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Thermodynamic and stability features of the atmospheric boundary layer over Kochi during different monsoon seasons based on radiosonde profiles J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-12 Linsha C. L, Reshma T, Hamza Varikoden, Vishnu R
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
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Study of the ionospheric precursors associated with M w ≥6.0EQ from Ionosonde Stations and GIM TEC J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-08 Junaid Ahmed, Munawar Shah, Talat Iqbal, Muhammad Ali Shah, Ayaz Amin
To study the coupling mechanism between lithosphere, atmosphere and ionosphere, the ionosonde based earthquake (EQ) anomalies provide clear indications for the future events. The Lithospheric-Atmosphere-Ionospheric coupling (LAIC) provides information about pre and post seismic precursors over the seismogenic zone. This study presents the variations in ionospheric critical frequency (F2) of the F2
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CHIRPS rainfall product application for analyzing rainfall concentration and seasonality in Johor river basin, Malaysia J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-07 Zulfaqar Sa’adi, Nor Eliza Alias, Zulkifli Yusop, Muhammad Wafiy Adli Ramli, Mohd Khairul Idlan Muhammad
It is crucial to carry out a spatiotemporal evaluation of rainfall concentration in the Johor river basin (JRB) given that erratic rainfall can lead to floods. The study utilized the CHIRPS rainfall dataset from 1983 to 2018 to determine rainfall concentration using the Concentration Index (CI). To further define the rainfall regime, the Seasonality Index (SI) and Precipitation Concentration Index
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Effects of the Northern Hemisphere sudden stratospheric warmings on the Sporadic-E layers in the Brazilian sector J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-04 Pedro A. Fontes, Marcio T.A.H. Muella, Laysa C.A. Resende, Rodolfo de Jesus, Paulo R. Fagundes, Paulo P. Batista, Valdir G. Pillat, Alexandre Tardelli, Vania F. Andrioli
Tidal and Planetary Wave (PWs) amplitudes are strongly influenced by Sudden Stratospheric Warming (SSW) events. A nonlinear interaction between the tidal winds and planetary waves during the SSW may contribute to the intensification of sporadic-E () layers in the lower thermosphere. This work investigated the relationship between SSW events in the Northern Hemisphere and the layer occurrence at low
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Sporadic-E studies over Southern Hemisphere geomagnetic mid-latitudes J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-04 A.J. Foppiano, M.A. Bravo, L.C.A. Resende, M.A. Arriagada, P.A. Flores
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
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First results of the potential gradient variation in a tropical station in South America (Ica, Peru) J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-02 Rubén Romero, José Tacza, Joseph Arroyo, Francis Prieto, Liliana Macotela, Yovanny Buleje, René Loayza, Ulices Fernandez, Jean-Pierre Raulin
Measurements of the potential gradient (PG) under fair weather conditions at new locations are crucial for monitoring the global electric circuit. In this study, we analyzed the variations in PG recorded in Ica city, Peru, during the period from March 2018 to December 2022. Our analysis involved a detailed comparison of PG with various meteorological parameters such as rainfall, wind speed and direction
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On the strength of E and F region irregularities for GNSS scintillation in the dayside polar ionosphere J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-02 Mahith Madhanakumar, Andres Spicher, Juha Vierinen, Kjellmar Oksavik
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
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Improvement of topside ionosphere and plasmasphere estimation in ionospheric simulation system J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-02 Telmo dos Santos Klipp, Adriano Petry, Haroldo Fraga de Campos Velho
This work is based on the results for a complete solar cycle of 11 years (2011–2021) from the ionospheric simulation system used in the Brazilian Space Weather program. The electron density profiles generated were integrated in height and compared to the International GNSS Service (IGS) vertical total electron content (vTEC) data. Experiments have shown an inadequate electron concentration decay with
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Evaluation of dB/dt amplitudes and sources over the Brazilian region during geomagnetic storms in the 2021–2022 biennium J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-02 G.B.D. Silva, L.R. Alves, K.V. Espinosa, V.M. Souza, L.A. da Silva, J.E.R. Costa, M.B. Pádua, S.A. Sanchez
The rate of change of the geomagnetic field () observed at Earth’s surface has been used as a proxy of geomagnetically induced currents, which are known to be hazardous for grounded technological systems such as high-voltage power grid systems. The rates have been well characterized in the high latitude region (), but much less information is available for the low latitudes to date. To overcome this
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Forecasting geomagnetic activity: Neural networks, moving windows and state transition models J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-03-01 Gordon Reikard
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
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Terminator effect in the model Schumann resonance signals J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-02-28 A.P. Nickolaenko, Yu P. Galuk, M. Hayakawa
We model Schumann resonance (SR) amplitude variations driven by the diurnal and seasonal motion of the day–night interface in the Earth – ionosphere cavity that is regarded as the terminator effect. The current moment of the equatorial source is a constant. The observer occupies the middle, the high latitudes, or the South Pole. Vertical electric field is calculated at the frequencies 8, 14, and 20
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Lightning detection comparison between the Fengyun-4A lightning mapping imager and the national lightning monitoring network in Guizhou, China J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-02-17 Ankun Wu, Lujin Cai, Juncheng Guo, Min Ding
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
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Can cloud images help in predicting geomagnetic storms? J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-02-15 Rissnalin Syiemlieh, Eeshankur Saikia
Solar activity and Cosmic Ray particles are known to have an effect on the formation of structural clouds through changes in temperature. With an increase in solar activity, coronal mass ejection increases, leading to an increase in temperature in the Earth’s atmosphere. The change in temperature is related to the change in cloud formation and rainfall distribution, and hence the change in climate
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Reassessing the cooling that followed the 1991 volcanic eruption of Mt. Pinatubo J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-02-15 Alberto Boretti
A cooling of up to 0.5 °C which lasted 18–36 months is attributed to the 1991 Mt. Pinatubo eruption. A simple mathematical approach is here applied to the 43-year-long satellite global temperature time series. This time series is fitted with a parabolic function representing global warming, multiple sinusoidal functions representing natural variability, and a rectangular function representing the cooling
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Investigation on the spatiotemporal and vertical structure of ice cloud and aerosol parameters from multi-source satellite datasets (2007–2021) over the Tarim Basin, China J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-02-10 Honglin Pan, Gang Ren, Minzhong Wang, Jin Wang, Kanike Raghavendra Kumar
Aerosol effects upon ice clouds remain the most considerable uncertainty of the global climate forcing uncertainties. Dust aerosol and ice cloud properties over Tarim Basin (TB), China, from 2007 to 2021 are analyzed based on the simultaneously retrieved multiple satellite observations. The present study examines the variations and potential interaction mechanisms among different ice clouds and aerosol
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How to identify and forecast severe space weather events J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-02-02 N. Balan, Qing-He Zhang, S. Tulasi Ram, K. Shiokawa, Zan-Yang Xing
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Combining effects of cloud microphysical and planetary boundary layer parameterization schemes on the prediction of tropical cyclone intensity J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-02-02 Chen Chen, Jiangnan Li
The numerical simulation of tropical cyclone (TC) can be affected by the choices in physics parameterization schemes. These effects can be from the single scheme or the combination of multiple ones due to closely linked physical processes. Previous studies have discussed the roles of different schemes in TC simulation, but the roles of scheme combinations still remain to be explored. To investigate
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Enhancing precipitation estimation accuracy: An evaluation of traditional and machine learning approaches in rainfall predictions J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-01-17 Ye Yin, Jun He, Jie Guo, Wenwen Song, Hao Zheng, Jia Dan
The mounting frequency of extreme precipitation events globally, affecting human activities, has spotlighted the need for precipitation research. Although beneficial for precipitation assessment, rain gauges are spatially constrained, hindering data collection over large regions. In contrast, weather radar provides a broad detection scope and high-resolution capabilities, positioning it as an attractive
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Impact of sudden stratospheric warming on middle atmospheric circulation in the southern hemisphere: A comparative study J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-01-12 G. Mitra, A. Guharay
A comparative study on the impact of rare Southern Hemisphere (SH) Sudden Stratospheric Warmings (SSW) on the middle atmospheric circulation is investigated using a global reanalysis dataset. Since the SH SSW generally occur around spring equinox marking the seasonal transition, so an attempt has been made to isolate the seasonal transition effect from the actual data by carrying out deseasoning to
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A method for calculating real-time ZTD grid data in Chinese regions based on GNSS ZTD modified ERA5 grid products J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2024-01-12 Zhimin Sha, Fangxin Hu, Pengzhi Wei, Shirong Ye, Yixin Zhu
The low spatial and temporal resolution and poor accuracy of real-time zenith tropospheric delay (ZTD) have always been one of the main constraints during the development of real-time GNSS applications. This paper presents a method to obtain real-time ZTD grid data in Chinese regions utilizing the ZTD-modified ERA5 grid products from GNSS stations. Initially, the original ZTD fitting function for vertical
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The multiview observatory for solar terrestrial science (MOST) J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-12-18 N. Gopalswamy, S. Christe, S.F. Fung, Q. Gong, J.R. Gruesbeck, L.K. Jian, S.G. Kanekal, C. Kay, T.A. Kucera, J.E. Leake, L. Li, P. Mӓkelӓ, P. Nikulla, N.L. Reginald, A. Shih, S.K. Tadikonda, N. Viall, L.B. Wilson, S. Yashiro, L. Golub, B.V. Jackson
We report on a study of the Multiview Observatory for Solar Terrestrial Science (MOST) mission that will provide comprehensive imagery and time series data needed to understand the magnetic connection between the solar interior and the solar atmosphere/inner heliosphere. MOST will build upon the successes of SOHO and STEREO missions with new views of the Sun and enhanced instrument capabilities. This
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Developing Iran's empirical zenith wet delay model (IR-ZWD) J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-12-10 Masoud Dehvari, Saeed Farzaneh, Ehsan Forootan
The presence of water vapor in the lower atmosphere can introduce errors in satellite-based geodetic observations. Accurate modeling of this part of atmospheric delay is particularly challenging due to the considerable variations of water vapor. Therefore, constructing a reasonable model to predict Zenith Wet Delay (ZWD) can improve the accuracy of geodetic observations and positioning techniques.
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A curious case of monsoon low frequency reverberations from the mighty Himalayas J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-12-08 Mohammad Salam, Imran Khan, Samia Faiz Gurmani, Amir Sultan, Talat Iqbal
This paper presents an investigation of monsoon-generated infrasound events recorded in Islamabad, Pakistan. The majority of these events originate from a specific azimuth band, pointing towards the Himalaya mountain range in the Indian subcontinent. Although the monsoon phenomenon is well-known to develop over the Bay of Bengal and the Arabian sea and enters Pakistan along the foothills of Himalayas
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Multifractal analysis of the Southern Oscillation Index J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-11-25 Sebastian Jaroszewicz, Maria C. Mariani, Osei K. Tweneboah, Maria P. Beccar-Varela
In this paper, multifractal properties of the Southern Oscillation Index (SOI) have been analyzed using Empirical Mode Decomposition (EMD) and Multifractal Detrended Fluctuation Analysis (MFDFA) for the time interval between 1991 to 2020. The joint application of the EMD and detrended fluctuation analysis methods allowed the signal to be separated into three subsets, each with different scaling properties
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Long-term equatorial ionosphere variations over Ethiopia J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-11-21 Sadya Mohammed, Tsegaye Kassa, Fasil Tesema
This paper focuses on the investigation of the long-term behavior of the equatorial ionosphere in Ethiopia. To explore the extended ionospheric variations, we analyze Total Electron Content (TEC) fluctuations in conjunction with solar activity indices, including F10.7 radio flux, EUV radiation, and Sunspot Number (SSN). The dataset used encompasses GPS-derived TEC records spanning 11 consecutive years
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A novel rainfall forecast model using GNSS observations and CAPE in Singapore J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-11-16 Zhuoya Liu, Yi Wen, Xun Zhang, Mian Wang, Shuzhou Xiao, Yuan Chen, Lin He
Precipitable water vapor (PWV) and zenith total delay (ZTD) are highly correlated indicators used for forecasting rainfall effectively. These two factors are widely used when establishing qualitative and quantitative rainfall forecast models. Another indicator, however, convective available potential energy (CAPE), is also highly correlated with the occurrence of rainfall, but has not been combined
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Global ozone variability J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-11-17 Motirh Al-Mutairi, Modhi O. Alotaibi, Heshmat AbdelBasset, Abdallah Abdeldym, Ayman Badawy
In this work total column ozone (TCO) analysis and variability over globe has been studied during the period 1959–2022 using monthly mean data from ERA5 reanalysis database. The lower values of TCO occurs in equatorial latitudes, while the higher values of TCO appears over the mid-latitude and subpolar latitudes in both hemispheres (slightly farther poleward in the NH). The higher values of the coefficient
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Free-tropospheric aerosols contribute to large aerosol optical depth at a remote, inland location with insignificant anthropogenic emissions J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-11-11 A. Ajay, N. Anand, Y.A. Adithya Kaushik, G. Ilavazhagan, K. Sunilkumar
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Physical effects from the powerful Tonga volcanic eruption of January 15, 2022, in the earth–atmosphere–ionosphere–magnetosphere system J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-11-08 L.F. Chernogor
The powerful Tonga volcanic explosion and eruption has been reliably determined to cause numerous processes on a global scale; nevertheless, a comprehensive model of these processes is absent in the literature, which remains an urgent scientific objective. The purpose of this paper is to thoroughly analyze and model the main physical processes that accompanied the volcanic explosion within the Earth
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Atmospheric electric field effects on cosmic rays detected by the Solar Neutron Telescope at Sierra Negra J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-11-04 J. Newton-Bosch, L.X. González, J.F. Valdés-Galicia, O.G. Morales-Olivares, Y. Muraki, S. Shibata, Y. Matsubara, T. Sako, K. Watanabe, M.A. Sergeeva, F. Monterde-Andrade, S. Perea-Contreras, E. Ortiz, O. Musalem, A. Hurtado, R. Taylor
The influence of thunderstorms’ atmospheric electric fields (AEF) on secondary cosmic rays (CR) detected at high altitude was studied. Using data obtained during the period October 2019 to March 2020 by the Solar Neutron Telescope (SNT) and a Boltek EFM-100 AEF monitor installed in the Sierra Negra Cosmic Ray Observatory (SN-CRO) located at 4580 m a.s.l. in Mexico. With measurements from the EFM-100
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Structure and variations of global planetary boundary layer top from 2008-2022 multiple GNSS RO observations J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-28 Huihuang Xing, Shuanggen Jin
The structural changes at the planetary boundary layer (PBL) top are very complex and closely related to climate and environmental changes. With the development of Global Navigation Satellite System Radio Occultation (GNSS RO), it provides a good opportunity to estimate and study PBL variations. In this paper, long-term variations and structures of planetary boundary layer height (PBLH) from 2008 to
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Relating photometric and magnetic properties of structures at solar surface J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-18 Vladimir Obridko, Dmitry Sokoloff, Maria Katsova
We investigate sharp structures visible in solar magnetic field tracers. It is shown that the sunspot magnetic boundaries do not coincide with the photometric ones. Moreover, there is no clear boundary of the magnetic field in the vicinity of sunspots. Thus, the widely accepted concept of magnetic tubes with sharp edges is not always correct and should be used with caution. It is also shown that even
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Magnetic flux rope structures associated with filament channels: Two case studies J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-20 H. Xie, N. Gopalswamy, S. Akiyama, S. Yashiro, P. Makela
We report on two case studies regarding the magnetic flux rope (MFR) structure of coronal mass ejections (CMEs) near the Sun and at 1 au. The event is a stealth streamer blow-out CME on 2011 March 25 from AR11176 showing a typical three-part bubble-like flux rope structure. No apparent eruptive signatures (e.g., two-ribbon flare, and post-eruption arcade (PEA)) were detected in the solar disk images;
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Causes of hemispheric differences in polar cap indices J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-18 M. Lockwood
Two recent papers by Troshichev et al. (2023) and by Lockwood (2023) have presented different physical mechanisms that cause simultaneous polar cap indices, measured close to the geomagnetic poles in the north and south hemispheres, to differ even though their overall behaviour is very similar. Several effects are described but the two main mechanisms discussed are the effect of the dawn–dusk (Y) component
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Ionospheric response over the middle ASIAN region to the may 1967 geomagnetic storm J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-14 Galina Gordiyenko
Ionospheric effects over the five Middle Asian ionospheric stations to the major space weather event of the May 25–26, 1967 geomagnetic storm with the Dst-index of −387 nT are studied based on ionosonde measurements that were not previously considered: Alma-Ata (43.25N, 76.92E), Karaganda (49.82N, 73.08E), Novokazalinsk (45.76N, 62.12E), Tashkent (41.33N, 69.62E), Ashkhabad (37.90N, 58.30E). The study
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Low latitude Pi2 pulsations at Desalpar, Gujarat, India: A statistical analysis of the influences of magnetic storms/substorms, seasons, and solar cycles J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-11 Prasanna Simha C, Madhusudhana Rao Katlamudi, Jayashree Bulusu
In this paper, we investigate the characteristics of geomagnetic pulsations (Pi2) using ground magnetometer data from the Induction Coil Magnetometer of Desalpar, Kachchh, Gujarat, India. We report here the morphology of Pi2 bursts (6–25 mHz) and their local temporal variations over the period of 2013–2017. The investigation is being conducted to study the effects of Sun-Earth interaction on the occurrences
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Long-term changes in solar activity and irradiance J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-13 Theodosios Chatzistergos, Natalie A. Krivova, Kok Leng Yeo
The Sun is the main energy source to Earth, and understanding its variability is of direct relevance to climate studies. Measurements of total solar irradiance (TSI) exist since 1978, but this is too short compared to climate-relevant time scales. Coming from a number of different instruments, these measurements require a cross-calibration, which is not straightforward, and thus several composite records
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Diurnal variations in lightning over India and three lightning hotspots: A climatological study J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-10 Unashish Mondal, Sreelekshmi S, S.K. Panda, Anish Kumar, Someshwar Das, Devesh Sharma
Advancements have been made in the field of lightning research. A study on lightning frequency in India, a tropical hotspot, has not been conducted despite the existence of a global climatology on mean flash rate lightning. Lightning climatology in India is determined using high-resolution datasets from MicroLab-1 and Tropical Rainfall Measuring Mission (TRMM) satellites and Lightning Imaging Sensor
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Semidiurnal nonmigrating tides in low-latitude lower thermospheric NO: A climatology based on 20 years of Odin/SMR measurements J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-07 Francesco Grieco, Yvan Orsolini, Kristell Pérot
The Sub-Millimetre Radiometer (SMR) on board the Odin satellite provides almost 20 years of nitric oxide (NO) measurements in the mesosphere and lower thermosphere (MLT) at equatorial crossing local solar times (LSTs) of 6 AM and 6 PM. In this study, we use Odin/SMR observations to estimate how lower thermospheric NO mixing ratios at low latitudes are affected by solar nonmigrating tides. Most of the
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The role of extreme geomagnetic storms in the Forbush decrease profile observed by neutron monitors J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-06 Kalpesh Ghag, Prathmesh Tari, Anil Raghav, Zubair Shaikh, Omkar Dhamane, Utsav Panchal, Greg Hilbert, Mayuri Katvankar, Komal Choraghe, Digvijay Mishra, Kishor Kumbhar
The Forbush decrease (FD) and Geomagnetic storm (GS) are the two distinct space weather events having common causing agents like interplanetary coronal mass ejection (ICME) or corotating interacting region (CIR). Generally, large-amplitude FDs and extreme GSs are caused by ICME. Here, we studied eight ICME induced extreme storms and their effects on respective FD profiles as observed by neutron monitors
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Duration and extent of solar X-ray flares and shortwave fadeouts likely to impact high frequency radio wave propagation based on an evaluation of absorption at 30 MHz J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-10-06 R.A.D. Fiori, N.C. Rogers, L. Nikitina, V. Lobzin, E. Rock
High frequency (HF; 3–30 MHz) radio wave propagation can be impacted by absorption that results from enhanced photoionization in the dayside D-region following a solar X-ray flare. A database of >25,000 solar X-ray flares was evaluated to characterize the relationship between flare duration and the peak of the 0.1–0.8 nm solar X-ray flux. Expressions describing the mean and 90th percentile duration
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Impact of solar variability on Indian summer monsoon through large scale circulations J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-09-21 Vasundhara Barde, Aditi Upadhyay, Jayashree Bulusu, A.P. Dimri
Via large-scale circulations, the role of solar variability on the Indian summer monsoon is investigated. Standardized anomaly is used to identify years of solar maxima and minima. Statistical analysis such as moving mean, empirical mode decomposition, and wavelet analysis are used to determine the plausible relationship between solar variability, large scale circulations such as El- Niño 3.4 SST anomaly
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Equinoctial asymmetry of plasma bubble occurrence and electric field at evening: GPS and ionosonde measurements in Southeast Asia J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-09-16 Yuichi Otsuka, Prayitno Abadi, Kornyanat Hozumi, Alif Almahi
We have investigated equinoctial asymmetry of scintillation occurrence and zonal irregularity drift velocity observed with closely-spaced GPS receivers at Kototabang (0.20°S, 100.32°E; geomagnetic latitude 10.6°S), Indonesia during a period from 2003 to 2016, and found that the scintillation occurrence rate is higher in Mar. equinox than in Sep. equinox, and that the eastward drift velocity at post-sunset
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Comprehensive analysis of droughts over the Middle East using IMERG data over the past two decades (2001–2020) J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-09-15 Elham Ghasemifar, Zahra Sonboli, Mahin Hedayatizade
The Middle East is home to approximately 475 million people, most of whom face food insecurity due to severe and extreme droughts that have affected most regions over the past two decades. In this study, we analyzed the spatio-temporal characteristics of different drought intensities during the period 2001–2020 using the Integrated Multi-satellitE Retrievals for GPM (IMERG) precipitation and ERA5 temperature
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Turbulent kinetic energy dissipation rate in the lower troposphere using the 205 MHz radar at Kochi, India J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-09-09 K.K. Ahana, K. Satheesan, S. Athulya, Ajil Kottayil
The Stratosphere–Troposphere (S–T) radar at Kochi (10.04° N, 76.33° E), India is the first radar operating at 205 MHz. At this location, the atmospheric background parameters such as atmospheric wind, temperature, and humidity show distinct changes from monsoon to winter season in the lower atmosphere. The general wind patterns differ significantly during different seasons, giving rise to differences
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Dayglow O2 Atm emission observations at equatorial and low latitudes by WINDII J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-08-22 Marianna Shepherd, Gordon Shepherd
Observations of the dayglow O2 Atm (0,0) band emission by the WINDII experiment on the UARS for 1992 and 1993 have been employed to study the emission's temporal and spatial variability at equatorial and low latitudes encompassing the latitude range of 30°N to 30°S. The WINDII O2 Atm (0,0) dayglow volume emission rates (VER) allowed day-to-day examination of their morphology over the altitude range
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Analysis of lightning flash rate with the occurrence of flash floods and hailstorms in Peninsular Malaysia J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-08-16 Noraishah Bahari, Sulaiman Ali Mohammad, Mona Riza Mohd Esa, Mohd Riduan Ahmad, Noor Azlinda Ahmad, Zulkurnain Abdul Malek
This paper will present five flash flood cases in Johor and two hailstorms from Kuala Lumpur and Melaka reported during lightning activities to determine the relationship between lightning flash rate and rainfall that occurred from 2013 to 2017. The flash floods were observed based on lightning data obtained from Tenaga Nasional Berhad Research Sdn. Bhd. (TNBR) and rainfall data from the Department
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Estimates of energy fluxes associated with sprites in the mesosphere J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-08-12 D. Mashao, M. Kosch, M. Füllekrug
We present calibrated estimates of photon flux, lightning peak Poynting flux and Joule heating associated with the brightest region of sprites observed in the mesosphere over South Africa. The sprites' photon fluxes were estimated using 28 sprites events (observed during the 2019 sprites campaign) calibrated by stars in the sprite's image background. The lightning driven background electric field associated
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On the quiet-time occurrence rates, severity and origin of L-band ionospheric scintillations observed from low-to-mid latitude sites located in Puerto Rico J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-08-11 J. Gomez Socola, J. Sousasantos, F.S. Rodrigues, C.G.M. Brum, P. Terra, A.O. Moraes, R. Eastes
In December 2021 three Global Navigation Satellite System (GNSS) ionospheric scintillation and Total Electron Content (TEC) monitors were installed in Puerto Rico (∼24.5° N dip latitude). The installation is part of an effort to better understand the occurrence of ionospheric irregularities and scintillation at mid-latitudes. Puerto Rico (PR) is commonly referred to as being located at mid-latitudes
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Low latitude atmospheric-ionospheric dynamical response to Prior, During, and Post stages of Super Cyclonic Storm “AMPHAN” J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-07-22 M Gajalakshmi, G J Bhagavathiammal, Kornyanat Hozumi
We present the most intensified Super Cyclonic Storm (SuCS) “AMPHAN” impacts on the low latitude atmospheric–ionospheric system from Ionosonde Observations over Chiang Mai (CMU) located at 18.76°N and 98.93°E. Extensive analysis has been carried out using ionospheric parameters foF2 and hmF2, wind components, and Outgoing Longwave Radiation (OLR). The dynamical response of atmosphere-ionosphere to
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Climatology and interannual variability of the migrating quarterdiurnal tide (QW4) seen in the SABER/TIMED temperatures (2002–2022) J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-07-10 Dora Pancheva, Plamen Mukhtarov
This paper presents a climatological global view on the spatial structure and interannual variability of the high-frequency migrating quarterdiurnal tide (QW4) built on a large statistics of the 21 years (2002–2022) SABER/TIMED temperature measurements. The obtained consistent picture for the vertical structure and phase coherence provide strong support that the observed oscillation is a tide which
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Does the moon meddle with the lower ionosphere? J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-07-10 M. Friedrich
At night free electrons of the lowest ionosphere are either lost by recombination with positive ions, or by attachment to neutrals thus forming negative ions. Whereas for ionisation photons of at least UV energy and/or energetic particles are required, visible light suffices to detach electrons from neutrals. One could compare mesurements of nights with and without moonlight, but one could never rule
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Delayed response of low latitudes TEC during thirty-six geomagnetic storms from 2014 to 2017 J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-07-07 Heba Salah Mohamed, Christine Amory-Mazaudier, Sampad Kumar Panda, O.M. Shalabiea, A. Mahrous
Ionospheric response to the onset of geomagnetic storms is an important aspect for developing models towards better understanding and prediction of ionospheric parameters, particularly over the equatorial and low latitude sectors that are associated with several complexities. Our paper discusses the time response of the ionosphere (Δtiono), where Δtiono is the time elapsed from the onset of sudden
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Influence of surface layer schemes on tropical cyclone Hato (2017) intensity J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-06-30 Xiaoling Ma, Jiangnan Li, Simin Pang, Tianyun Guo, Chenghui Ding
Three surface layer schemes (MYNN, ETA, and MM5) in the Weather Research and Forecasting (WRF 4.1) model were selected to conduct simulation experiments for tropical cyclone (TC) Hato (2017). The influence of different surface layer schemes on TC intensity was compared. Although the planetary boundary layer and land surface schemes were the same, surface layer schemes minimally affected TC tracks but
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Singular spectral and control chart analysis of soil radon and thoron time series for forecasting seismic activities J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-06-28 Awais Rasheed, Muhammad Osama, Dimitrios Nikolopoulos, Muhammad Rafique
Anomalies in soil radon (222Rn) and thoron (220Rn) time series data (TSD) have been reported in many studies prior to earthquakes, suggesting both radioisotopes may serve as earthquake precursors. In the present study, periodic oscillations are being observed in measured time series of soil radon, thoron, and meteorological parameters viz., pressure, temperature, and humidity. Each time series consists
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Multi-instrument study of a spread-F event at Arecibo linked to solar wind variations J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-06-20 Salih Mehmed Bostan, Julio V. Urbina, John D. Mathews, Ross L. Dinsmore, Robert M. Robinson
Using five diverse data sets, we demonstrate that apparently local ionospheric spread-F activity, observed with an HF radar and the Arecibo Observatory (AO) Incoherent Scatter Radars (ISR) under geomagnetically quiet conditions, is likely the local manifestation of a mesoscale or larger ionospheric response to relatively weak solar wind activity. The solar wind activity included a weak pressure pulse
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Validation of precipitable water vapor estimates from an inexpensive infrared thermometer J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-06-17 Alejandro Jesús Pérez Aparicio, Javier Vaquero-Martínez, María Cruz Gallego, Manuel Antón, José Manuel Vaquero
Water vapor is a fundamental component of the Earth's atmosphere with a high spatial and temporal variability. This work studies to what extent low-cost infrared thermometers can infer precipitable water (variable commonly used to characterize atmospheric water vapor). In a calibration process, infrared thermometer readings recorded at Badajoz (Spain) during the 2015–2018 period are compared against
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Solar active region magnetic parameters and their relationship with the properties of halo coronal mass ejections J. Atmos. Sol. Terr. Phys. (IF 1.9) Pub Date : 2023-06-12 A. Shanmugaraju, P. Vijayalakshmi, M. Bendict Lawrance, Y.-J. Moon, E. Ebenezer
The coronal mass ejections (CMEs) from the sun consist of the plasma and strong magnetic fields (∼4–5 G at 1.3 R⊙) and generally, the fast CMEs are often associated with energetic particles of energy few hundreds of MeV. When the fast CMEs are ejected towards the Earth, they can disrupt the flow of solar wind in the heliosphere and impact the Earth's magnetosphere causing known space weather phenomena