Journal of Geophysical Research: Space Physics最新文献_第6页

Modes of Daily Mean Thermospheric ΣO/N2 Variability Over a Solar Cycle Observed by TIMED/GUVI 用TIMED/GUVI观测太阳周期内日平均热层ΣO/N2变率的模态

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-14 DOI: 10.1029/2024JA033384

C. E. Cantrall, Y. Zhang, L. J. Paxton, R. K. Schaefer

{"title":"Modes of Daily Mean Thermospheric ΣO/N2 Variability Over a Solar Cycle Observed by TIMED/GUVI","authors":"C. E. Cantrall, Y. Zhang, L. J. Paxton, R. K. Schaefer","doi":"10.1029/2024JA033384","DOIUrl":"https://doi.org/10.1029/2024JA033384","url":null,"abstract":"The relative column abundance of monatomic oxygen to molecular nitrogen (ΣO/N2) in the lower thermosphere has been measured for over two decades by TIMED/GUVI. This data set provides an opportunity to assess how well current empirical thermosphere climatologies reproduce observed composition variations on timescales of days to a solar cycle. Here, we characterize and compare the primary modes of daily mean thermospheric ΣO/N2 variability measured by TIMED/GUVI and generated from NRLMSIS 2.0 over a solar cycle from 2008 to 2019 using principal component analysis. The geophysical significance of these modes and their dependence on solar and geomagnetic drivers is further determined. We find that the ΣO/N2 variability over this period observed by GUVI is dominated by three distinct modes; two associated with intra-annual variations, that is, the annual and semiannual oscillations (AO and SAO), and one associated with the response to geomagnetic activity. These three modes account for 88% of the total global variability over the time period; the AO accounts for 53%, the SAO accounts for 28%, and geomagnetic activity response accounts for 7%. The separation of the AO and SAO denotes unique spatial structures and driver modulation for each of these modes. NRLMSIS 2.0 shows strong agreement with GUVI for the geomagnetic activity mode. In contrast, the two modes associated with intra-annual variations displayed different spatial structures and dependencies on solar-geomagnetic conditions, particularly solar EUV radiative flux, compared to GUVI. These results highlight important discrepancies in intra-annual variations of composition in the lower thermosphere between the NRLMSIS climatology and long-term GUVI observations.","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144281388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multi-Point Satellites Observed Dawnside Subauroral Polarization Streams (SAPS) Developed on a Short Timescale Under Weak-Storm and Non-Storm Substorm Conditions 在弱风暴和非风暴亚风暴条件下，多点卫星在短时间尺度上观测到黎明时分的亚极光极化流

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-14 DOI: 10.1029/2025JA033755

Ildiko Horvath, Brian C. Lovell

{"title":"Multi-Point Satellites Observed Dawnside Subauroral Polarization Streams (SAPS) Developed on a Short Timescale Under Weak-Storm and Non-Storm Substorm Conditions","authors":"Ildiko Horvath, Brian C. Lovell","doi":"10.1029/2025JA033755","DOIUrl":"https://doi.org/10.1029/2025JA033755","url":null,"abstract":"We study the development of the magnetosphere-ionosphere (M-I) conjugate dawnside Subauroral Polarization Streams (SAPS) by investigating the newly-formed dawnside SAPS observed soon after dawnside substorm onset. Our topside-ionosphere results show that (a) the eastward dawnside SAPS flow was weaker than the eastward auroral return flow and (b) the equatorward and downward SAPS electric (E) field components were not accompanied by any dawnside upward Region-2 field-aligned currents. These provide observational evidence that (c) the substorm current wedge (SCW) developed on the dawnside and (d) the newly-formed dawnside SAPS observed developed in a voltage generator of magnetospheric origin. Our inner-magnetosphere results show (e) the charge separation at the dawnside plasmapause, where (f) the inward (earthward) SAPS E field developed in (g) a voltage generator, (h) on a short timescale, and (i) during localized particle injections (j) associated with the dawnside SCW. From these (a–j) new results we conclude that the M-I conjugate dawnside SAPS observed developed on a short timescale, in a magnetospheric voltage generator, of which root cause was the fast development of the dawnside SCW. Our conclusion is consistent with the fast-time development of the M-I conjugate duskside SAPS, of which root cause is the fast development of the duskside SCW.","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JA033755","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144281399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Propagation Characteristics of Lightning-Generated Whistlers in the Ionosphere: Statistical and Simulation-Based Analysis 电离层中闪电哨声的传播特性：基于统计和模拟的分析

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-14 DOI: 10.1029/2024JA033546

Tian Xiang, Moran Liu, Shimin He, Xiang Xu, Shufan Zhao, Chen Zhou

{"title":"Propagation Characteristics of Lightning-Generated Whistlers in the Ionosphere: Statistical and Simulation-Based Analysis","authors":"Tian Xiang, Moran Liu, Shimin He, Xiang Xu, Shufan Zhao, Chen Zhou","doi":"10.1029/2024JA033546","DOIUrl":"https://doi.org/10.1029/2024JA033546","url":null,"abstract":"Lightning-generated whistlers (LGWs) are electromagnetic waves in the very-low-frequency band generated by lightning and propagate in the ionosphere. LGWs are an inexpensive ionospheric detection medium that can be used to reconstruct ionospheric electron density based on their dispersion characteristics. The propagation characteristics of LGWs determine their propagation paths in the ionosphere, and the correct calculation of these paths is a prerequisite for electron density inversion. Here the observations from the China Seismo-Electromagnetic Satellite in broad areas at about 500 km altitude are used to perform wave vector direction statistics and propagation characteristics analysis for fractional-hop whistlers that propagate from the Earth to the spacecraft. The propagation characteristics of whistlers are analyzed and distinguished using observational statistics of wave vector directions and simulation based on the finite difference time domain model. The results indicate that the wave normal angles of whistlers in low latitudes are significantly larger than those in mid latitudes. Low-latitude whistlers preferentially propagate obliquely outward in the magnetic meridian plane in a nonducted mode in the ionosphere. Mid-latitude whistlers may still propagate in a nonducted mode, even when their wave normal angles are relatively small. The wave normal angles of LGWs in the ionosphere show no significant longitudinal dependence and exhibit a clear latitudinal distribution pattern. The LGWs wave vector exhibits minimal vertical deviation at low and high latitudes, with significantly larger deviations near 30°N mid-latitudes. This paper reveals the propagation characteristics of LGWs in the ionosphere through observations, statistics, and simulation.","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144281422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Generation of UHR Waves as Inferred From Wave and Electron Flux Measurements by Van Allen Probes 从范艾伦探测器的波和电子通量测量推断的UHR波的产生

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-14 DOI: 10.1029/2025JA033815

D. R. Shklyar, E. E. Titova, N. S. Artekha

引用次数: 0

The Role of Cold Oxygen Ions in the EMIC Wave Growth 冷氧离子在离子波生长中的作用

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-12 DOI: 10.1029/2024JA033661

Shujie Gu, Misa Cowee, Xiangrong Fu, Lunjin Chen, Xu Liu, Vania Jordanova

{"title":"The Role of Cold Oxygen Ions in the EMIC Wave Growth","authors":"Shujie Gu, Misa Cowee, Xiangrong Fu, Lunjin Chen, Xu Liu, Vania Jordanova","doi":"10.1029/2024JA033661","DOIUrl":"https://doi.org/10.1029/2024JA033661","url":null,"abstract":"Electromagnetic ion cyclotron (EMIC) waves, driven by ring current ion temperature anisotropy in the Earth's magnetosphere, play a key role in accelerating and precipitating relativistic electrons in the radiation belts. Their excitation and saturation are significantly affected by the surrounding cold plasma. Previous studies have shown that background cold helium ions can influence the growth and saturation of EMIC waves, yet the role of cold oxygen ions in wave saturation remains less understood. In this paper, we use linear theory and nonlinear hybrid simulation to investigate the effect of cold oxygen ions in the EMIC wave growth and saturation in a homogeneous plasma containing hot and cold protons, cold helium and cold oxygen ions. Our findings reveal that increasing the cold oxygen ion concentration decreases the EMIC wave growth rate and broadens the spectral width of stop bands near the helium and oxygen gyrofrequencies. Furthermore, an increasing oxygen ion concentration notably reduces the saturation amplitude of EMIC waves in cases where the helium band is dominant, while cases with a dominant hydrogen band remain unaffected. Cold ions are heated during wave excitation, and cold helium ions are heated to keV energy, more significantly than cold protons and oxygen ions. With cold oxygen ion concentration increasing, cold helium ions take longer time to be heated to keV energy. These results offer insights into how cold plasma modifies the spectral properties and amplitudes of EMIC waves, shedding light on energy transfer from hot protons to cold plasma through EMIC waves.","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144273170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Control of Solar Wind on Magnetic Field Fluctuations in the Subsolar Magnetosheath 太阳风对亚太阳磁鞘磁场波动的控制

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-11 DOI: 10.1029/2025JA033856

Ying Zou, Brian M. Walsh, Yuxi Chen, Hongyang Zhou, Savvas Raptis

{"title":"Control of Solar Wind on Magnetic Field Fluctuations in the Subsolar Magnetosheath","authors":"Ying Zou, Brian M. Walsh, Yuxi Chen, Hongyang Zhou, Savvas Raptis","doi":"10.1029/2025JA033856","DOIUrl":"https://doi.org/10.1029/2025JA033856","url":null,"abstract":"The magnetosheath modifies the solar wind and IMF before they reach Earth's magnetosphere, and hence plays a crucial role in regulating the solar wind-magnetosphere interaction. Although the steady component of the magnetosheath magnetic field has been reasonably well reproduced, the fluctuating component has been less accounted for despite its significant amplitude. This paper empirically determines the mean characteristics of the ultra-low-frequency magnetic field fluctuations, and constructs a functional form using solar wind parameters. We use 15 years of THEMIS A data for the magnetosheath, and OMNI for the upstream solar wind conditions. Qualitatively, fluctuations are negatively correlated with the IMF cone angle, and positively with the solar wind speed and dynamic pressure. Some fluctuations are correlated with the IMF strength but not all. The level of fluctuations in the IMF is positively correlated with <0.01 Hz fluctuations in the magnetosheath. A higher Mach number is associated with a larger fraction of compressional versus transverse fluctuations in the magnetosheath. Quantitatively, the correlation between magnetosheath fluctuations and individual solar wind parameters is weak, correlation magnitude being <0.5. However, by performing a multiple linear regression fit of the solar wind parameters to magnetosheath fluctuations, a reasonably good prediction can be achieved with correlation magnitude in the range of 0.5–0.7, except for the parallel magnetosheath fluctuations of 0.01–0.1 Hz. Our results are overall consistent with earlier studies, but our quantitative approach further permits forecast of how much the IMF changes inside the magnetosheath which is beneficial for scientific understanding and space weather forecasts.","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144264655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

The Occurrence Variability of Severe Scintillation and Range Spread F From the Varying Nature of Large-to-Meso-Scale-Wave-Structures: Observations and Simulation 从大到中尺度波浪结构的变化性质看严重闪烁的发生变异性和范围扩散F：观测和模拟

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-11 DOI: 10.1029/2025JA033840

B. C. Amadi, E. A. Kherani, E. R. de Paula

{"title":"The Occurrence Variability of Severe Scintillation and Range Spread F From the Varying Nature of Large-to-Meso-Scale-Wave-Structures: Observations and Simulation","authors":"B. C. Amadi, E. A. Kherani, E. R. de Paula","doi":"10.1029/2025JA033840","DOIUrl":"https://doi.org/10.1029/2025JA033840","url":null,"abstract":"The occurrence variability on a day-to-day basis of severe S4 scintillation and range-spread F (RSF) which are the manifestations of the most robust dynamical spread F phenomenon in the nighttime equatorial-low-latitude ionosphere, remains intriguing to date. The complex nature of large-to-meso-scale-wave-structure (LSWS) that results from the two most important determining factors, large-scale pre-reversal electric field (PREF) and Meso-Scale wave electric field, poses a severe obstacle to the short-term forecasting of S4-RSF. The present study aims to investigate the competing role of the two factors by presenting S4-RSF events that occur during the summer months of 2021–2022 over the Equatorial region of Brazil. The scintillation index (S4) and total-electron-content (TEC) from the GNSS network and ionospheric drift measurements from digisonde found more frequent occurrences of severe S4-RSF during December 2021 than in January 2022. The measurements detect LSWS in both months, though December reveals phase propagation of TEC and drift oscillations for longer horizontal distances and altitudes. The strength variability of S4-RSF is understood by conducting the numerical simulation of collisional-interchange instability. In line with the observations, the simulation shows the stronger and faster equatorial plasma bubble formations from the combined action of PREF and phase-coherent mesoscale electric field. Despite the comparatively weak PREF, the stronger S4-RSF activities highlight the role of mesoscale wave electric field in defining the strength of S4-RSF.","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JA033840","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144264656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Magnetosheath Jets Associated With a Solar Wind Rotational Discontinuity in a Hybrid-Vlasov Simulation 混合- vlasov模拟中与太阳风旋转不连续有关的磁鞘喷流

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-09 DOI: 10.1029/2025JA033995

Jonas Suni, Minna Palmroth, Lucile Turc, Markus Battarbee, Yann Pfau-Kempf, Urs Ganse

{"title":"Magnetosheath Jets Associated With a Solar Wind Rotational Discontinuity in a Hybrid-Vlasov Simulation","authors":"Jonas Suni, Minna Palmroth, Lucile Turc, Markus Battarbee, Yann Pfau-Kempf, Urs Ganse","doi":"10.1029/2025JA033995","DOIUrl":"https://doi.org/10.1029/2025JA033995","url":null,"abstract":"Magnetosheath jets are transient enhancements of dynamic pressure downstream of collisionless shocks. In Earth's magnetosheath they are mostly found downstream of the quasi-parallel bow shock during steady solar wind and low interplanetary magnetic field (IMF) cone angle conditions, but they have also been observed in the quasi-perpendicular magnetosheath and during different solar wind conditions. In this study we use a 2D simulation run of the global hybrid-Vlasov model Vlasiator to investigate how the interaction between the bow shock and a solar wind rotational discontinuity influences the formation of magnetosheath jets. Separating the jets identified in the simulation based on formation site and time relative to the interaction between the discontinuity and the shock, we conduct a statistical study to find the characteristic properties of the different jet types. We find that jets forming at the quasi-parallel shock are similar to each other regardless of the stage of the shock-discontinuity interaction. Jets forming at the quasi-perpendicular shock after the discontinuity has passed are small and short-lived. The jets forming at the quasi-perpendicular shock as the discontinuity impacts it, on the other hand, merge with each other into a large and long-lived transient density enhancement that propagates deep into the magnetosheath together with the discontinuity, giving it the potential to be more geoeffective than the other types. This study sheds light on the properties of jets and jet-like structures that form during non-steady solar wind and IMF conditions, and the results can be of use when classifying similar events from spacecraft observations.","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1029/2025JA033995","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144244884","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spatio-Temporal Evolution of Mid-Latitude GPS Scintillation and Position Errors During the May 2024 Solar Storm 2024年5月太阳风暴中纬度GPS闪烁和位置误差的时空演变

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-09 DOI: 10.1029/2025JA033839

Waqar Younas, Yukitoshi Nishimura, Weixuan Liao, Josh L. Semeter, Sebastijan Mrak, Y. Jade Morton, Keith M. Groves

{"title":"Spatio-Temporal Evolution of Mid-Latitude GPS Scintillation and Position Errors During the May 2024 Solar Storm","authors":"Waqar Younas, Yukitoshi Nishimura, Weixuan Liao, Josh L. Semeter, Sebastijan Mrak, Y. Jade Morton, Keith M. Groves","doi":"10.1029/2025JA033839","DOIUrl":"https://doi.org/10.1029/2025JA033839","url":null,"abstract":"This study investigates impacts of the May 2024 superstorm on the mid-latitude Global Positioning System (GPS) scintillation and position errors. Using 1-Hz GPS receiver data, we identified position errors in PPP mode reaching up to 70 m in the Central United States during the storm main phase on May 10. The PPK solution becomes unstable following the arrival of storm and lasted till the recovery phase, coinciding with reported GPS outages of farming equipment. The large position errors were attributed to strong scintillation and carrier phase cycle slips around the equatorward boundary of the ionosphere trough, where large total electron content (TEC) gradients and irregularities were present. In the Southwestern United States, position errors of 10–20 m were associated with the storm-enhanced density and equatorial ionization anomaly. Scintillation and cycle slips in this region were minor, and bending of the GPS signal paths (refractive effect) is suggested to cause the position errors. PPP outages were also associated with sudden changes in the geometric distributions of available GPS satellites used in position calculations. On May 11, energetic particle precipitation during substorms led to abrupt jumps in TEC and scintillation, resulting in rapidly evolving position errors of up to 10 m. These findings highlight the critical role of storm-time plasma transport, precipitation, and irregularity formation in degrading GPS performance. The study underscores the need for accurate ionospheric state specification, improved signal processing technique, real-time ionospheric corrections, and optimized satellite selection algorithms, to enhance navigation resilience during severe space weather events.","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144244954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Particle-In-Cell Simulations of Starfish Prime 海星质点的细胞内粒子模拟

IF 2.6 2区地球科学

Journal of Geophysical Research: Space Physics Pub Date : 2025-06-08 DOI: 10.1029/2024JA033681

Mikhail A. Belyaev, David J. Larson, Bruce I. Cohen

{"title":"Particle-In-Cell Simulations of Starfish Prime","authors":"Mikhail A. Belyaev, David J. Larson, Bruce I. Cohen","doi":"10.1029/2024JA033681","DOIUrl":"https://doi.org/10.1029/2024JA033681","url":null,"abstract":"The Starfish Prime high altitude nuclear test created a transient diamagnetic cavity in the Earth's magnetic field above Johnston Island and launched an electromagnetic pulse (EMP) that was detected around the globe. We use the ion-kinetic particle-in-cell code Topanga to simulate diamagnetic cavity evolution and the E3 EMP signal for Starfish Prime out to over a minute of physical time. The simulation domain has a longitudinal and latitudinal extent of <math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>60</mn>\u0000 <mo>°</mo>\u0000 <mo>×</mo>\u0000 <mn>60</mn>\u0000 <mo>°</mo>\u0000 </mrow>\u0000 <annotation> $60{}^{circ}times 60{}^{circ}$</annotation>\u0000 </semantics></math> and a vertical extent of 2,000 km from the surface of the Earth. We compare our simulated results to magnetometer measurements taken in space and on the ground, finding good agreement in both cases. The diamagnetic cavity in the simulation forms in about a second, while the associated debris flux tube takes approximately 30 s to decay. The debris flux tube undergoes significant motion during this timeframe, rising upward. The measured E3 EMP signal on the ground consists of several components, all of which are present in our simulations. We discuss the physical origin of these components in relation to E3a (blast) and E3b (heave).","PeriodicalId":15894,"journal":{"name":"Journal of Geophysical Research: Space Physics","volume":"130 6","pages":""},"PeriodicalIF":2.6,"publicationDate":"2025-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144244169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0