Space Weather最新文献_第8页

Machine Learning-Based Emulator for the Physics-Based Simulation of Auroral Current System 基于机器学习的极光电流系统物理模拟器

IF 3.7 2区地球科学

Space Weather Pub Date : 2024-01-02 DOI: 10.1029/2023sw003720

Ryuho Kataoka, Aoi Nakamizo, Shinya Nakano, Shigeru Fujita

{"title":"Machine Learning-Based Emulator for the Physics-Based Simulation of Auroral Current System","authors":"Ryuho Kataoka, Aoi Nakamizo, Shinya Nakano, Shigeru Fujita","doi":"10.1029/2023sw003720","DOIUrl":"https://doi.org/10.1029/2023sw003720","url":null,"abstract":"Using a machine learning technique called echo state network (ESN), we have developed an emulator to model the physics-based global magnetohydrodynamic simulation results of REPPU (REProduce Plasma Universe) code. The inputs are the solar wind time series with date and time, and the outputs are the time series of the ionospheric auroral current system in the form of two-dimensional (2D) patterns of field-aligned current, potential, and conductivity. We mediated a principal component analysis for a dimensionality reduction of the 2D map time series. In this study, we report the latest upgraded Surrogate Model for REPPU Auroral Ionosphere version 2 (SMRAI2) with significantly improved resolutions in time and space (5 min in time, ∼1° in latitude, and 4.5° in longitude), where the dipole tilt angle is also newly added as one of the input parameters to reproduce the seasonal dependence. The fundamental dependencies of the steady-state potential and field-aligned current patterns on the interplanetary magnetic field directions are consistent with those obtained from empirical models. Further, we show that the ESN-based emulator can output the AE index so that we can evaluate the performance of the dynamically changing results, comparing with the observed AE index. Since the ESN-based emulator runs a million times faster than the REPPU simulation, it is promising that we can utilize the emulator for the real-time space weather forecast of the auroral current system as well as to obtain large-number ensembles to achieve future data assimilation-based forecast.","PeriodicalId":22181,"journal":{"name":"Space Weather","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139079549","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

Forward-Looking Study of Solar Maximum Impact in 2025: Effects of Satellite Navigation Failure on Aviation Network Operation in the Greater Bay Area, China 2025 年太阳活动最大影响的前瞻性研究：卫星导航故障对中国粤港澳大湾区航空网络运行的影响

IF 3.7 2区地球科学

Space Weather Pub Date : 2023-12-27 DOI: 10.1029/2023sw003678

Dabin Xue, Jian Yang, Zhizhao Liu, Wei Cong

{"title":"Forward-Looking Study of Solar Maximum Impact in 2025: Effects of Satellite Navigation Failure on Aviation Network Operation in the Greater Bay Area, China","authors":"Dabin Xue, Jian Yang, Zhizhao Liu, Wei Cong","doi":"10.1029/2023sw003678","DOIUrl":"https://doi.org/10.1029/2023sw003678","url":null,"abstract":"Satellite navigation based on the Global Navigation Satellite System can provide aircraft with more precise guidance and increase flight efficiency. However, severe space weather events can cause satellite navigation failure due to the dramatic increase in total electron content and irregularities in the ionosphere. Consequently, ground navigation has to be used to replace satellite navigation, increasing aircraft separation standards and reducing airspace capacity. As a result, numerous flights may be delayed or even canceled, incurring significant financial losses. The occurrence peak of space weather events generally coincides with the 11-year-cycle solar maximum, and 2025 is expected to be the upcoming solar maximum. The Greater Bay Area (GBA), located in the equatorial ionization anomaly region of China, is particularly vulnerable to space weather impacts. To explore the effects of satellite navigation failure on flight operation, we conduct this looking-forward study and propose solution methods from the standpoint of Air Traffic Management, by simulating satellite navigation failure scenarios. Based on the projected flight volume in 2025 related to the GBA airports, simulation results show that the economic costs can be tens of millions of Euros, which is dependent on the duration of satellite navigation failure and the time interval of ground navigation-based landing. We believe that this study can be a benchmark for evaluating the potential economic effects of forthcoming space weather on flight operations.","PeriodicalId":22181,"journal":{"name":"Space Weather","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139055411","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

Atmospheric Ionizations by Solar X-Rays, Solar Protons, and Radiation Belt Electrons in September 2017 Space Weather Event 2017 年 9 月空间天气事件中太阳 X 射线、太阳质子和辐射带电子对大气的电离作用

IF 3.7 2区地球科学

Space Weather Pub Date : 2023-12-27 DOI: 10.1029/2023sw003651

Kiyoka Murase, Ryuho Kataoka, Takanori Nishiyama, Kaoru Sato, Masaki Tsutsumi, Yoshimasa Tanaka, Yasunobu Ogawa, Tatsuhiko Sato

{"title":"Atmospheric Ionizations by Solar X-Rays, Solar Protons, and Radiation Belt Electrons in September 2017 Space Weather Event","authors":"Kiyoka Murase, Ryuho Kataoka, Takanori Nishiyama, Kaoru Sato, Masaki Tsutsumi, Yoshimasa Tanaka, Yasunobu Ogawa, Tatsuhiko Sato","doi":"10.1029/2023sw003651","DOIUrl":"https://doi.org/10.1029/2023sw003651","url":null,"abstract":"Energetic particles from space deposit their energies on the Earth's atmosphere and contribute to variations in the concentration of neutral components such as ozone which controls the atmospheric temperature balance. Comprehensive understandings of their global impact on the atmosphere require whole pictures of spatiotemporal ionization distributions due to them. We first attempt to evaluate and summarize the altitude profiles of ionization for the September 2017 space weather event with cutting-edge space-borne and ground-based observations of different types of particle inputs. In early September 2017, the Sun showed notable activity, including X-class flares and solar proton events. During this period, ground-based radar observations have confirmed atmospheric ionization events by energetic particle precipitations of solar flare X-rays, solar protons, and radiation belt electrons, the main sources of ionization into the Earth's atmosphere. We estimate the altitude profiles of the ionization rate by using the Particle and Heavy Ion Transport code System (PHITS) with the input of the particle fluxes obtained by satellites. The estimates are then compared with measurements of the ionization altitude, ionization intensity, and electron density by the radars in the polar region, such as the PANSY radar at Syowa Station and the EISCAT in Tromsø, Norway. We conclude that the PHITS simulation results reasonably reproduce (within the error of a factor of two) those ionizations measured by ground-based instruments with inputs of observed ionization sources by satellites.","PeriodicalId":22181,"journal":{"name":"Space Weather","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139057710","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

Analysis of the Geoelectric Field in Sweden Over Solar Cycles 23 and 24: Spatial and Temporal Variability During Strong GIC Events 太阳周期 23 和 24 期间的瑞典地电场分析：强烈 GIC 事件期间的空间和时间变异性

IF 3.7 2区地球科学

Space Weather Pub Date : 2023-12-27 DOI: 10.1029/2023sw003588

V. Lanabere, A. P. Dimmock, L. Rosenqvist, L. Juusola, A. Viljanen, A. Johlander, E. Odelstad

{"title":"Analysis of the Geoelectric Field in Sweden Over Solar Cycles 23 and 24: Spatial and Temporal Variability During Strong GIC Events","authors":"V. Lanabere, A. P. Dimmock, L. Rosenqvist, L. Juusola, A. Viljanen, A. Johlander, E. Odelstad","doi":"10.1029/2023sw003588","DOIUrl":"https://doi.org/10.1029/2023sw003588","url":null,"abstract":"Geomagnetic storms can produce large perturbations on the Earth magnetic field. Through complex magnetosphere-ionosphere coupling, the geoelectric field (E) and geomagnetic field (B) are highly perturbed. The E is the physical driver of geomagnetically induced currents. However, a statistical study of the E in Sweden has never been done before. We combined geomagnetic data from the International Monitor for Auroral Geomagnetic Effects network in Northern Europe with a 3-D structure of Earth's electrical conductivity in Sweden as the input of a 1-D model to compute the E between 2000 and 2018. Northwestern Sweden presents statistically larger E magnitudes due to larger |dB/dt| variations in the north than in the south of Sweden and relative lower conductivity in the west compared to central and eastern Sweden. In contrast, the 15 strongest daily maximum |E| events present more frequently a maximum magnitude in central Sweden (62.25°N) and their relative strengths are not the same for all latitudes. These results highlight the different regional response to geomagnetic storms, which can be related to ground conductivity variability and the complex magnetosphere-ionosphere coupling mechanisms.","PeriodicalId":22181,"journal":{"name":"Space Weather","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139055455","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

Horizontal Spatial Correlation of the Ionospheric Day-To-Day Variations at Low Latitudes Based on GOLD Nmax Data 基于 GOLD Nmax 数据的低纬度电离层日间变化的水平空间相关性

IF 3.7 2区地球科学

Space Weather Pub Date : 2023-12-27 DOI: 10.1029/2023sw003627

Jiawen Chen, Jiahao Zhong, Yongqiang Hao, Xin Wan, Qiaoling Li, Zijing Tang, Xingyan Song, Hao Han, Kang Wang, Jiawei Kuai, Aojun Ren

{"title":"Horizontal Spatial Correlation of the Ionospheric Day-To-Day Variations at Low Latitudes Based on GOLD Nmax Data","authors":"Jiawen Chen, Jiahao Zhong, Yongqiang Hao, Xin Wan, Qiaoling Li, Zijing Tang, Xingyan Song, Hao Han, Kang Wang, Jiawei Kuai, Aojun Ren","doi":"10.1029/2023sw003627","DOIUrl":"https://doi.org/10.1029/2023sw003627","url":null,"abstract":"Peak electron density data derived from GOLD measurements during 2018–2022 are used to analyze the magnitudes and correlations of ionospheric diurnal variability at low latitudes. The correlation distance describes the correlations between spatial locations and is defined in this paper as the angular separation at which the correlation coefficient decreases from 1 to 0.7. Variations in correlation distance with local time, season, magnetic latitude, solar activity, and geomagnetic activity are discussed in this study. The average value of the zonal correlation distance is approximately 8.55° and 3.56° for the meridional direction at low geomagnetic latitudes (magnetic latitudes <30°). The statistical results indicate that both zonal and meridional correlation distances vary little with local time premidnight, while they show pronounced seasonal and latitudinal variations. Both zonal and meridional correlation distances increase with increasing solar activity and decrease with enhancing geomagnetic activity. The EIA strength and gradient mainly modulate the distributions of correlation distances related to magnetic latitude, season, and solar flux level. An empirical model is constructed to describe the temporal and spatial variations in the correlation distance at low latitudes. The study of correlation distances would contribute to a better understanding of ionospheric variability and improvements in data assimilation.","PeriodicalId":22181,"journal":{"name":"Space Weather","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139055410","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

RAM-SCB Runs on Request at CCMC RAM-SCB 应要求在 CCMC 运行

IF 3.7 2区地球科学

Space Weather Pub Date : 2023-12-26 DOI: 10.1029/2023sw003771

Steven K. Morley, Vania K. Jordanova, Yihua Zheng, Maksym Petrenko

引用次数: 0

Modeling Pipe to Soil Potentials From Geomagnetic Storms in Gas Pipelines in New Zealand 新西兰天然气管道地磁暴引起的管道到土壤电位建模

IF 3.7 2区地球科学

Space Weather Pub Date : 2023-12-19 DOI: 10.1029/2023sw003601

Tim Divett, Malcolm Ingham, Gemma Richardson, Mark Sigley, Craig J. Rodger

{"title":"Modeling Pipe to Soil Potentials From Geomagnetic Storms in Gas Pipelines in New Zealand","authors":"Tim Divett, Malcolm Ingham, Gemma Richardson, Mark Sigley, Craig J. Rodger","doi":"10.1029/2023sw003601","DOIUrl":"https://doi.org/10.1029/2023sw003601","url":null,"abstract":"Gas pipelines can experience elevated pipe to soil potentials (PSPs) during geomagnetic disturbances due to the induced geoelectric field. Gas pipeline operators use cathodic protection to keep PSPs between −0.85 and −1.2 V to prevent corrosion of the steel pipes and disbondment of the protective coating from the pipes. We have developed a model of the gas pipelines in the North Island of New Zealand to identify whether a hazard exists to these pipelines and how big this hazard is. We used a transmission line representation to model the pipelines and a nodal admittance matrix method to calculate the PSPs at nodes up to 5 km apart along the pipelines. We used this model to calculate PSPs resulting from an idealized 100 mVkm−1 electric field, initially to the north and east. The calculated PSPs are highest are at the ends of the pipelines in the direction of the applied electric field vector. The calculated PSP follows a characteristic curve along the length of the pipelines that matches theory, with deviations due to branchlines and changes in pipeline direction. The modeling shows that the PSP magnitudes are sensitive to the branchline coating conductance with higher coating conductances decreasing the PSPs at most locations. Enhanced PSPs produce the highest risk of disbondment and corrosion occurring, and hence this modeling provides insights into the network locations most at risk.","PeriodicalId":22181,"journal":{"name":"Space Weather","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138824138","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

Radio Absorption in the Nightside Ionosphere of Mars During Solar Energetic Particle Events 太阳高能粒子事件期间火星夜侧电离层的无线电吸收

IF 3.7 2区地球科学

Space Weather Pub Date : 2023-12-19 DOI: 10.1029/2023sw003755

Y. Harada, Y. Nakamura, B. Sánchez-Cano, M. Lester, N. Terada, F. Leblanc

{"title":"Radio Absorption in the Nightside Ionosphere of Mars During Solar Energetic Particle Events","authors":"Y. Harada, Y. Nakamura, B. Sánchez-Cano, M. Lester, N. Terada, F. Leblanc","doi":"10.1029/2023sw003755","DOIUrl":"https://doi.org/10.1029/2023sw003755","url":null,"abstract":"Characterization, understanding, and prediction of the Martian radio environment are of increasing importance to the forthcoming human exploration of Mars. Here we investigate 3–5 MHz radio absorption in the nightside ionosphere of Mars caused by enhanced ionization at <100 km altitudes during solar energetic particle (SEP) events. We conduct a quantitative analysis of radio absorption and SEP flux data that have been accumulated by two spacecraft currently orbiting Mars, thereby demonstrating that radio absorption is clearly correlated with SEP fluxes. A comparison of the observations with radio absorption properties predicted by a numerical model indicates that the relative temporal changes, radio frequency dependence, and SEP energy dependence of the observed radio absorption are in agreement with the model prediction. Meanwhile, the model systematically overestimates the radio absorption in the ionosphere by a factor of 3.7. We explore several sources of uncertainty, including the electron-neutral collision frequency, absolute sensitivity of the SEP instrument, and limited transport of SEPs to the atmosphere, but the ultimate cause of the systematic discrepancy between the measured and modeled radio absorption is yet to be identified. Further efforts should be put into the development of a comprehensive and observationally validated model of radio absorption in the Martian ionosphere to assist the future crew and spacecraft activities on the surface of Mars.","PeriodicalId":22181,"journal":{"name":"Space Weather","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138824204","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

Topside Electron Density Modeling Using Neural Network and Empirical Model Predictions 利用神经网络和经验模型预测进行顶层电子密度建模

IF 3.7 2区地球科学

Space Weather Pub Date : 2023-12-19 DOI: 10.1029/2023sw003501

S. Dutta, M. B. Cohen

{"title":"Topside Electron Density Modeling Using Neural Network and Empirical Model Predictions","authors":"S. Dutta, M. B. Cohen","doi":"10.1029/2023sw003501","DOIUrl":"https://doi.org/10.1029/2023sw003501","url":null,"abstract":"We model the electron density in the topside of the ionosphere with an improved machine learning (ML) model and compare it to existing empirical models, specifically the International Reference Ionosphere (IRI) and the Empirical-Canadian High Arctic Ionospheric Model (E-CHAIM). In prior work, an artificial neural network (NN) was developed and trained on two solar cycles worth of Defense Meteorological Satellite Program data (113 satellite-years), along with global drivers and indices to predict topside electron density. In this paper, we highlight improvements made to this NN, and present a detailed comparison of the new model to E-CHAIM and IRI as a function of location, geomagnetic condition, time of year, and solar local time. We discuss precision and accuracy metrics to better understand model strengths and weaknesses. The updated neural network shows improved mid-latitude performance with absolute errors lower than the IRI by 2.5 × 109 to 2.5 × 1010 e−/m3, modestly improved performance in disturbed geomagnetic conditions with absolute errors reduced by about 2.5 × 109 e−/m3 at high Kp compared to the IRI, and high Kp percentage errors reduced by >50% when compared to E-CHAIM.","PeriodicalId":22181,"journal":{"name":"Space Weather","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2023-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139029985","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

Space Weather in the Popular Media, and the Opportunities the Upcoming Solar Maximum Brings 大众媒体中的太空天气，以及即将到来的太阳活动高峰带来的机遇

IF 3.7 2区地球科学

Space Weather Pub Date : 2023-12-15 DOI: 10.1029/2023sw003819

Brett A. Carter, Noé Lugaz, Steven K. Morley, Jennifer Gannon, Shasha Zou, Huixin Liu

引用次数: 0