Abstract Many active volcanoes and various types of seismic activities exist in the southern part of the Northeast Japan subduction zone. One of the geologically most interesting features in this area is the sequential explosive eruptions of a group of volcanoes. The group consists of Mt. Azuma and Mt. Adatara on the volcanic front line, Mt. Bandai west of the volcanic front, and Mt. Numazawa on the back-arc side. A previous petrological study on the eruption products regarded Mt. Numazawa as an anomalous back-arc volcano because its lavas are similar to those of volcanoes on the volcanic front. The reason behind this unique connection was unclear, and hence, this study was intended to understand the deep fluids distribution beneath the area. For this purpose, a 3-D regional electrical resistivity structure was estimated from a series of wide-band magnetotelluric surveys, with 45 observation points deployed from the fore-arc to the back-arc sides. The most important feature of the resistivity structure is a large conductive zone in the central part of the area, spanning from the upper mantle to the lower crust. Interestingly, the lateral elongation of the conductor is oblique to the volcanic front line and consistent with the spatial distribution of the group of volcanoes and the low-frequency earthquake clusters around them. Therefore, the conductor most likely represents a large, elongated magmatic fluid reservoir beneath the volcanoes. Hydrous partial melting might be the cause of the enhanced conductivity. Graphical Abstract
{"title":"On a large magmatic fluid reservoir oblique to the volcanic front in the southern part of NE Japan revealed by the magnetotelluric survey","authors":"Dieno Diba, Makoto Uyeshima, Masahiro Ichiki, Shin’ya Sakanaka, Makoto Tamura, Yiren Yuan, Marceau Gresse, Yusuke Yamaya, Yoshiya Usui","doi":"10.1186/s40623-023-01899-0","DOIUrl":"https://doi.org/10.1186/s40623-023-01899-0","url":null,"abstract":"Abstract Many active volcanoes and various types of seismic activities exist in the southern part of the Northeast Japan subduction zone. One of the geologically most interesting features in this area is the sequential explosive eruptions of a group of volcanoes. The group consists of Mt. Azuma and Mt. Adatara on the volcanic front line, Mt. Bandai west of the volcanic front, and Mt. Numazawa on the back-arc side. A previous petrological study on the eruption products regarded Mt. Numazawa as an anomalous back-arc volcano because its lavas are similar to those of volcanoes on the volcanic front. The reason behind this unique connection was unclear, and hence, this study was intended to understand the deep fluids distribution beneath the area. For this purpose, a 3-D regional electrical resistivity structure was estimated from a series of wide-band magnetotelluric surveys, with 45 observation points deployed from the fore-arc to the back-arc sides. The most important feature of the resistivity structure is a large conductive zone in the central part of the area, spanning from the upper mantle to the lower crust. Interestingly, the lateral elongation of the conductor is oblique to the volcanic front line and consistent with the spatial distribution of the group of volcanoes and the low-frequency earthquake clusters around them. Therefore, the conductor most likely represents a large, elongated magmatic fluid reservoir beneath the volcanoes. Hydrous partial melting might be the cause of the enhanced conductivity. Graphical Abstract","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135817633","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}
Pub Date : 2023-09-21DOI: 10.1186/s40623-023-01901-9
Yoshiaki Tamura, Takahito Kazama, Ryuichi Nishiyama, Koji Matsuo, Yuichi Imanishi
Abstract Postseismic gravity changes after the 2011 Tohoku earthquake (Mw9.0) were investigated using the data from superconducting gravimeters (SGs) at Mizusawa, Japan. The data in the period from 2014 to 2021 were used in the analysis. The SG data were first corrected for instrumental drift using the results of absolute gravity measurements. Then, correction for the hydrological effect was applied based on physical modeling of soil moisture. Finally, the effect of vertical displacement of the station (free-air effect) was corrected using GNSS data. After these corrections, residual gravity indicated a long-term increase, with its rate gradually decreasing with time. This fact suggests that viscoelastic relaxation after the earthquake played an important role in producing the long-term gravity changes. Fitting a decaying exponential function of time to the residual series yielded 89.4 ± 4.4 µGal (1 µGal = 10 –8 ms –2 ) as the total gravity change and 635 ± 17 days as the characteristic time scale. In addition to the ground-based observations, the data from satellite gravity missions GRACE/GRACE-FO were analyzed to retrieve gravity changes at Mizusawa. Similar analysis of the satellite-based data yielded 15.2 ± 1.6 µGal as the total gravity change and 3444 ± 599 days as the characteristic time scale. The difference in the estimates of the total gravity change, of a factor of about 6, from the ground-based and the satellite-based observations may be attributed to the limited spatial resolution in the latter method. The difference in the estimates of the time scale, of a factor of about 1/5, may originate from the difference in the depth where the two kinds of gravimetry are mainly sensitive. Referring to recent theoretical studies on postseismic deformations after the 2011 Tohoku earthquake, our results can be interpreted consistently by assuming the existence of a layer of viscoelastic materials with viscosity $$2times {10}^{18} text{Pa s}$$ 2×1018Pa s underneath the Tohoku area of Japan. Graphical Abstract
利用日本水泽超导重力仪(SGs)的数据研究了2011年日本东北地震(Mw9.0)后的重力变化。分析使用了2014年至2021年期间的数据。SG数据首先使用绝对重力测量结果对仪器漂移进行了校正。然后，在土壤水分物理模拟的基础上对水文效应进行校正。最后，利用GNSS数据对台站垂直位移的影响(自由空气效应)进行校正。经过这些修正后，剩余重力呈现出长期增加的趋势，其速率随时间逐渐减小。这一事实表明，地震后粘弹性松弛在产生长期重力变化中起了重要作用。对残差序列进行时间衰减指数函数拟合，总重力变化为89.4±4.4µGal(1µGal = 10 -8 ms -2)，特征时间尺度为635±17天。除了地面观测外，还分析了GRACE/GRACE- fo卫星重力任务的数据，以检索水泽的重力变化。对卫星数据进行类似分析，总重力变化为15.2±1.6µGal，特征时间尺度为3444±599天。地面观测和卫星观测对总重力变化的估计相差约6倍，这可归因于后者方法的空间分辨率有限。时间尺度估计的差异约为1/5，这可能源于两种重力法主要敏感的深度差异。结合近年来有关2011年东北地震震后形变的理论研究，我们的研究结果可以通过假设日本东北地区地下存在黏度为$$2times {10}^{18} text{Pa s}$$ 2 × 10 18 Pa s的粘弹性材料层来得到一致的解释。图形摘要
{"title":"Postseismic gravity changes after the 2011 Tohoku earthquake observed by superconducting gravimeters at Mizusawa, Japan","authors":"Yoshiaki Tamura, Takahito Kazama, Ryuichi Nishiyama, Koji Matsuo, Yuichi Imanishi","doi":"10.1186/s40623-023-01901-9","DOIUrl":"https://doi.org/10.1186/s40623-023-01901-9","url":null,"abstract":"Abstract Postseismic gravity changes after the 2011 Tohoku earthquake (Mw9.0) were investigated using the data from superconducting gravimeters (SGs) at Mizusawa, Japan. The data in the period from 2014 to 2021 were used in the analysis. The SG data were first corrected for instrumental drift using the results of absolute gravity measurements. Then, correction for the hydrological effect was applied based on physical modeling of soil moisture. Finally, the effect of vertical displacement of the station (free-air effect) was corrected using GNSS data. After these corrections, residual gravity indicated a long-term increase, with its rate gradually decreasing with time. This fact suggests that viscoelastic relaxation after the earthquake played an important role in producing the long-term gravity changes. Fitting a decaying exponential function of time to the residual series yielded 89.4 ± 4.4 µGal (1 µGal = 10 –8 ms –2 ) as the total gravity change and 635 ± 17 days as the characteristic time scale. In addition to the ground-based observations, the data from satellite gravity missions GRACE/GRACE-FO were analyzed to retrieve gravity changes at Mizusawa. Similar analysis of the satellite-based data yielded 15.2 ± 1.6 µGal as the total gravity change and 3444 ± 599 days as the characteristic time scale. The difference in the estimates of the total gravity change, of a factor of about 6, from the ground-based and the satellite-based observations may be attributed to the limited spatial resolution in the latter method. The difference in the estimates of the time scale, of a factor of about 1/5, may originate from the difference in the depth where the two kinds of gravimetry are mainly sensitive. Referring to recent theoretical studies on postseismic deformations after the 2011 Tohoku earthquake, our results can be interpreted consistently by assuming the existence of a layer of viscoelastic materials with viscosity $$2times {10}^{18} text{Pa s}$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:mrow> <mml:mn>2</mml:mn> <mml:mo>×</mml:mo> <mml:msup> <mml:mrow> <mml:mn>10</mml:mn> </mml:mrow> <mml:mn>18</mml:mn> </mml:msup> <mml:mtext>Pa s</mml:mtext> </mml:mrow> </mml:math> underneath the Tohoku area of Japan. Graphical Abstract","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136235753","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}
Abstract Kirishima volcano consists of more than 20 eruptive centers. Among them, Shinmoe-dake had magmatic eruptions in October 2017 and March 2018. Subsequently, another active cone, Iwo-yama, had phreatic eruptions in April 2018. These events were unique in that the 2018 eruption was the first effusion-dominated eruption of Shinmoe-dake and the first simultaneous activity of two cones of the Kirishima volcanic group ever documented. We report the detailed sequence of the events by combining areal photos, satellite images, and seismo-acoustic data analyses with the other published information. The seismo-acoustic data clarify the eruption onset and the transitions of the behaviors in three stages for each of the 2017 and 2018 eruptions. For both eruptions, we present regularly repeated tremors or ’drumbeat’ earthquakes in the second stage, which interpret as gas separation from magma, leading to the ash-poor plume in the 2017 eruption or the effusive eruption in the 2018 event. We also propose that the 2017 and 2018 eruptions of Shinmoe-dake and the 2018 eruption of Iwo-yama are sequential events linked by the degassing of magma beneath Shinmoe-dake. An eruption like the 2017–2018 eruptions of Shinmoe-dake would leave few geological records and could be captured only by modern techniques. Although Shinmoe-dake has been believed to be an example of less-frequent eruptions, effusive eruptions like the 2018 case might have occurred more frequently in the past , but the following eruptions had obscured their records. The timelines summarized in this study will be useful in future studies of Kirishima volcanoes and world equivalences. Graphical Abstract
{"title":"The sequence of the 2017–2018 eruptions and seismo-acoustic activity at Kirishima volcano group","authors":"Mie Ichihara, Tsukasa Kobayashi, Fukashi Maeno, Takao Ohminato, Atsushi Watanabe, Setsuya Nakada, Takayuki Kaneko","doi":"10.1186/s40623-023-01883-8","DOIUrl":"https://doi.org/10.1186/s40623-023-01883-8","url":null,"abstract":"Abstract Kirishima volcano consists of more than 20 eruptive centers. Among them, Shinmoe-dake had magmatic eruptions in October 2017 and March 2018. Subsequently, another active cone, Iwo-yama, had phreatic eruptions in April 2018. These events were unique in that the 2018 eruption was the first effusion-dominated eruption of Shinmoe-dake and the first simultaneous activity of two cones of the Kirishima volcanic group ever documented. We report the detailed sequence of the events by combining areal photos, satellite images, and seismo-acoustic data analyses with the other published information. The seismo-acoustic data clarify the eruption onset and the transitions of the behaviors in three stages for each of the 2017 and 2018 eruptions. For both eruptions, we present regularly repeated tremors or ’drumbeat’ earthquakes in the second stage, which interpret as gas separation from magma, leading to the ash-poor plume in the 2017 eruption or the effusive eruption in the 2018 event. We also propose that the 2017 and 2018 eruptions of Shinmoe-dake and the 2018 eruption of Iwo-yama are sequential events linked by the degassing of magma beneath Shinmoe-dake. An eruption like the 2017–2018 eruptions of Shinmoe-dake would leave few geological records and could be captured only by modern techniques. Although Shinmoe-dake has been believed to be an example of less-frequent eruptions, effusive eruptions like the 2018 case might have occurred more frequently in the past , but the following eruptions had obscured their records. The timelines summarized in this study will be useful in future studies of Kirishima volcanoes and world equivalences. Graphical Abstract","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136310711","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}
Abstract We infer the temporal changes in the pressure sources that induced crustal deformation during the 2018 Shinmoe-dake eruption using strain and tilt observations and discern that the deep magmatic activity associated with the early stage of this eruption began approximately 19 h earlier than the previously defined onset of magmatic activity. Distinct tilt changes were observed from around 09:00 on 6 March to 12:00 on 8 March 2018 (JST), coincident with observed lava outflow into the crater and lava dome formation. Existing studies have attributed this tilt change to the onset of the deflation of a spherical pressure source located at ~ 7 km bsl (below sea level) to the northwest of Shinmoe-dake. Here we examine strain and tilt data that were acquired in the Kirishima volcanic group, and we find that the distinct changes in the measured strain at Isa-Yoshimatsu Observatory began at around 14:00 on 5 March. This change can be explained by the deflation of a spherical pressure source, thereby suggesting that the onset of magma ascent was earlier than previously thought. The time variation in the spherical pressure source is estimated using the time-dependent inversion of the Ensemble Kalman Filter; the deflation source ascended from ~ 11 to 7 km bsl during Phase 1 (14:00 on 5 March to 06:00 on 6 March) and descended from 7 to 8 km bsl during Phase 2 (06:00 on 6 March to 12:00 on 8 March). Interferometric synthetic aperture radar analysis suggests that a dike intrusion had occurred just below Shinmoe-dake crater until 5 March, and this inflatable crustal deformation is attributed to the emplacement of residual volcanic fluids from the 2011 eruption. It is also known that the surface eruptive activity increased during Phase 1, including an increase in ash venting from the night of 5 March. These strain and tilt observations, therefore, suggest that magma ascended from ~ 11 km bsl to the magma reservoir at 7 km bsl during Phase 1, followed by a deflation of the magma reservoir during Phase 2 due to the large magma supply to the surface. Graphical Abstract
摘要利用应变和倾斜观测资料推断了2018年Shinmoe-dake火山喷发期间引起地壳变形的压力源的时间变化，并发现与此次火山喷发早期相关的深部岩浆活动开始时间比之前定义的岩浆活动开始时间早约19 h。从2018年3月6日09:00到2018年3月8日12:00 (JST)，观察到明显的倾斜变化，与观察到的熔岩流入火山口和熔岩穹窿形成一致。现有的研究将这种倾斜变化归因于位于新茂湖西北方向约7 km bsl(海平面以下)的球形压力源的开始收缩。本文对雾岛火山群的应变和倾斜数据进行了分析，发现伊沙吉松天文台的应变测量值在3月5日14:00左右开始发生明显变化。这种变化可以用一个球形压力源的收缩来解释，从而表明岩浆上升的开始时间比以前认为的要早。利用集合卡尔曼滤波器的时变反演估计了球面压力源的时变;在第1阶段(3月5日14:00至3月6日06:00)，紧缩源从每小时11公里上升至每小时7公里，在第2阶段(3月6日06:00至3月8日12:00)，紧缩源从每小时7公里下降至每小时8公里。干涉合成孔径雷达分析表明，在3月5日之前，Shinmoe-dake火山口下方曾发生过岩脉侵入，这种可膨胀的地壳变形归因于2011年火山喷发后残留的火山流体的侵入。据了解，地表喷发活动在第一阶段有所增加，包括从3月5日夜间开始的火山灰喷发。因此，这些应变和倾斜观测表明，在第1阶段，岩浆从~ 11 km bsl上升到7 km bsl的岩浆库，随后在第2阶段，由于大量岩浆向地表供应，岩浆库出现了收缩。图形抽象
{"title":"Subsurface magma movement inferred from extensometer and tiltmeter records during the early stage of the 2018 Shinmoe-dake eruptions, Japan","authors":"Koki Yoshinaga, Takeshi Matsushima, Hiroshi Shimizu, Yusuke Yamashita, Ken’ichi Yamazaki, Shintaro Komatsu, Satoshi Fujiwara","doi":"10.1186/s40623-023-01895-4","DOIUrl":"https://doi.org/10.1186/s40623-023-01895-4","url":null,"abstract":"Abstract We infer the temporal changes in the pressure sources that induced crustal deformation during the 2018 Shinmoe-dake eruption using strain and tilt observations and discern that the deep magmatic activity associated with the early stage of this eruption began approximately 19 h earlier than the previously defined onset of magmatic activity. Distinct tilt changes were observed from around 09:00 on 6 March to 12:00 on 8 March 2018 (JST), coincident with observed lava outflow into the crater and lava dome formation. Existing studies have attributed this tilt change to the onset of the deflation of a spherical pressure source located at ~ 7 km bsl (below sea level) to the northwest of Shinmoe-dake. Here we examine strain and tilt data that were acquired in the Kirishima volcanic group, and we find that the distinct changes in the measured strain at Isa-Yoshimatsu Observatory began at around 14:00 on 5 March. This change can be explained by the deflation of a spherical pressure source, thereby suggesting that the onset of magma ascent was earlier than previously thought. The time variation in the spherical pressure source is estimated using the time-dependent inversion of the Ensemble Kalman Filter; the deflation source ascended from ~ 11 to 7 km bsl during Phase 1 (14:00 on 5 March to 06:00 on 6 March) and descended from 7 to 8 km bsl during Phase 2 (06:00 on 6 March to 12:00 on 8 March). Interferometric synthetic aperture radar analysis suggests that a dike intrusion had occurred just below Shinmoe-dake crater until 5 March, and this inflatable crustal deformation is attributed to the emplacement of residual volcanic fluids from the 2011 eruption. It is also known that the surface eruptive activity increased during Phase 1, including an increase in ash venting from the night of 5 March. These strain and tilt observations, therefore, suggest that magma ascended from ~ 11 km bsl to the magma reservoir at 7 km bsl during Phase 1, followed by a deflation of the magma reservoir during Phase 2 due to the large magma supply to the surface. Graphical Abstract","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136310275","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}
Pub Date : 2023-09-19DOI: 10.1186/s40623-023-01894-5
Tshimangadzo Merline Matamba, Donald W. Danskin, Rendani R. Nndanganeni, Mpho Tshisaphungo
Abstract The ionosphere suffers major perturbations during severe space weather events such as Coronal Mass Ejections (CMEs), solar flares, high-speed streams, and Corotating Interaction Regions (CIRs). The ionosphere can experience depletions or enhancements in Total Electron Content (TEC) during severe space weather conditions. The South African National Space Agency (SANSA) near-real-time (NRT) TEC maps were used to show the ionospheric variability during the geomagnetic storm of 3–8 Nov 2021 over the southern Africa mid-latitude region. The ionosonde TEC, NRT TEC, and the quiet-time AfriTEC model were compared during the 6-day period. A negative ionospheric response was observed during the main and recovery phases of the geomagnetic storm (4–5 Nov 2021). The changes to neutral composition O/N 2 was one of the physical processes attributed to the decrease in TEC over the mid-latitude region. The GPS TEC maps showed a very good agreement with ionosonde measurements and the AfriTEC model. A strong east–west TEC gradient was observed occurring between two ionosonde stations. Graphical Abstract
{"title":"Space weather impacts on the ionosphere over the southern African mid-latitude region","authors":"Tshimangadzo Merline Matamba, Donald W. Danskin, Rendani R. Nndanganeni, Mpho Tshisaphungo","doi":"10.1186/s40623-023-01894-5","DOIUrl":"https://doi.org/10.1186/s40623-023-01894-5","url":null,"abstract":"Abstract The ionosphere suffers major perturbations during severe space weather events such as Coronal Mass Ejections (CMEs), solar flares, high-speed streams, and Corotating Interaction Regions (CIRs). The ionosphere can experience depletions or enhancements in Total Electron Content (TEC) during severe space weather conditions. The South African National Space Agency (SANSA) near-real-time (NRT) TEC maps were used to show the ionospheric variability during the geomagnetic storm of 3–8 Nov 2021 over the southern Africa mid-latitude region. The ionosonde TEC, NRT TEC, and the quiet-time AfriTEC model were compared during the 6-day period. A negative ionospheric response was observed during the main and recovery phases of the geomagnetic storm (4–5 Nov 2021). The changes to neutral composition O/N 2 was one of the physical processes attributed to the decrease in TEC over the mid-latitude region. The GPS TEC maps showed a very good agreement with ionosonde measurements and the AfriTEC model. A strong east–west TEC gradient was observed occurring between two ionosonde stations. Graphical Abstract","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135063888","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}
Abstract We introduce a new flexible one-dimensional photochemical model named Photochemical and RadiatiOn Transport model for Extensive USe (PROTEUS), which consists of a Python graphical user interface (GUI) program and Fortran 90 modules. PROTEUS is designed for adaptability to many planetary atmospheres, for flexibility to deal with thousands of or more chemical reactions with high efficiency, and for intuitive operation with GUI. Chemical reactions can be easily implemented into the Python GUI program in a simple string format, and users can intuitively select a planet and chemical reactions on GUI. Chemical reactions selected on GUI are automatically analyzed by string parsing functions in the Python GUI program, then applied to the Fortran 90 modules to simulate with the selected chemical reactions on a selected planet. We performed a benchmark test of PROTEUS to confirm its validity, by applying it to the Martian atmosphere and the Jovian ionosphere. PROTEUS can significantly save the time for those who need to develop a new photochemical model; users just need to write chemical reactions in the Python GUI program and just select them on GUI to run a new photochemical model. Graphical Abstract
{"title":"Photochemical and radiation transport model for extensive use (PROTEUS)","authors":"Yuki Nakamura, Naoki Terada, Shungo Koyama, Tatsuya Yoshida, Hiroki Karyu, Kaori Terada, Takeshi Kuroda, Arihiro Kamada, Isao Murata, Shotaro Sakai, Yuhei Suzuki, Mirai Kobayashi, François Leblanc","doi":"10.1186/s40623-023-01881-w","DOIUrl":"https://doi.org/10.1186/s40623-023-01881-w","url":null,"abstract":"Abstract We introduce a new flexible one-dimensional photochemical model named Photochemical and RadiatiOn Transport model for Extensive USe (PROTEUS), which consists of a Python graphical user interface (GUI) program and Fortran 90 modules. PROTEUS is designed for adaptability to many planetary atmospheres, for flexibility to deal with thousands of or more chemical reactions with high efficiency, and for intuitive operation with GUI. Chemical reactions can be easily implemented into the Python GUI program in a simple string format, and users can intuitively select a planet and chemical reactions on GUI. Chemical reactions selected on GUI are automatically analyzed by string parsing functions in the Python GUI program, then applied to the Fortran 90 modules to simulate with the selected chemical reactions on a selected planet. We performed a benchmark test of PROTEUS to confirm its validity, by applying it to the Martian atmosphere and the Jovian ionosphere. PROTEUS can significantly save the time for those who need to develop a new photochemical model; users just need to write chemical reactions in the Python GUI program and just select them on GUI to run a new photochemical model. Graphical Abstract","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437070","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}
Pub Date : 2023-09-15DOI: 10.1186/s40623-023-01892-7
Cosme Alexandre Oliveira Barros Figueiredo, Rodrigo A. Miranda, Cristiano Max Wrasse, Hisao Takahashi, Diego Barros, Fábio Egito, Geângelo de Matos Rosa, Antonio Hélder Rodrigues Sampaio
Abstract Interaction between Equatorial Plasma Bubbles (EPBs) and midnight Brightness wave (MBW) was observed over Bom Jesus da Lapa (13.3° S, 43.5° W; Quasi-Dipole geomagnetic latitude of 14.1° S), using OI 630 nm all-sky images. On the night of December 22nd, 2019, an EPB was seen propagating eastward in its fossil stage until it interacted with an MBW. After the interaction, the west walls of EPBs generated secondary instabilities that can be associated with gradient drift instability (GDI) and/or Kelvin–Helmholtz instabilities (KHI). We suggest that the MBW contributed to generate a shear in the EPBs walls due to changes in the thermospheric dynamics, such as neutral wind in the F layer height. Furthermore, spectral analysis of the all-sky images suggests that GDI and/or KHI generated turbulence and helped to dissipate the EPBs. Graphical Abstract
在born Jesus da Lapa(13.3°S, 43.5°W)上空观测了赤道等离子体气泡(EPBs)与午夜亮度波(MBW)的相互作用;准偶极地磁纬度14.1°S)，使用OI 630 nm全天图像。在2019年12月22日晚上，人们看到一只EPB在化石阶段向东传播，直到它与MBW相互作用。相互作用后，epb的西壁产生了与梯度漂移不稳定性(GDI)和/或开尔文-亥姆霍兹不稳定性(KHI)相关的二次不稳定性。我们认为，由于热层动力学的变化，例如F层高度的中性风，MBW有助于在epb壁上产生切变。此外，对全天图像的光谱分析表明，GDI和/或KHI产生了湍流，并有助于消散epb。图形抽象
{"title":"Secondary instability generated on the equatorial plasma bubbles wall due to an interaction with midnight brightness wave","authors":"Cosme Alexandre Oliveira Barros Figueiredo, Rodrigo A. Miranda, Cristiano Max Wrasse, Hisao Takahashi, Diego Barros, Fábio Egito, Geângelo de Matos Rosa, Antonio Hélder Rodrigues Sampaio","doi":"10.1186/s40623-023-01892-7","DOIUrl":"https://doi.org/10.1186/s40623-023-01892-7","url":null,"abstract":"Abstract Interaction between Equatorial Plasma Bubbles (EPBs) and midnight Brightness wave (MBW) was observed over Bom Jesus da Lapa (13.3° S, 43.5° W; Quasi-Dipole geomagnetic latitude of 14.1° S), using OI 630 nm all-sky images. On the night of December 22nd, 2019, an EPB was seen propagating eastward in its fossil stage until it interacted with an MBW. After the interaction, the west walls of EPBs generated secondary instabilities that can be associated with gradient drift instability (GDI) and/or Kelvin–Helmholtz instabilities (KHI). We suggest that the MBW contributed to generate a shear in the EPBs walls due to changes in the thermospheric dynamics, such as neutral wind in the F layer height. Furthermore, spectral analysis of the all-sky images suggests that GDI and/or KHI generated turbulence and helped to dissipate the EPBs. Graphical Abstract","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"212 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135437076","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}
Pub Date : 2023-09-14DOI: 10.1186/s40623-023-01896-3
Ryuho Kataoka, Shinya Nakano, Shigeru Fujita
Abstract Physics-based simulations are important for elucidating the fundamental mechanisms behind the time-varying complex ionospheric conditions, such as ionospheric potential, against unprecedented solar wind variations incident on the Earth’s magnetosphere. However, carrying out an extensive parameter survey for comprehending the nonlinear solar wind density dependence of the ionospheric potential, for example, requires state-of-the-art global magnetohydrodynamic (MHD) simulations, which cannot be executed efficiently even on large-scale cluster computers. Here, we report the performance of a machine-learning based surrogate model for estimating the ionospheric potential outputs of a global MHD simulation, using the reservoir computing technique called echo state network (ESN). The trained ESN-based emulator demonstrates exceptional speed in conducting the parameter survey, which can lead to the identification of a solar wind density dependence of the ionospheric polar cap potential. Finally, we discuss future directions including the promising application for space weather forecasting. Graphical Abstract
{"title":"Machine learning emulator for physics-based prediction of ionospheric potential response to solar wind variations","authors":"Ryuho Kataoka, Shinya Nakano, Shigeru Fujita","doi":"10.1186/s40623-023-01896-3","DOIUrl":"https://doi.org/10.1186/s40623-023-01896-3","url":null,"abstract":"Abstract Physics-based simulations are important for elucidating the fundamental mechanisms behind the time-varying complex ionospheric conditions, such as ionospheric potential, against unprecedented solar wind variations incident on the Earth’s magnetosphere. However, carrying out an extensive parameter survey for comprehending the nonlinear solar wind density dependence of the ionospheric potential, for example, requires state-of-the-art global magnetohydrodynamic (MHD) simulations, which cannot be executed efficiently even on large-scale cluster computers. Here, we report the performance of a machine-learning based surrogate model for estimating the ionospheric potential outputs of a global MHD simulation, using the reservoir computing technique called echo state network (ESN). The trained ESN-based emulator demonstrates exceptional speed in conducting the parameter survey, which can lead to the identification of a solar wind density dependence of the ionospheric polar cap potential. Finally, we discuss future directions including the promising application for space weather forecasting. Graphical Abstract","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134912204","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}
Pub Date : 2023-09-13DOI: 10.1186/s40623-023-01897-2
Po-Han Lee, Jann-Yenq Liu
Abstract Continuous observations at specified locations and chronicling of astronomical phenomena provide a good opportunity to study ancient space weather. There are 248 white, 125 red, and 44 blue color aurora-like descriptions, also known as aurora candidates, recorded in Chinese official historical records during the 1365-year period of 511–1876. Qualitative descriptions of the color, location, and appearance time of these candidates are quantitatively denoted. The red, white, and blue aurora candidates occurred most frequently 34% in autumn, 32% in summer, and 49% in summer, respectively. The white and red aurora as well as the overall candidates tend to appear during high solar activity periods. By contrast, the blue candidates frequently occur during low solar activity periods. Statistical results with 90% confidence intervals further show that the relationship between solar activities and overall/red (white/blue) aurora candidates is significant (insignificant). The red aurora candidates that frequently occurred in autumn during the periods of high solar activity agree well with those of low/middle latitude auroras, while the white aurora candidates might be confounded by noctilucent clouds or other atmospheric optical events, such as airglows, moon halo, etc. The study of ancient space weather/climate based on historical records shows that aurora occurrences are related to solar activities, and in particular, red auroras frequently appear in low/middle latitudes during high solar activity periods. Graphical Abstract
{"title":"Response of aurora candidates in the Chinese official histories to the space climate during 511–1876","authors":"Po-Han Lee, Jann-Yenq Liu","doi":"10.1186/s40623-023-01897-2","DOIUrl":"https://doi.org/10.1186/s40623-023-01897-2","url":null,"abstract":"Abstract Continuous observations at specified locations and chronicling of astronomical phenomena provide a good opportunity to study ancient space weather. There are 248 white, 125 red, and 44 blue color aurora-like descriptions, also known as aurora candidates, recorded in Chinese official historical records during the 1365-year period of 511–1876. Qualitative descriptions of the color, location, and appearance time of these candidates are quantitatively denoted. The red, white, and blue aurora candidates occurred most frequently 34% in autumn, 32% in summer, and 49% in summer, respectively. The white and red aurora as well as the overall candidates tend to appear during high solar activity periods. By contrast, the blue candidates frequently occur during low solar activity periods. Statistical results with 90% confidence intervals further show that the relationship between solar activities and overall/red (white/blue) aurora candidates is significant (insignificant). The red aurora candidates that frequently occurred in autumn during the periods of high solar activity agree well with those of low/middle latitude auroras, while the white aurora candidates might be confounded by noctilucent clouds or other atmospheric optical events, such as airglows, moon halo, etc. The study of ancient space weather/climate based on historical records shows that aurora occurrences are related to solar activities, and in particular, red auroras frequently appear in low/middle latitudes during high solar activity periods. Graphical Abstract","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135741578","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}
Pub Date : 2023-09-12DOI: 10.1186/s40623-023-01893-6
C. Stolle, J. Baerenzung, E. A. Kronberg, J. Kusche, H. Liu, H. Shimizu
{"title":"Special issue “DynamicEarth: Earth’s interior, surface, ocean, atmosphere, and near space interactions”","authors":"C. Stolle, J. Baerenzung, E. A. Kronberg, J. Kusche, H. Liu, H. Shimizu","doi":"10.1186/s40623-023-01893-6","DOIUrl":"https://doi.org/10.1186/s40623-023-01893-6","url":null,"abstract":"","PeriodicalId":11409,"journal":{"name":"Earth, Planets and Space","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135878054","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}
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