Journal of Atmospheric and Solar-Terrestrial Physics最新文献

{"title":"Contrasting features of rainfall microphysics as observed over the coastal and orographic region of western ghat in the inter-seasonal time-scale","authors":"Kaustav Chakravarty ,&nbsp;Rohit P. Patil ,&nbsp;Gargi Rakshit ,&nbsp;G. Pandithurai","doi":"10.1016/j.jastp.2024.106221","DOIUrl":"10.1016/j.jastp.2024.106221","url":null,"abstract":"<div><p>The paper aims to highlight the contrasting inter-seasonal variability of raindrop size distribution (DSD) as observed over Mumbai (representing a coastal city) and Mahabaleshwar (representing an orographic station in the Western Ghat mountain range) of Indian peninsula for a continuous period of four years (2018–2022). Upon examining the microphysical features of precipitation patterns, it is observed that raindrops with diameter of 3 mm and above dominate the rainfall in Mahabaleshwar during the pre-monsoon period, while the same with diameter of 1.5 mm and above dominate Mumbai's rainfall during the monsoon months. Additionally, the study finds a strong diurnal variation in rainfall occurrences during the pre-monsoon period for both the stations, while such variation is absent during the monsoon period. The analysis suggests that the Convective Available Potential Energy (CAPE) plays a significant role in these divergent diurnal patterns. Furthermore, the paper explores the relationship between mass-weighted mean diameter (<em>D</em>_<em>m</em>) - rain rate (<em>R</em>) values and shape (<em>μ</em>) versus slope (<em>Λ</em>) parameters as obtained from the two stations during the inter-seasonal phases of the monsoon. The results indicate that, during the pre-monsoon period, higher rain intensities (&gt;16 mm/h) correspond to a dominant <em>D</em>_<em>m</em> value in Mahabaleshwar's rainfall. Conversely, during the monsoon months, higher <em>D</em>_<em>m</em> values are noticeable in Mumbai's rainfall. Thus by connecting with all the analysis done through this paper, it can be said that convective rainfall dominates the pre-monsoon period over orographic station, with convectivity becoming evident at rain rates greater than 16 mm/h. On the other hand, during the monsoon period, local thermodynamic conditions and higher moisture availability trigger the formation of deep convective clouds over coastal areas, thereby resulting for more convective rainfall in the coastal city compared to the orographic station.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140404771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time-dependent magnetic anomaly variations in Turkey and Greece using swarm satellites: A comprehensive precursory multi-track analysis of M≥6 earthquakes from 2017 to 2020","authors":"İlkin Özsöz ,&nbsp;Oya Ankaya Pamukçu ,&nbsp;Erdinç Timoçin","doi":"10.1016/j.jastp.2024.106210","DOIUrl":"https://doi.org/10.1016/j.jastp.2024.106210","url":null,"abstract":"<div><p>This article presents a comprehensive multi-track analysis aimed at investigating time-dependent magnetic anomaly variations in Turkey and Greece resulting from five M ≥ 6 earthquakes occurring between January 2017 and October 2020. The study utilizes data from the Swarm satellites and employs various analytical techniques, including first-time derivative calculations, long-wavelength component removal, and moving RMS filters, to construct cumulative anomaly count graphs for each magnetic component. By eliminating the influence of the external magnetic field, we focus solely on the magnetic components (X, Y, Z, and F). The changes in magnetic anomalies before, during, and immediately after the earthquakes are carefully interpreted. The research systematically analyses the Plomari (June 12, 2017), Kos (July 20, 2017), Doğanyol (January 24, 2020), Özalp (February 23, 2020), and Karlovasion (October 30, 2020) Earthquakes, considering the mainshock and aftershock responses for each magnetic component. The findings reveal intriguing patterns, most notably the emergence of distinctive S-shaped anomalies in various magnetic components. Moreover, the study highlights the influence of significant earthquakes, such as Plomari and Kos, on cumulative anomalous tracks, providing critical insights into magnetic field behavior. Additionally, the study investigates the potential impact of the Özalp Earthquake on the magnetic anomalies observed in the Doğanyol earthquake and explores the relationship between the occurrence of the Doğanyol Earthquake and the precursory anomalies leading to the mainshock of the Özalp Earthquake. Furthermore, the analysis of the Karlovasion earthquake identifies magnetic anomalies preceding the mainshock. Finally, the research subjectively assesses the lateral and vertical scores of the five earthquakes to capability to represent the S-shaped pattern. The Plomari and Kos earthquakes score third and fourth highest, respectively, while the Doğanyol Earthquake achieves the top score and distinctly displays an S-shaped pattern, indicating its significance in the magnetic field behavior. The Özalp Earthquake scores second-best with a distinct S-shaped pattern, while the Karlovasion Earthquake receives the lowest score with no evident S-shaped pattern. Additionally, vertical scores indicate the Y and Z components with more pronounced S-shaped patterns, while the X and F components receive lower scores. Notably, the onshore Doğanyol Earthquake exhibits the most pronounced S-shaped pattern across all magnetic components, attributable to its shallow strike-slip fault at 10 km depth, while the offshore Karlovasion Earthquake, generated by a normal fault at 21 km depth, displays the most scattered pattern, providing valuable information on the influence of tectonic settings on magnetic field behaviour. In conclusion, this study provides valuable insights into the magnetic anomalies associated with seismic events in the region, signific","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140331024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tropical cyclone “Vayu” generated gravity waves (20–60 min) in the mesosphere and lower thermosphere over Kolhapur","authors":"Krishnapriya K ,&nbsp;Sathishkumar S ,&nbsp;Sridharan S ,&nbsp;Jeni Victor N","doi":"10.1016/j.jastp.2024.106211","DOIUrl":"https://doi.org/10.1016/j.jastp.2024.106211","url":null,"abstract":"<div><p>Tropical cyclones are one of the potential sources of gravity waves, which can transport energy and momentum to higher heights through their vertical propagation and interaction with the background flow and thereby influence the dynamics of the upper atmosphere. High-resolution wind data acquired by the Medium Frequency (MF) radar at Kolhapur (16.69°N, 74.24°E) are utilized to study the high frequency gravity waves (20–60 min) associated with the tropical cyclone named “Vayu” formed in the Indian Arabian Sea in June 2019. An enhancement of the gravity wave (GW) activities in the meridional wind is observed during 13–15 June 2019. The source of the gravity wave is the tropical Vayu cyclone of category 2 storm. We employed the gravity wave variance data from NASA's Atmospheric Infrared Sounder (AIRS) satellite for our analysis over stratospheric heights. The enhancement of gravity wave variance in both the stratosphere mesosphere heights and the low values of OLR indicate the strong convection associated with cyclone, the source of observed gravity waves. In the present study we analyzed the horizontal propagation direction of the cyclone generated gravity waves using perturbation ellipse, it is found to be in the north–south plane. The temperature profiles obtained from the SABER instrument on board TIMED satellite indicate the presence of mesospheric inversion layer with an amplitude of nearly 40 K on the day of large gravity wave variance (June 13, 2019). These results indicate the cyclone can generate gravity waves which can propagate to higher heights and modify the MLT thermal structure, providing evidence for the vertical coupling between lower and upper atmosphere.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140309856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Penetrating electric field during the Nov 3–4, 2021 geomagnetic storm","authors":"Qian Wu ,&nbsp;Wenbin Wang ,&nbsp;Dong Lin ,&nbsp;Chaosong Huang ,&nbsp;Yongliang Zhang","doi":"10.1016/j.jastp.2024.106219","DOIUrl":"https://doi.org/10.1016/j.jastp.2024.106219","url":null,"abstract":"<div><p>We simulated the Nov 3–4, 2021 geomagnetic storm event penetrating electric field using the Multiscale Atmosphere-Geospace Environment (MAGE) model and compared with the NASA ICON observation. The ICON observation showed sudden enhancement of the vertical ion drift when the penetrating electric field arrived at the equatorial region. The MAGE model simulated vertical ion drifts have the similarly fast enhancement that shown in the ICON data at the same UT time and satellite location. Hence, ICON ion drift data was able to verify MAGE simulation, which couples the magnetospheric model was able to simulate the penetrating electric field very well.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1364682624000476/pdfft?md5=4b2ce1bbd3963a22ef3e9d7d18da5955&pid=1-s2.0-S1364682624000476-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140191466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An updated catalog of IPS radio sources observed by MEXART at 140 MHz for space weather studies","authors":"G. Baron ,&nbsp;E. Aguilar-Rodriguez ,&nbsp;J.C. Mejia-Ambriz ,&nbsp;O. Chang ,&nbsp;J.A. Gonzalez-Esparza ,&nbsp;P. Villanueva ,&nbsp;E. Andrade","doi":"10.1016/j.jastp.2024.106208","DOIUrl":"https://doi.org/10.1016/j.jastp.2024.106208","url":null,"abstract":"<div><p>The Mexican Array Radio Telescope (MEXART) is an instrument dedicated to performing interplanetary scintillation (IPS) observations at 140 MHz. After the MEXART backend’s digitization, the array’s technical capabilities have improved substantially, and we observe new IPS sources. By analyzing observations recorded from June 2020 to June 2022, we present an updated catalog of radio sources observed with an IPS signature by MEXART. First, we implemented an algorithm to treat the noise presented by some channels in the frequency. Next, we obtained the spectra of the observations to get the frequency of the Fresnel’s knee and determine whether each radio source exhibited IPS. We then estimated the source’s flux at 140 MHz by interpolating flux density data to different frequencies using the NASA/IPAC Extragalactic Database. Finally, we present a list of 38 radio sources showing IPS signatures. The source list presents declination, right ascension, and flux at 140 MHz. This updated catalog will allow studies of solar wind properties in the inner heliosphere using MEXART data.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1364682624000361/pdfft?md5=0f2b72369cad14e2e42683c100965f78&pid=1-s2.0-S1364682624000361-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140180712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sporadic-E studies over Southern Hemisphere geomagnetic mid-latitudes","authors":"A.J. Foppiano ,&nbsp;M.A. Bravo ,&nbsp;L.C.A. Resende ,&nbsp;M.A. Arriagada ,&nbsp;P.A. Flores","doi":"10.1016/j.jastp.2024.106200","DOIUrl":"https://doi.org/10.1016/j.jastp.2024.106200","url":null,"abstract":"<div><p>Sporadic-E (Es) are characterized by denser layers whose formation could be related to wave activity in the lower thermosphere, such as planetary waves, tides, and gravity waves. The first aim of this work was to analyze the Es layer occurrence under different geophysical conditions to establish the importance of these waves. Thus, we used ionosonde observations of four different locations at mid-latitudes that are King George Island (62.2°S, 58.8°W), Argentine Islands (65.3°S; 64.3°W), on the Antarctic Peninsula longitude sector, and Canberra (35.3°S; 149.0°E) and Hobart (42.9°S; 147.3°E), on the Australian sector. The data are divided for winter, equinox, and summer during low (1986–87) and high (1989–90) solar activity levels. Seasonal means of the Es layer frequency and height parameters have been computed. The results show that the diurnal variations of the Es layer occurrence and their frequency parameters are similar for all seasons and solar activity levels over the two longitude sectors. These results do not support the expectations that gravity-wave momentum-fluxes are significant in this case study. The height of the Es layers over Antarctica is about 10 km higher than over Australia. Also, the Es occurrence is higher at night over Antarctica. Computed blanketing Es layer frequency (<em>fb</em>Es) using known formulae are almost identical to those observed for all locations and seasons during low and high solar activity. The Es frequency dependence on solar activity level is also different from what has been shown elsewhere.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140041842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Forecasting geomagnetic activity: Neural networks, moving windows and state transition models","authors":"Gordon Reikard","doi":"10.1016/j.jastp.2024.106201","DOIUrl":"https://doi.org/10.1016/j.jastp.2024.106201","url":null,"abstract":"<div><p>Geomagnetic activity shows high degrees of nonlinear variability. The probability distribution has heavy tails, and there are intermittent outliers. This has led to increased interest in forecasting using neural networks and nonlinear regressions, which include time-varying coefficient techniques. Because geomagnetic storms pose the greatest threat to satellites and power grids, there is a particular interest in predicting outlying events. The model proposed here combines two techniques. Neural networks and regressions are trained over moving windows of observations, so that the weights or coefficients adjust to new data. Second, logistic regression is used to predict the periods of high activity, and the cumulative distribution function is used as a causal input in time series and machine learning models. The data set is the Aa index, corrected for secular drift. Forecasting experiments are run over horizons of 1–4 days. The other models include time-varying parameter regressions and a recurrent neural network with fixed weights. The model combining the neural net and logistic regression achieves the most accurate forecast, although the regression is a close second. The ability to predict outliers depends on the width of the moving window. With wider windows, the overall error is lower, but the forecasted values fall into a narrower range, missing the outliers. With narrower windows, the model predicts the outliers better but is vulnerable to calling them at the wrong times, so the average error is higher. Further, while the model achieves more accurate predictions at 1 day, at longer horizons the accuracy deteriorates quite rapidly.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140030593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermodynamic and stability features of the atmospheric boundary layer over Kochi during different monsoon seasons based on radiosonde profiles","authors":"Linsha C. L ,&nbsp;Reshma T ,&nbsp;Hamza Varikoden ,&nbsp;Vishnu R","doi":"10.1016/j.jastp.2024.106209","DOIUrl":"10.1016/j.jastp.2024.106209","url":null,"abstract":"<div><p>The characteristics of thermodynamic parameters at different pressure levels have been studied using radiosonde data for the period 1989–2019 during different seasons incorporating sea-land breeze circulation influences over Kochi, in western peninsular India. It is also observed that the variation in lower tropospheric stability of (LTS) is found to be influenced by other thermodynamic parameters, such as temperature, mixing ratio, potential temperature, equivalent potential temperature, CAPE, and CINE at various pressure levels. The average value of temperature, potential temperature, mixing ratio, and equivalent potential temperature was maximum during the pre-monsoon season. At 700 hPa level, the average value of the mixing ratio was high during the sea breeze circulation of pre-monsoon season. The average value of equivalent potential temperature at 700 hPa level was maximum for the southwest monsoon season. A decreasing trend was observed in lower tropospheric stability (LTS) over the region in all seasons except for the winter season during the sea breeze circulation. The positive trend of LTS was observed during the sea breeze circulation time during the winter season, and it has a strong correlation with the positive trend in temperature and potential temperature at the 700 hPa level. Moreover, the southwest monsoon season exhibited a substantial decrease in LTS, potentially associated with an increasing trend in temperature, potential temperature, mixing ratio, and equivalent potential temperature at the surface level. CAPE has a significant increasing trend only for the sea breeze circulation period during the monsoon season. Additionally, CINE displayed an increasing trend across all seasons, with higher values observed during the winter and post-monsoon seasons.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140128326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative Study on Lightning Data between the Fengyun-4A Satellite and the National Lightning Monitoring Network in Guizhou, China","authors":"Ankun Wu ,&nbsp;Lujin Cai ,&nbsp;Juncheng Guo ,&nbsp;Min Ding","doi":"10.1016/j.jastp.2024.106194","DOIUrl":"10.1016/j.jastp.2024.106194","url":null,"abstract":"<div><p>Clustered data from the Lightning Mapping Imager (LMI) onboard the Fengyun-4A satellite were compared with lightning strike data from the National Lightning Monitoring Network (NLMN) for the period of 22 June–21 September 2020 over Guizhou Province, China. Spatial and temporal distributions of lightning counts for LMI and NLMN were mostly consistent, although the NMLN detected approximately ten times more lightning per hour than LMI. Influenced by background solar radiation, LMI data exhibited strong diurnal variations in lightning radiance, with significantly higher values during daytime. In contrast, NLMN lightning peak currents showed no similar variations. While no clear relationship was observed between the spatial distributions of LMI lightning density and radiance, a negative correlation was found between NLMN lightning density and peak current. Additionally, the matching rate (MR) for LMI and NLMN data, dependent on spatiotemporal matching criteria, was analyzed. The MR increased sharply with the extension of the temporal interval up to 2 s, then stabilized for longer intervals. In contrast, the MR was strongly influenced by the spatial matching grid cell size. For instance, within a 2-s temporal interval, an MR of 81.1% was estimated for NLMN data within a 27.5-km radius, compared to an MR of 79.8% for LMIG data within a 42.5-km radius. Furthermore, the MR was consistently higher for NLMN compared to LMI. Finally, using Bayes' theorem, we conducted a preliminary assessment of LMI's conditional detection efficiency, employing NLMN lightning data as prior information. The LMI detection efficiency was found to be significantly higher during nighttime than daytime, with values of 50.06% and 100% for daytime and nighttime detections, respectively, within a 2-s temporal interval and a 37.5-km grid cell.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1364682624000221/pdfft?md5=ea283e2ebbe8025505c8917eed6bd56d&pid=1-s2.0-S1364682624000221-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139920112","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the strength of E and F region irregularities for GNSS scintillation in the dayside polar ionosphere","authors":"Mahith Madhanakumar ,&nbsp;Andres Spicher ,&nbsp;Juha Vierinen ,&nbsp;Kjellmar Oksavik","doi":"10.1016/j.jastp.2024.106197","DOIUrl":"https://doi.org/10.1016/j.jastp.2024.106197","url":null,"abstract":"<div><p>We present results of the study conducted to quantify the relative contribution of different ionospheric regions to phase scintillation in Global Navigation Satellite Systems (GNSS) at the dayside high latitude ionosphere. By taking advantage of the scanning capability of the 32-m EISCAT radar in Svalbard (ESR) and its recurrent favourable location below the dayside auroral region, we developed a methodology to identify conjunctions between the radar and GNSS satellite signals in order to compare density irregularities identified by the radar with scintillation observed in GNSS signals. The analysis revealed that the dayside ionosphere contained irregularities predominantly in the F region with scintillation occurring 77% of the times. The likelihood of observing irregularities in the E region were comparatively less with a scintillation occurrence rate of 42%. The study therefore strongly suggests that the dayside F region is more structured than the E region and is the predominant source region for irregularities that cause scintillation at GNSS frequencies. The associated ionospheric conditions revealed enhanced F region electron and ion temperatures to be collocated with scintillation for majority of the times. This supports the fact that cusp/auroral dynamics play a crucial role in creating F region irregularities which can act as sources of scintillation in GNSS signals. The presented results provide a quantitative estimate of the effectiveness of irregularities and the associated ionospheric conditions in different regions of the dayside ionosphere during scintillation, which are relevant for high latitude modelling and instability studies as well as for space weather applications.</p></div>","PeriodicalId":15096,"journal":{"name":"Journal of Atmospheric and Solar-Terrestrial Physics","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"2024-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1364682624000257/pdfft?md5=1a222190d6f86a8923a8d31a57df61c3&pid=1-s2.0-S1364682624000257-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140041876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}