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Simulation of GPS radio occultation signals through Sporadic-E using the multiple phase screen method J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-12 Daniel W. Stambovsky; Jonah J. Colman; Omar A. Nava; Daniel J. Emmons
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Modeling drought duration and severity using two-dimensional copula J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-14 Muhammad Asif Khan; Muhammad Faisal; Muhammad Zaffar Hashmi; Amna Nazeer; Zulfiqar Ali; Ijaz Hussain
Drought is a natural disaster that has terrible effects on society and the natural environment. However, accurate detection and measurement of incoming drought events help policymakers control their severe impact by strengthening drought mitigation policies. In this research, we have assessed the suitability of various Copula's models for modeling drought events using two drought indices, i.e., Standardized
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Droplet spectral dispersion by lateral mixing process in continental deep cumulus clouds J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-22 Sudarsan Bera
In situ flight observations and theoretical analysis are used to investigate the dispersion properties of droplet size distribution (DSD) in continental deep cumulus clouds under the influence of lateral entrainment and mixing processes. The study attempts to relate the spectral width (σr) and relative dispersion (ν) of DSD with liquid water content (LWC), droplet number concentration (Nd) and mean
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Automated low-cost setup for optical and E-field records of lightning J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-22 Adonis F.R. Leal; Gabriel A.V.S. Ferreira; Andre M. Morais; Allan R.A. Manito
Lightning discharges can be detected by their electromagnetic field radiation, they can be heard for close distances (up to 20 km or so) because of the shockwaves produced by the fast expansion of the air around the plasma channel, and they can be seen by the radiation that they produced in the visible spectrum. In order to have a complete picture of this natural phenomenon, scientists around the world
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Multiscale temporal analysis and trends of relative humidity over India and Indian Ocean J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-20 Ipsita Putatunda
Moisture is one of the crucial atmospheric parameters in parameterization schemes and hence it is important to study regional moisture variation with altitude at different temporal scales. ERA-Interim and MERRA reanalysis data for 38 years (1980–2017) is analyzed to study the diurnal, seasonal, and annual variation of relative humidity (RH) with altitudes over Indian land (IND), East Equatorial Indian
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On the altitude dependence and role of zonal and meridional wind shears in the generation of E region metal ion layers J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-20 Christos Haldoupis; Sergei Shalimov
Krall et al. (2020) simulated metal ion layers in the E region ionosphere observed by the ISR at Arecibo, by considering vertical ion-motion and convergence driven by zonal and meridional winds. They report that the observed altitude structure is produced if only meridional wind forces are included in the model. Also, layer formation below 110 km, where the ions are very weakly magnetized, is supported
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Spatio-temporal and synoptic changes in dust at the three islands in the Persian Gulf region J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-11 Sara Karami; Nasim Hossein Hamzeh; Khan Alam; Faezeh Noori; Abbas Ranjbar Saadat Abadi
The occurrence of severe and inclusive dust storms has caused a lot of damage every year in the Persian Gulf region and it has destructive environmental effects in this area. The aim of this study is to investigate the monthly changes in the frequency of dust storms over Khark, Kish and Qeshm islands located in the Persian Gulf region during the 10-year period (2007–2017) using satellite and model
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Fractality of an MHD shell model for turbulent plasma driven by solar wind data: A review J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-18 Víctor Muñoz; Macarena Domínguez; Giuseppina Nigro; Mario Riquelme; Vincenzo Carbone
The Gledzer-Yamada-Ohkitani MHD shell model is used to describe dissipative events that take place in magnetized plasmas. In this review we summarize a series of works aimed to characterize the fractal features of the GOY shell model using various choices of the forcing terms, as an attempt to model the behavior of the Earth's magnetosphere driven by the solar wind. Usually, stochasticity in the shell
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Rainfall forecast based on GPS PWV together with meteorological parameters using neural network models J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-17 Ali Sam Khaniani; Hamid Motieyan; Atefeh Mohammadi
In recent years, it has been found that the Precipitable Water Vapor (PWV) time series derived from ground-based GPS measurements can be used in to forecast precipitation in different regions. However, it is inevitable to consider the impact of several meteorological parameters such as temperature, pressure, relative humidity, water vapor pressure, total cloud cover and day of year (doy) besides PWV
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Observations from the one year electric field Study-North Slope of Alaska (OYES-NSA) field campaign, and their implications for observing the distribution of global electrified cloud activity J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-06 Thomas Lavigne; Chuntao Liu; Joseph Hill; Eric Bruning
For over a century, the electric Potential Gradient (PG) of the atmosphere has been measured and studied. The local vertical electric field (Ez) is strongly influenced by the presence of lightning, electrified clouds, rainfall, aerosols, and many others. The One Year Electric Field Study-North Slope of Alaska (OYES-NSA) field campaign was established in the summer of 2017 to measure the vertical electric
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Toward a theory of ball lightning occurring in houses and aircraft J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-15 John J. Lowke; Wilfried Heil; Eugene Tam; Anthony B. Murphy
Gas discharge properties have been calculated, considering electrons, negative ions, positive ions and the metastable singlet delta oxygen molecules, to assess the possibility of ball lightning resulting from an electrical discharge. It is found that if the metastable molecules have very large densities of the order of 1017 cm−3, a stable ball-like plasma of electrons, positive ions, negative ions
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Micro-Pulse Lidar observations of elevated aerosol layers over the Himalayan region J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-04 K.K. Shukla; D.V. Phanikumar; Kondapalli Niranjan Kumar; Ashish Kumar; M. Naja; Som Sharma; Raju Attada
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The effects of the location and the timing of local convection electric field enhancements in the formation of ion multiple-nose structures J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-12 C.P. Ferradas; G.D. Reeves; B.A. Larsen; R.M. Skoug; J.-C. Zhang; H.O. Funsten; H.E. Spence
We investigate the formation of He+ and O+ multiple-nose structures observed by the Helium, Oxygen, Proton, and Electron instrument onboard Van Allen Probes A on December 2, 2012. Previous studies have suggested that multiple-nose structures can be formed by changes in the convection electric field. However, the specifics of how these changes can produce multiple-nose structures have been left unresolved
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The boundary layer height obtained by the spline numerical differentiation method using COSMIC GPS radio occultation data: A case study of the Qinghai-Tibet Plateau J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-12 Jie Xiang; Jianyin Zhou; Sixun Huang
We apply a numerical differentiation method for gradients of bending angle (BA) vertical profiles to determine the atmospheric boundary layer (ABL) height. The basic idea to obtain profiles of BA vertical gradient is to minimize an objective functional, with the Tikhonov regularization term being the second order derivative of the function to be determined; the regularization parameter is chosen as
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Modeling advective transport of radiation belt electrons J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-08 Zhao Li; Scot Elkington; Mary Hudson; Maulik Patel; Alex Boyd; John Wygant
The relativistic electron dynamics in the radiation belts falls into two categories: diffusive processes, in which particles are scattered randomly, and advective processes, in which particles are collectively driven in one direction in energy or space. In this work, we focus on advection which can occur on a timescale faster than diffusion for CME shock compressions of the dayside magnetosphere. Test-particle
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High-latitude polar pattern of ionospheric electron density: Scaling features and IMF dependence J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-07 G. Consolini; R. Tozzi; P. De Michelis; I. Coco; F. Giannattasio; M. Pezzopane; M.F. Marcucci; G. Balasis
We investigated the average polar patterns of ionospheric electron density and the corresponding patterns of scaling features as a function of interplanetary magnetic field orientation. The focus is on the Northern Hemisphere using electron density data recorded on-board ESA Swarm A satellite. The first- and second-order scaling exponents have been evaluated by means of the qth-order structure functions
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Comparative study of lightning climatology and the role of meteorological parameters over the Himalayan region J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2021-01-06 Narayan Prasad Damase; Trisanu Banik; Bapan Paul; Kumarjit Saha; Shriram Sharma; Barin Kumar De; Anirban Guha
Lightning activities are distributed asymmetrically over the globe. Satellite images show that the Himalayan region is one of the prone zones of lightning activity. We do not understand such an uneven distribution of lightning activities as of today. To elaborate on the present-day understanding of lightning flashes over the Himalayan region, we have analyzed various atmospheric factors in association
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Early main-phase electrodynamics of the ring current inferred from DMSP J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-10 William J. Burke; Pei-Chen Lai
This paper exploits capabilities implicit in DMSP plasma and field data through which users may infer local IGRF magnetic fields (B→0), as well as components of magnetic perturbations (δB→⊥) and plasma drift (V→⊥) vectors perpendicular toB→0. We use relations between V→⊥ andδB→⊥, associated with Region 2 (R-2) field-aligned currents (FACs), consistent with Faraday's law, to determine Alfvénic reflection
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Generation of magnetic field in the low-latitude ionosphere by tsunami wave J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-11 V.M. Sorokin; A.K. Yaschenko
The travel of a tsunami wave is accompanied by generation of geomagnetic field perturbation and acoustic-gravity wave (AGW) propagating into the ionosphere. We consider a mechanism of electric current generation by the tsunami wave in the ocean and ionosphere. The electric current in the ocean is generated by motion of conducting seawater in geomagnetic field, and in the conducting ionosphere it is
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Study of aerosol vertical distribution during meteor showers of January 2009 J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-15 Pratibha B. Mane; Dhairyasheel B. Mane
Atmospheric aerosols are minute particles (1 nm–100 μm) suspended in various layers of the Earth's atmosphere. During meteor showers, huge amount of cosmic debris called meteoroids enters into the Earth's atmosphere. These particles contribute to aerosols in the mesosphere and lower thermosphere. The aerosols emerged from meteor dust particles are having different size. The displacement of the particles
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Principal component analysis in the modeling of HILDCAAs during the Solar Minimum of Cycle 23/24 J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-14 Virginia Klausner; Isabelle Cristine Pellegrini Lamin; Arian Ojeda-González; Humberto Gimenes Macedo; Claudia Maria Nicoli Cândido; Alan Prestes; Marina Vedelago Cezarini
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Nighttime O(1D) and corresponding Atmospheric Band emission (762 nm) derived from rocket-borne experiment J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-15 Mykhaylo Grygalashvyly; Boris Strelnikov; Martin Eberhart; Jonas Hedin; Mikhail Khaplanov; Jörg Gumbel; Markus Rapp; Franz-Josef Lübken; Stefan Löhle; Stefanos Fasoulas
Based on common volume rocket-borne measurements of temperature, densities of atomic oxygen and neutral air, we derived O(1D) nighttime concentrations and corresponding Atmospheric band emission (762 nm). This is one of the first retrievals of the nighttime O(1D) concentration. Recently, Kalogerakis, Sharma and co-workers have suggested a new production path of O(1D) based on the reaction of vibrationally
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PMC observations from the OMPS Limb Profiler J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-09 Matthew T. DeLand; Nick Gorkavyi
We present new observations of polar mesospheric clouds (PMCs) from the Ozone Mapping and Profiler Suite (OMPS) Limb Profiler (LP) instrument. The OMPS LP limb scattering measurements provide altitude-resolved PMC observations with full global coverage from 2012 to the present. Relative PMC brightness observed by OMPS LP varies between hemispheres due to changes in viewing geometry, consistent with
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“Strange” particles and micro-sized ball lightning in some electric discharges J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-18 Anatoly I. Nikitin; Vadim A. Nikitin; Alexander M. Velichko; Tamara F. Nikitina
When conducting experiments on the electric explosion of titanium foil in water, a “strange” radiation was detected, leaving dotted traces on the film. The velocity of the carriers of this radiation was estimated as 20–40 m/s, and their energy, estimated by the Coulomb drag mechanism, turned out to be equal to 700 MeV. Subsequently, it was found that similar traces are formed at various types of high-current
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Tropical tropopause layer evolution during 2015–16 El Niño event inferred from COSMIC RO measurements J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-01 Saginela Ravindra Babu; Yuei-An Liou
The detailed evolution of different tropical tropopause layer (TTL) parameters, such as tropopause height (cold point (CPH)/lapse rate (LRH)/convective (COH)), its corresponding temperature (CPT/LRT/COT) and TTL thickness in response to recent 2015–16 El Niño event are delineated using high-resolution Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) Radio Occultation
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Winds and tides of the Antarctic mesosphere and lower thermosphere: One year of meteor-radar observations over Rothera (68°S, 68°W) and comparisons with WACCM and eCMAM J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-11-27 Shaun M. Dempsey; Neil P. Hindley; Tracy Moffat-Griffin; Corwin J. Wright; Anne K. Smith; Jian Du; Nicholas J. Mitchell
Atmospheric tides play a critical role in the dynamics and coupling of mesosphere and lower-thermosphere (MLT). Global Circulation Models (GCMs) that aim to span the lower, middle and upper atmosphere must therefore be capable of reproducing the tides and observations of tides are thus crucial to constrain the models. Here we present the first climatology of the 12- and 24-h tides measured at heights
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Impact of aerosols on surface ozone during COVID-19 pandemic in southern India: A multi-instrumental approach from ground and satellite observations, and model simulations J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-09 Raja Obul Reddy Kalluri; Balakrishnaiah Gugamsetty; Chakradhar Rao Tandule; Rama Gopal Kotalo; Lokeswara Reddy Thotli; Ramakrishna Reddy Rajuru; Surya Nagi Reddy Palle
The World Health Organization (WHO) declared the coronavirus disease of 2019 (COVID-19) as a pandemic due to its widespread global infection. This has resulted in lockdown under different phases in many nations, including India, around the globe. In the present study, we report the impact of aerosols on surface ozone in the context of pre-lockdown (01st - 24th March 2020 (PLD)), lockdown phase1 (25th
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Determination of vortex current structure in the high-latitude ionosphere with associated GIC bursts from ground magnetic data J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-11 V.E. Chinkin; A.A. Soloviev; V.A. Pilipenko; M.J. Engebretson; YaA. Sakharov
The rapid changes of magnetic fields dB/dt that excite large geomagnetically induced currents (GICs) may be associated with quasi-periodic impulsive disturbances of the geomagnetic field with ~10–15 min duration (Ps6 pulsations). The paper proposes a data processing technique for a 2D array of magnetic stations that automatically recognizes eddy current structures in the polar ionosphere and evaluates
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Statistical study on sporadic sodium layers (SSLs) based on diurnal sodium lidar observations at Beijing, China (40.5 °N, 116 °E) J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-09 Yuan Xia; Satonori Nozawa; Jing Jiao; Jihong Wang; Faquan Li; Xuewu Cheng; Yong Yang; Lifang Du; Guotao Yang
Sporadic sodium layers (SSLs) have been observed all over the globe and always has been of great concern. However, most researches on SSLs are based on only nocturnal observations due to strong daytime solar background noise, thus there is still insufficient understanding of the diurnal variation of SSLs. In this paper, a statistical analysis of SSLs observed by a diurnal sodium (Na) lidar at Beijing
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Climatology of the short-period (8-h and 6-h) tides observed by meteor radars at Tromsø and Svalbard J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-13 D. Pancheva; P. Mukhtarov; C. Hall; A.K. Smith; M. Tsutsumi
The paper presents climatology of the poorly known, particularly at high latitudes, short-period (8- and 6-h) tides observed by meteor radars at high latitudinal stations Tromsø (70°N, 19°E) and Svalbard (78°N, 16°E) based on 16 years (2003–2018) and 18 years (2001–2018) of measurements, respectively. The main focus of this study is to clarify the seasonal variability and vertical structure of the
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A new method to subtract dayglow for auroral observation of SSUSI in LBH ranges based on the improved AURIC J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-10 JiaKe Wang; GuangXing Ding; Miao Yu; HaiFeng Wang
A new method to remove the dayglow components for auroral observations from the Special Sensor Ultraviolet Spectrographic Imager (SSUSI) aboard the Defense Meteorological Satellite Program (DMSP) F16 in Lyman-Birge-Hopfield (LBH) ranges based on the improved Atmospheric Ultraviolet Radiance Integrated Code (AURIC) algorithm is proposed in this study. This method is developed by determining the coefficients
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Analysis of nighttime OH vibrational excited states production rate J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-07 Mohammed Amin Ferdi; Mourad Djebli
Hydroxyl vibrational excited states OH∗ in the Earth’s ionosphere are investigated numerically in the presence of suprathermal electrons. The latter are included by using a Boltzmann equation numerical solver and a numerical cross-section for electron impact with OH. We have found that important changes in the peak altitude of OH∗ occur when geomagnetic activities vary. In addition, nighttime changes
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Long-term trend and solar cycle in the middle atmosphere temperature revealed from merged HALOE and SABER datasets J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-09 Tao Li; Jia Yue; James M. Russell; Xi Zhang
The middle atmosphere temperature trend and solar cycle have been studied with long-term ground-based and satellite datasets and/or model simulations. Single satellite observations for middle atmosphere temperature are not long enough (less than 2 solar cycles) to derive long-term trend and solar cycle effects with great confidence. Using a nearly 30-year dataset merged from the Halogen Occultation
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Relations among eruptive prominence properties, flare evolution and CME kinematics in large solar energetic particle events J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-10 K. Koleva; M. Dechev; P. Duchlev
We report a detailed study of the relationship between solar filament eruption, flare productivity and CME kinematics relevant to Solar Energetic Particle (SEP) events. We analyze kinematics and morphological behaviors of 32 filament eruptions appearing during the Solar Cycle 24, between Aug 14, 2010 and April 18, 2016. For our analysis a high resolution data in different Extreme Ultraviolet (EUV)
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Multi-instrument observations of SCIPS: 1. ISR and GPS TEC results J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-10 Ross Dinsmore; J.D. Mathews; Anthea Coster; R.M. Robinson; Sumanta Sarkhel; Philip J. Erickson; Julio Urbina
An uninterrupted multi-day (6–8 May 2013) ionospheric F-region event with features indicative of medium-scale traveling ionospheric disturbances (MSTIDs) was detected with the Millstone Hill (MH) incoherent scatter radar (ISR). It was later identified, with the addition of Global Positioning System total electron content (GPS-TEC) imaging, as a novel ionospheric phenomenon. This phenomenon is herein
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High intensity lightning recognition system using Very Low Frequency signal features J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-12-09 N.S. Arshad; M. Abdullah; S.A. Samad; N. Abdullah
Commercial lightning detection networks offer detailed lightning stroke data upon subscription. Alternatively, the lightning monitoring system can be deployed at lower cost using Very Low Frequency (VLF) signal reception. With that, a dual-class high-intensity lightning recognition algorithm was developed using VLF signal features to identify the severity of lightning occurrence in the vicinity of
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Adiabatic and non-adiabatic evolution of relativistic electrons in the heart of the outer radiation belt during the 1 June 2013 geomagnetic storm J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-11-19 M. Stepanova; V.A. Pinto; E.E. Antonova
The adiabatic and non-adiabatic behavior of relativistic electrons in the outer radiation belt during the 1 June 2013 geomagnetic storm is studied using data from the Van Allen Probes and THEMIS missions. Analysis of the evolution of the plasma pressure shows that the pressure increased by one order of magnitude during the storm reaching a maximum value towards the end or slightly after the main phase
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On the seasonal evolution of the diurnal pattern of the longitudinal structures in MAVEN NGIMS derived CO2 densities over martian upper atmosphere J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-11-18 Mridula N; Manju G
An analysis on the longitudinal structures in the martian upper atmospheric CO2 densities during the 33rd Martian year (earth year: 2015–2017) is reported herein. The CO2 densities in the altitude region of 165–220 km corresponding to the in-bound periapsis orbits of MAVEN NGIMS during different martian seasons have been considered for this study. The data used spans over a longitude region of −180°
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Simulation study on the effect of atmosphere-ocean-wave interactions on Typhoon Rammasun (2014) in the South China Sea J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-11-17 Junying Sun; Jiangnan Li; Zixi Ruan; Kailu Wu; Fangzhou Li
The paper implemented a “standard” coupling system in the South China Sea without any further development avoiding to add a new parameterization on ocean-atmosphere-wave interaction. The sea and the waves influenced tropical cyclone (TC) through the interaction between the air and sea fluxes. The performance of the fully coupled atmosphere-ocean-wave model is overall better that of the uncoupled model
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Dissipation of acoustic-gravity waves in the Earth’s thermosphere J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-11-16 A.K. Fedorenko; E.I. Kryuchkov; O.K. Cheremnykh; Y.A. Selivanov
The dissipation of acoustic-gravity waves in the thermosphere due to molecular viscosity and thermal conductivity based on a modified system of hydrodynamic equations is studied. A modification of the system of equations consists in additional taking into account in the linearized Navier–Stokes equations and heat transfer additional terms describing the transfer of momentum and energy due to the background
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Qualitative observations of the cirrus clouds effect on the thermal structure of the tropical tropopause J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-09-26 Saleem Ali; Sanjay Kumar Mehta; Vanmathi Annamalai; Aravindhavel Ananthavel; Ramesh Reddy
An attempt has been made to understand the effect of the cirrus clouds on the tropical tropopause thermal structure over a tropical station Gadanki (13.45oN, 79.2oE) using regular radiosonde observation at 12:00Z and CALIPSO measurements at the closest proximity to Gadanki during 2006–2013. As the CALIPSO and radiosonde observation timings are not simultaneous, we considered only those cases when cirrus
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Assessing the impact of middle atmosphere observations on day-to-day variability in lower thermospheric winds using WACCM-X J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-11-11 Fabrizio Sassi; John P. McCormack; Jennifer L. Tate; David D. Kuhl; Nancy L. Baker
Recent studies have shown that day-to-day variability in thermospheric winds (100–300 km altitude) driven by meteorological variability from below affects ionospheric E and lower F regions, highlighting the need for accurate, continuous specification of day-to-day variability throughout the entire atmosphere for geospace weather prediction systems. To better understand the nature of forcing from below
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Substorm onset and development: The crucial role of flow channels J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-31 Larry R. Lyons; Yukitoshi Nishimura
In this paper, we described the basic features and observations bases of the scenario for the substorm expansion phase that we have developed from our research over the past ~10 years. Onset occurs along magnetic field lines of the inner proton plasma sheet, and is first seen in the aurora as beading along the onset aurora arc, which lies near the equatorward boundary of the auroral oval. Growth of
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ENSO-related impact on the vapor sources of China based on case simulations of summer 2015 and 2010 J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-31 Fangzhou Li; Wenshi Lin; Jiangnan Li
ENSO has significant impact on the precipitation pattern in summer over China. To differentiate the different impacts from El Niño and La Nina, two groups of experiments were conducted using WRF-Chem CO tracer model, with one group for summer 2015 and the other group for summer 2010. The study explained the difference between 2015 and 2010 as strong El Niño and La Nina, respectively, with a perspective
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Ionization effect in the Earth’s atmosphere during the sequence of October–November 2003 Halloween GLE events J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-27 A.L. Mishev; P.I.Y. Velinov
The effect of precipitating high-energy particles on atmospheric physics and chemistry is extensively studied over the last decade. In majority of the existing models, the precipitating particles induced ionization plays an essential role. For such effects, it is necessary to possess enhanced increase in ion production, specifically during the winter period. In this study, we focus on highly penetrating
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Distinguishing different lightning events based on wavelet packet transform of magnetic field signals J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-20 Shiye Huang; Weiqi Kong; Jing Yang; Qilin Zhang; Nianpeng Yao; Bingzhe Dai; Jiaying Gu
In this paper, the wavelet packet transform (WPT) is applied to analyze the time-frequency features of three kinds of lightning events (the cloud pulse, the return stroke and the stepped leader) and a new identification method based on WPT is proposed. The magnetic-field data used in this paper were recorded by Nanjing Lightning Location Network in 2018. Firstly, the wavelet spectra of three typical
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Ozone variability: Influence by its precursors and meteorological parameters- an investigation J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-08 Asuri Lakshmi Kanchana; Vijay Kumar Sagar; Mahesh Pathakoti; D.V. Mahalakshmi; Kapanaboina Mallikarjun; Biswadip Gharai
Surface observations on trace gases such as ozone (O3), oxides of nitrogen (August 2014–May 2017) and carbon monoxide (January 2016–May 2017) were used to investigate O3 chemistry. Study shows O3 concentration is high during winter with a mean value of 35.54 ± 7.16 ppbv and low concentration in monsoon with a mean value of 12.70 ± 3.55 ppbv. Oxides of nitrogen (NOx = NO + NO2) concentrations are high
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First observation of atmospheric electric field at Kashmir valley North Western Himalayas, Srinagar (India) J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-21 Shaista Afreen; N. Jeni Victor; Gowher Bashir; Sagarika Chandra; Nissar Ahmed; Devendraa Siingh; R.P. Singh
Preliminary results from the measurement of potential gradient (PG) for the period of March 2018–February 2019 at the University of Kashmir, Srinagar, (34° 03′ N, 74° 51’ E, 1585 m amsl) India is reported. The annual mean diurnal variation of PG represents typical double-maxima pattern with the primary maximum at 0900–1000 LT and the secondary maximum at 1900–2000 LT which is in accordance with the
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Improving the ionospheric model accuracy using artificial neural network J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-17 K.A. Sidorenko; A.N. Kondratyev
Information on the state of the ionosphere is of great importance for organizing communications in the short-wave range. One of the main methods for estimating the ionosphere parameters is the use of modeling. Most existing ionosphere models rely on the algorithms presented in the recommendations of the Radiocommunication Sector of the International Telecommunications Union. This work shows one of
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Temporal evolution of atmospheric parameter-profiling on rain height over two geoclimatic regions in Nigeria J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-19 Y.B. Lawal; S.E. Falodun; J.S. Ojo
This work studies the temporal variation of rain heights in the Sub-Sahelian and Coastal regions of Nigeria using six (6) years Tropical Rain Measuring Mission Precipitation Radar (TRMM-PR) reprocessed data retrieved from the Global Precipitation Measurement (GPM) constellation Satellites and Era-Interim Field of the European Centre for Medium-Range Weather Forecast (ECMWF). The research reveals seasonal
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A study of ionospheric irregularities with spatial fluctuation of TEC J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-24 Guanyi Ma; Qi Li; Jinghua Li; Qingtao Wan; Jiangtao Fan; Xiaolan Wang; Takashi Maruyama; Jie Zhang
Ionospheric irregularities are small-scale disturbances in the ionosphere which disrupt radio waves by causing amplitude and phase scintillations. Global Navigation Satellite System (GNSS) network can work as two-dimensional array to provide the spatial structure of the irregularities. With derived vertical total electron content (VTEC), we propose a spatial fluctuation of TEC (SFT) parameter to identify
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An investigation of mid-latitude ionospheric peak in TEC using the TIEGCM J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-20 Chunhua Jiang; Wenbin Wang; Guobin Yang; Jing Liu; Zhengyu Zhao
A local maximum value of ionospheric total electron content (TEC) in midlatitude regions, named midlatitude ionospheric peak in this study, has been frequently observed during both the daytime and nighttime. We have carried out a modeling study of midlatitude ionospheric peaks in TEC using the Thermosphere Ionosphere Electrodynamic General Circulation Model (TIEGCM) to investigate possible mechanisms
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Spatial features of geomagnetic cutoff rigidity secular variation using analytical approaches J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-20 Emanuel S. Comedi; Ana G. Elias; Bruno S. Zossi
The secular variation spatial pattern of geomagnetic cutoff rigidity, Rc, is analyzed considering analytical expressions. Störmer analytic Rc equation in terms of geomagnetic latitude is used considering a pure dipolar field for the centered and eccentric dipole coordinates, together with a dipole-quadrupole superposition simplified equation. Linear Rc time trend for the period 1900–2020 in a 5 ° × 15 °
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A synergy of linear model and wavelet analysis towards space-time characterization of aerosol optical depth (AOD) during pre-monsoon season (2007–2016) over Indian sub-continent J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-20 Gunadhar Barik; Prasenjit Acharya; Arabinda Maiti; Bijoy Krishna Gayen; Somnath Bar; Ashis Sarkar
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Universal time control of the parameters of the electron temperature enhancement zone in the winter subauroral ionosphere J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-09-28 Innokentiy Golikov; Artem Gololobov; Dmitry Baishev
Comparison of the numerical simulation results with experimental data obtained aboard the CHAMP spacecraft has shown that in the eastern longitudes during the local winter period the parameters of electron temperature (Te) enhancement zone in the subauroral ionosphere undergo significant changes depending on the universal time (UT control) as a result of the formation of the shadow region, almost devoid
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Thermospheric gravity wave characteristics in the daytime over low-latitudes during geomagnetic quiet and disturbed conditions J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-10 Subir Mandal; Duggirala Pallamraju
The importance of gravity waves (GWs) in the redistribution of energy and momentum in the Earth's atmosphere is well known. It is extremely important to understand the nature of variation in the GW characteristics to address issues of coupling in the Earth's atmosphere. We have used digisonde measurements to investigate the variation in thermospheric wave dynamics in the daytime over low-latitudes
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Scattering by whistler-mode waves during a quiet period perturbed by substorm activity J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-28 J.-F. Ripoll; M.H. Denton; D.P. Hartley; G.D. Reeves; D. Malaspina; G.S. Cunningham; O. Santolík; S.A. Thaller; V. Loridan; J.F. Fennell; D.L. Turner; W.S. Kurth; C.A. Kletzing; M.G. Henderson; A.Y. Ukhorskiy
We study the dynamics of radiation belt electrons during a 10-day quiet period perturbed by substorm activity and preceding a high-speed stream (HSS), aiming at a global description of the radiation belts in L-shell, L in [2, 6], and energy [0.1, 10] MeV. We combine Van Allen Probes observations and Fokker-Planck numerical simulations of pitch-angle diffusion. The Fokker-Planck model uses event-driven
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Ultra-low frequency (ULF) magnetic field emissions associated with some major earthquakes occurred in Indian Subcontinent J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-10 Swati; Birbal Singh; Devbrat Pundhir; Ashwini K. Sinha; K. Madhusudan Rao; Anirban Guha; Yashuhide Hobara
We have analyzed ULF magnetic field emissions data obtained from identical 3- component search coil magnetometers installed at Indian stations of Agra (Geograph. lat. 27.2°N, long. 78°E), Shillong (25.92oN, 91.88oE), and Kachchh (23.78oN, 71oE) for the months of April 2012 and September 2013 in which three major earthquakes occurred, one of magnitude M = 8.5 in Indonesian region and two of magnitudes
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Forecasting long-term solar activity with time series models: Some cautionary findings J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-11 Gordon Reikard
Long-term forecasting of solar activity, over a scale of centuries, is of interest in modeling climate. Reconstructions of solar irradiance based on radionuclides span 9.4 to 11.5 millennia. There is evidence of multiple maxima and minima, as well as changes in trend. Analysis of the data yields ambiguous results. Fourier spectra find long cycles in the data, but these are not confirmed in the time
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Atmospheric electric field variations during fair weather and thunderstorms at different altitudes J. Atmos. Sol. Terr. Phys. (IF 1.503) Pub Date : 2020-10-10 Hripsime Mkrtchyan; Gayane Karapetyan; Davit Aslanyan
Ground-based electric field measurements during fair weather and thunderstorms are key parameters for Global Electric Circuit investigations and climate change assessment. We study the variations of near surface electric field during fair weather and thunderstorms. In this work we present daily, monthly and yearly distribution of thunderstorm activity from 2012 to 2019 at different research stations