this one, as relying on only a single data source might result in some effects going unobserved.189 48 - PublicationOpen AccessCOST 296 scientific results designed for operational use(2009-08)
; ; ; ; ; ; ; ; ; ; ; ;Stanislawska, I.; Space Research Centre PAS, Warsaw, Poland ;Belehaki, A.; National Observatory of Athens, Athens, Greece ;Jakowski, N.; DLR, Institute of Communications and Navigation, Neustrelitz, Germany ;Zolesi, B.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Gulyaeva, T. L.; IZMIRAN, Troitsk, Moscow Region, Russia ;Cander, L. R.; Rutherford Appleton Laboratory, Chilton, UK ;Reinisch, B. W.; Center for Atmospheric Research, UMass Lowell, USA ;Pezzopane, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia ;Tsagouri, I.; National Observatory of Athens, Athens, Greece ;Tomasik, L.; Space Research Centre PAS, Warsaw, Poland ;Galkin, I.; Center for Atmospheric Research, UMass Lowell, USA; ; ; ; ; ; ; ; ; ; The main objective of the COST 296 Action «Mitigation of Ionospheric Effects on Radio Systems» is the establishment/ improvement of ionospheric services by coordinating the development of specific algorithms, models, and tools capable of operating in a near-real-time mode. Key elements of these activities are contributions related to monitoring, modelling, and imaging of customer-relevant ionospheric quantities. COST stimulates, coordinates, and supports Europe’s goals of development and global cooperation by providing high quality information and knowledge of ionospheric and plasmaspheric conditions enabling high quality and reliable operation of radio systems. It also provides a platform for sharing such tools as algorithms or models, and for the joint development of advanced technologies. It takes advantage of many national and European service initiatives, for example DIAS (http://dias.space.noa.gr), SWACI (http://w3swaci.dlr.de), ESWUA (http://www.eswua.ingv.it/ingv), RWC-Warsaw (http://www.cbk.waw.pl/rwc), the COST Prompt Ionospheric Database http://www.wdc.rl.ac.uk/cgibin/ digisondes/cost_database.pl, http://www.izmiran.ru/services, and others. Existing national capabilities are taken into account to develop synergies and avoid duplication. The enhancement of environment monitoring networks and associated instrumentation yields mutual advantages for European and regional services specialized for local user needs. It structurally increases the integration of limited-area services, and generates a platform employing the same approach to each task differing mostly in input and output data. In doing so it also provides a complementary description of the environmental state within issued information, as well as providing a platform for interaction among local end users, who define what kind of information they need, for system providers, who finalize the tools necessary to obtain required information, and for local service providers, who do the actual processing of data, tailoring it to specific users’ needs. Such an initiative creates a unique opportunity for small national services to consolidate their product design so that is no longer limited to their own activity, but can serve the wider European services. The development and improvement of techniques for mitigating ionospheric effects on radio systems by the COST 296 Action prepared those services that implemented the new design techniques for the newly announced EU and ESA policy-Space Situation Awareness (SSA). COST 296 developments applied to nowcasting and forecasting services are an essential input to the Operational SSA Ionosphere.300 282