Earth, Planets and Space最新文献

{"title":"Plasma structuring within an expanded polar cap and cusp studied with the SS-520-3 sounding rocket.","authors":"L M Buschmann, K Asamura, L B N Clausen, Y Jin, H Kojima, A Kumamoto, S Kurita, Y Ogawa, K Oksavik, Y Saito, A Spicher, S Yokota, W J Miloch","doi":"10.1186/s40623-025-02189-7","DOIUrl":"https://doi.org/10.1186/s40623-025-02189-7","url":null,"abstract":"<p><strong>Abstract: </strong>The SS-520-3 sounding rocket was launched on November 4th, 2021 as part of the Grand Challenge Initiative - Cusp from Ny-Ålesund, Svalbard. The rocket was launched into the cusp ionosphere during the main phase of a geomagnetic storm. In this study we utilize two low energy particle analyzers as well as a multi-needle Langmuir probe and an impedance probe as part of the rocket payload. This study aims to provide an overview of the flight conditions from a range of ground-based instruments and scintillation receivers. We were able to confirm that the rocket entered the cusp through the poleward edge at around <math><msup><mn>74</mn> <mo>∘</mo></msup> </math> of northern geographic latitude. Additionally, the rocket encountered polar cap patches (PCP), as well as a patch within the cusp (CP) and a newly-formed tongue of ionisation (TOI). Analysis of the density variations within different scale sizes show enhancements within meter-size and kilometer-size scales on the edges of PCP, within the CP and TOI. Overall, the enhancements within the variations on all sizes, as well as enhancements of the electron density were significantly higher within the CP and TOI in comparison to the PCP, though all structures were encountered at similar altitudes. The strongest enhancements were found on the poleward edge of the TOI, corresponding to strong fluctuations within the electron density. The TOI also had the largest enhancements within gradients of kilometer-size in comparison to meter-sizes. As the TOI is convecting with respect to the background plasma, the edges are susceptible to instabilities like the Kelvin-Helmholtz instability (KHI) and Gradient-Drift instability (GDI), giving rise to plasma density structures on several scale sizes.</p><p><strong>Graphical abstract: </strong></p>","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"77 1","pages":"76"},"PeriodicalIF":3.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12106493/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144173128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coseismic crustal seismic velocity changes associated with the 2024 M_W 7.5 Noto earthquake, Japan.","authors":"Nicolas Paris, Yuji Itoh, Florent Brenguier, Qing-Yu Wang, Yixiao Sheng, Tomomi Okada, Naoki Uchida, Quentin Higueret, Ryota Takagi, Shin'ichi Sakai, Satoshi Hirahara, Shuutoku Kimura","doi":"10.1186/s40623-025-02177-x","DOIUrl":"https://doi.org/10.1186/s40623-025-02177-x","url":null,"abstract":"<p><p> The 2024 <math><msub><mtext>M</mtext> <mtext>w</mtext></msub> </math> 7.5 Noto earthquake, Japan, was preceded by an intense seismic swarm thought to be driven by upward fluid migration. Crustal seismic velocities vary with external perturbations caused by earthquakes, and the presence of pressurized fluids in the crust amplifies the resulting coseismic velocity change. Hence, we characterize subsurface fluid by measuring the coseismic velocity change associated with the 2024 mainshock. For this purpose, we perform multi-frequency-band ambient noise seismic interferometry using data from permanent and temporary seismic stations. Significant coseismic velocity drops are observed, with an average decrease of about 0.5% inside the Noto peninsula, reaching 0.6-0.8% in the regions near the coseismic slip peaks. The observed velocity drops inside the peninsula correlate well with the modeled static-stress-change-induced velocity drops and peak ground velocity (PGV) and acceleration (PGA) as proxies of dynamic stress change. However, their respective contribution to the observed coseismic velocity drop remains unclear because of the similarities in their spatial pattern. Outside the Noto Peninsula, the observed velocity drops average around 0.1%, which is predominantly attributed to dynamic stress changes from passing waves because modeled static stress changes are negligible at these great distances. Although the addition of temporary stations significantly increases the resolution of the velocity drop measurements in the pre-mainshock swarm zone, our results exhibit no large velocity drop anomaly in this region, suggesting that the amount of pressurized fluids in the shallow crust down to <math><mo>∼</mo></math> 2.5 km depth is not anomalously large. This implies that the upward migration of fluids preceding the mainshock is likely confined to greater depths.</p><p><strong>Graphical abstract: </strong></p><p><strong>Supplementary information: </strong>The online version contains supplementary material available at 10.1186/s40623-025-02177-x.</p>","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"77 1","pages":"51"},"PeriodicalIF":3.0,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12011933/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143958620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Three-dimensional velocity structure models in and around the Kathmandu Valley, Central Nepal","authors":"Kazuki Koketsu, Haruhiko Suzuki, Yujia Guo","doi":"10.1186/s40623-023-01954-w","DOIUrl":"https://doi.org/10.1186/s40623-023-01954-w","url":null,"abstract":"","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"11 8","pages":"1-11"},"PeriodicalIF":3.0,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139380198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance of the double-thin-shell approach for studying nighttime medium-scale traveling ionospheric disturbances using two dense GNSS observation networks in Japan","authors":"Weizheng Fu, Yuichi Otsuka, A. Shinbori, M. Nishioka, S. Perwitasari","doi":"10.1186/s40623-023-01956-8","DOIUrl":"https://doi.org/10.1186/s40623-023-01956-8","url":null,"abstract":"","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"42 2","pages":"1-16"},"PeriodicalIF":3.0,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139379922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel high accuracy finite-difference time-domain method","authors":"Harune Sekido, Takayuki Umeda","doi":"10.1186/s40623-023-01934-0","DOIUrl":"https://doi.org/10.1186/s40623-023-01934-0","url":null,"abstract":"","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"27 3","pages":"1-20"},"PeriodicalIF":3.0,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139384092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geomagnetic relative paleointensity and direction during the last 40,000 years obtained from a sediment core in the Nankai Trough","authors":"Ryoya Goto, T. Yamazaki, N. Okutsu, J. Ashi","doi":"10.1186/s40623-023-01945-x","DOIUrl":"https://doi.org/10.1186/s40623-023-01945-x","url":null,"abstract":"","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"22 10","pages":"1-17"},"PeriodicalIF":3.0,"publicationDate":"2024-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139389391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can we explain the post-2015 absence of the Chandler wobble?","authors":"Ryuji Yamaguchi, Masato Furuya","doi":"10.1186/s40623-023-01944-y","DOIUrl":"https://doi.org/10.1186/s40623-023-01944-y","url":null,"abstract":"","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"109 44","pages":"1-10"},"PeriodicalIF":3.0,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139390933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A systematic scheme to develop dynamic earthquake rupture scenarios: a case study on the Wenchuan–Maoxian Fault in the Longmen Shan, China, thrust belt","authors":"Rongjiang Tang, Ryosuke Ando","doi":"10.1186/s40623-023-01932-2","DOIUrl":"https://doi.org/10.1186/s40623-023-01932-2","url":null,"abstract":"","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"8 3","pages":"1-18"},"PeriodicalIF":3.0,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139391553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"\u0000 \u0000 \u0000 \u0000 $$textrm{O}^+$$\u0000 \u0000 \u0000 O\u0000 +\u0000 \u0000 \u0000 density distribution in the nightside ionosphere reconstructed from ISS-IMAP/EUVI data","authors":"Shin’ya Nakano, Y. Hozumi, A. Saito, I. Yoshikawa, Atsushi Yamazaki, Kazuo Yoshioka, G. Murakami","doi":"10.1186/s40623-023-01947-9","DOIUrl":"https://doi.org/10.1186/s40623-023-01947-9","url":null,"abstract":"","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"113 28","pages":"1-18"},"PeriodicalIF":3.0,"publicationDate":"2024-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139390942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relation between magnetopause position and reconnection rate under quasi-steady solar wind dynamic pressure.","authors":"Hyangpyo Kim, Hyunju Kim Connor, Ying Zou, Jaeheung Park, Rumi Nakamura, Kathryn McWilliams","doi":"10.1186/s40623-024-02101-9","DOIUrl":"10.1186/s40623-024-02101-9","url":null,"abstract":"<p><p>The lunar environment heliospheric X-ray imager (LEXI) and solar wind-magnetosphere-ionosphere link explorer (SMILE) will observe the magnetopause motion in soft X-rays to understand dayside reconnection modes as a function of solar wind conditions after their respective launches in the near future. To support their successful science mission, we investigate the relationship between the magnetopause position and the dayside reconnection rate by utilizing super dual auroral radar network (SuperDARN) observations and widely used empirical models of magnetopause position (Shue et al. in J Geophys Res 103:17691-17700. 10.1029/98JA01103, 1998 and Lin et al. in J Geophys Res 115:A04207. 10.1029/2009JA014235, 2010). We select three cases when the interplanetary magnetic field rotates during periods of quasi-steady solar wind dynamic pressure. We first estimate the dayside reconnection rate by calculating the electric field along the open-closed magnetic field boundary (OCB) in the OCB moving reference frame. Then, we estimate the magnetopause position near the local noon by inputting NASA OMNI solar wind data into the empirical magnetopause models. The reconnection rate shows anti-correlation with the magnetopause position that it generally increases as the magnetopause located closer to Earth and vice versa. Our result also confirms that the reconnection rate increases as the empirical coupling efficiency between solar wind and the magnetosphere increases.</p><p><strong>Graphical abstract: </strong></p><p><strong>Supplementary information: </strong>The online version contains supplementary material available at 10.1186/s40623-024-02101-9.</p>","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"76 1","pages":"165"},"PeriodicalIF":3.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11655602/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142876633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}