Diptiranjan Rout, S. Patra, S. Kumar, D. Chakrabarty, G. D. Reeves, C. Stolle, K. Pandey, S. Chakraborty, E. A. Spencer
{"title":"The Growth of Ring Current/SYM‐H Under Northward IMF <i>B</i><sub><i>z</i></sub> Conditions Present During the 21–22 January 2005 Geomagnetic Storm","authors":"Diptiranjan Rout, S. Patra, S. Kumar, D. Chakrabarty, G. D. Reeves, C. Stolle, K. Pandey, S. Chakraborty, E. A. Spencer","doi":"10.1029/2023sw003489","DOIUrl":null,"url":null,"abstract":"Abstract The total energy transfer from the solar wind to the magnetosphere is governed by the reconnection rate at the magnetosphere edges as the Z‐component of interplanetary magnetic field (IMF B z ) turns southward. The geomagnetic storm on 21–22 January 2005 is considered to be anomalous as the SYM‐H index that signifies the strength of ring current, decreases and had a sustained trough value of −101 nT lasting more than 6 hr under northward IMF B z conditions. In this work, the standard WINDMI model is utilized to estimate the growth and decay of magnetospheric currents by using several solar wind‐magnetosphere coupling functions. However, it is found that the WINDMI model driven by any of these coupling functions is not fully able to explain the decrease of SYM‐H under northward IMF B z . A dense plasma sheet along with signatures of a highly stretched magnetosphere was observed during this storm. The SYM‐H variations during the entire duration of the storm were only reproduced after modifying the WINDMI model to account for the effects of the dense plasma sheet. The limitations of directly driven models relying purely on the solar wind parameters and not accounting for the state of the magnetosphere are highlighted by this work.","PeriodicalId":49487,"journal":{"name":"Space Weather-The International Journal of Research and Applications","volume":null,"pages":null},"PeriodicalIF":3.8000,"publicationDate":"2023-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Space Weather-The International Journal of Research and Applications","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1029/2023sw003489","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
Abstract The total energy transfer from the solar wind to the magnetosphere is governed by the reconnection rate at the magnetosphere edges as the Z‐component of interplanetary magnetic field (IMF B z ) turns southward. The geomagnetic storm on 21–22 January 2005 is considered to be anomalous as the SYM‐H index that signifies the strength of ring current, decreases and had a sustained trough value of −101 nT lasting more than 6 hr under northward IMF B z conditions. In this work, the standard WINDMI model is utilized to estimate the growth and decay of magnetospheric currents by using several solar wind‐magnetosphere coupling functions. However, it is found that the WINDMI model driven by any of these coupling functions is not fully able to explain the decrease of SYM‐H under northward IMF B z . A dense plasma sheet along with signatures of a highly stretched magnetosphere was observed during this storm. The SYM‐H variations during the entire duration of the storm were only reproduced after modifying the WINDMI model to account for the effects of the dense plasma sheet. The limitations of directly driven models relying purely on the solar wind parameters and not accounting for the state of the magnetosphere are highlighted by this work.
当行星际磁场的Z分量(IMF B Z)向南转变时,太阳风向磁层的总能量转移受磁层边缘重联率的控制。2005年1月21日至22日的地磁风暴被认为是异常的,因为在北向的IMF B - z条件下,表征环电流强度的SYM - H指数下降,并且持续槽值为- 101 nT,持续时间超过6小时。在这项工作中,利用标准的WINDMI模型,通过几个太阳风-磁层耦合函数来估计磁层电流的增长和衰减。然而,我们发现由这些耦合函数驱动的WINDMI模型都不能完全解释北移的IMF B z下SYM‐H的减少。在这次风暴中观测到密集的等离子体层以及高度拉伸的磁层的特征。在整个风暴期间的SYM - H变化只有在修改了WINDMI模型以考虑到致密等离子体层的影响后才能重现。直接驱动模式的局限性仅仅依赖于太阳风参数,而不考虑磁层的状态。
期刊介绍:
Space Weather: The International Journal of Research and Applications (SWE) is devoted to understanding and forecasting space weather. The scope of understanding and forecasting includes: origins, propagation and interactions of solar-produced processes within geospace; interactions in Earth’s space-atmosphere interface region produced by disturbances from above and below; influences of cosmic rays on humans, hardware, and signals; and comparisons of these types of interactions and influences with the atmospheres of neighboring planets and Earth’s moon. Manuscripts should emphasize impacts on technical systems including telecommunications, transportation, electric power, satellite navigation, avionics/spacecraft design and operations, human spaceflight, and other systems. Manuscripts that describe models or space environment climatology should clearly state how the results can be applied.