Journal of atmospheric electricity最新文献

{"title":"Relationship between Growing Speed and Turret Development","authors":"F. Kobayashi, Akihito Katsura, Takumi Ookubo","doi":"10.1541/jae.38.1","DOIUrl":"https://doi.org/10.1541/jae.38.1","url":null,"abstract":"On the basis of conducting simultaneous observations of cumulonimbi using the X-band radar, and photogrammetry, several cases of cumulonimbus initiations were observed during the mid-summer days from 2010 to 2011 in the southern Kanto region of Japan. The relationship between the maximum growing speed and the maximum height of 40 turrets was almost linear. The average maximum growing speed was 7 m/s. Turrets were categorized into two groups based on their growing speed, relative to this value. The first, named the “inactive” group, consists of turrets that have a relatively low growing speed with a maximum growing speed that is less than 8.5 m/s, and reach up to 8 km AGL. Another group is the “active” group, in which the turrets develop vertically (10 km or more AGL) with a larger maximum growing speed (> 8.5 m/s). In the active group, some turrets grew with a maximum growing speed that was greater than 15 m/s and had a maximum height that was recorded as greater than 10 or 15 km AGL. The turrets that developed over the Boso Peninsula, Japan, during the observation period indicated that the generation area moved northward as time progressed and turrets eventually developed in the northern regions of the Boso Peninsula.","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"149 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123318296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On a two dimensional simulation model of lightning stepped leader considering its fractalcharacteristics","authors":"Yutaka Konishi, T. Takeuti, Shou Inoue, T. Hashimoto, N. Takagi, Y. Katsuragi","doi":"10.1541/JAE.16.29","DOIUrl":"https://doi.org/10.1541/JAE.16.29","url":null,"abstract":"","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"272 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123418247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of geomagnetic storms on VLF waves at low latitudes based on the analysis of whistlers and VLF emissions observed at Indian ground stations: A Review","authors":"K. K. Singh, A. P. Mishra","doi":"10.1541/jae.38.67","DOIUrl":"https://doi.org/10.1541/jae.38.67","url":null,"abstract":". A review of the effect of geomagnetic storms on very low frequency (VLF) waves (whistlers and emissions) at low latitudes is presented, based on the spectral analysis of the storm-time VLF data collected over a period of about four decades at our low latitude ground-based Indian stations. The review begins with an introduction about the characteristics of whistlers and VLF emissions and the importance of storm-time VLF events for the developments of our theoretical knowledge in plasma physics. This is followed by four different sections (2-5) in order to understand and explain the physics of VLF events observed at low latitudes during magnetic storms. All aspects of whistler duct and geomagnetic activity are described in section 2 whereas section 3 deals with VLF wave (whistlers and emissions) activity and whistler dispersion. Section 4 presents method of analysis of whistler duct alongwith duct lifetime and VLF emission source used in the spectral analysis of storm-time VLF data reported in the present paper. Section 5 describes in brief the experimental setup used in recording of VLF data at our Indian ground stations with a presentation of some selected storm-time whistlers and emissions alongwith their detailed spectral analysis of the observed salient features. Spectral analyses of the storm-time whistlers and emissions using VLF data from our Indian stations have provided the following results (section 6): mid/high latitude emissions generated in the equatorial region of higher 𝐿 -values through the process of Doppler-shifted cyclotron resonance mechanism and propagated along the higher field lines in different ducts formed by disturbances during magnetic storm and after exiting from the ducts, they penetrated the ionosphere and are trapped in Earth-ionosphere waveguide and after propagating in the waveguide are thus recorded at low latitude ground stations. (3) The increased intensity of whistler and emission activities during magnetic storm periods are due to the formation of additional ducts by the enhanced flux of energetic electrons during magnetic storm periods. along with their dispersion analysis. The dispersion analysis of the storm-time whistlers observed at mentioned Indian stations, shows, that unusual high dispersion whistlers are registered during magnetic storm periods and their dispersions ranges from about 15 - 250 s 1/2 . From the dispersion analysis of these observed storm-time high dispersion whistlers using Dowder-Allcock method (Dowden and Allcock, 1971) and curve-fitting technique of Tarcsai (Tarcsai, 1975), we find that these whistlers have propagated along the higher geomagnetic field lines in different ducts corresponding to 𝐿 -values of 2.88 to 6.52. Hence it may be inferred that storm-time whistlers recorded at low latitudes belong to mid/high latitudes and these whistlers may have propagated in different ducts along higher 𝐿 -values and after exiting from ducts, they penetrated the ionosphere and are trappe","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122951589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Statistical relation among earthquakes, average wind speed on the earth's surface, and anomalous propagation of broadcasting waves in the line-of-sight VHF band","authors":"K. Tanigawa, K. Motojima, N. Haga","doi":"10.1541/JAE.37.11","DOIUrl":"https://doi.org/10.1541/JAE.37.11","url":null,"abstract":"This paper was intended to find out any relation between anomalous lineof-sight propagation on the very high frequency (VHF) band and occurrences of earthquakes near the VHF propagation paths. After the stochastic consideration, it was found out that earthquakes associated with anomalous propagation were characterized by relatively large magnitude earthquakes, and relatively near distances from epicenters. Moreover, the authors investigated the relation between average wind speed on the earth’s surface and anomalous line-of-sight propagation in VHF band. As a result, we can obtain the high probability which indicates strong relation between the anomalous propagation and occurrences of earthquakes by considering the average wind speed of the earth’s surface.","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125230336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Frequency and seasonal variation of single lightning flash storm, ″Ippatsurai″, in Japan","authors":"S. Hayashi, Chizuru Marui","doi":"10.1541/JAE.36.13","DOIUrl":"https://doi.org/10.1541/JAE.36.13","url":null,"abstract":"It is well known that single lightning flash storm (SLFS, Ippatsurai in Japanese) is sometimes observed Hokuriku area in winter Japan. However, the frequency and seasonal variation of SLFS are not evaluated quantitatively over the whole of Japan. We investigate the variability of SLFS by using human observations at weather station and electromagnetic observations over Japan from December 2009 to November 2011 for 3 years by Japan Meteorological Agency. As a result, it is confirmed that the higher occurrences of SLFS are concentrated on the Hokuriku coastal area in winter. Additionally, SLFS is also highly observed in Kuroshio extension region in winter and with scattered distribution over the western Japan in summer.","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126153344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphology of winter sprites in the Hokuriku area of Japan : Monthly variation and dependence on air temperature","authors":"K. Myokei, Y. Matsudo, T. Asano, M. Sekiguchi, Tomoyuki Suzuki, Y. Hobara, M. Hayakawa","doi":"10.1541/JAE.29.23","DOIUrl":"https://doi.org/10.1541/JAE.29.23","url":null,"abstract":"Continuous observations of mesospheric optical emissions (sprites) were performed from two optical sites, Shimizu and Chofu during the period of seven months from November 2004 to May 2005, with the target of specific winter sprites in the Hokuriku area of Japan (in the coast of Japan Sea). Two different kinds of analysis have been performed; one is based on the monthly data and the second is the case study. The correlation between the monthly percentage occurrence of different sprite types (columns, carrots and intermediate (including V-shaped sprites, co-existence of columns and carrots)) and monthly variation of the –10oC temperature height has indicated a negative value (r ∼ –0.41) for columns and a high positive value (r ∼ +0.69) for carrots. Further detailed analysis was performed with the height of –10°C at the time of sprite occurrence. It was found that winter sprites occur when the height of –10°C isotherm is located in a range from 1200 m to 3000 m. When the altitude is small, like 1200 – 1400 m, the dominant shape is columnar. When the height of –10°C is increased up to 1800 – 3000 m, a new situation takes place; that is, more spectacular shapes like carrots tend to be frequently observed. This point is also confirmed by analyzing the temperature at a particular height of 850 hPa. Carrots tend to occur above a threshold of temperature of 850 hPa (–7°C). We can conclude that charge height as the consequence charge separation caused by vertical temperature variation plays an essential role in determining the spatial forms of sprites. Finally, we discuss the initiation of sprites and sprite morphology, with a reference to the observed facts in this paper.","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129274300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An evidence on the lithosphere-ionosphere coupling in terms of atmospheric gravity waves on the basis of a combined analysis of surface pressure, ionospheric perturbations and ground-based ULF variations","authors":"T. Nakamura, V. Korepanov, Y. Kasahara, Y. Hobara, M. Hayakawa","doi":"10.1541/JAE.33.53","DOIUrl":"https://doi.org/10.1541/JAE.33.53","url":null,"abstract":"One major candidate of lithosphere-atmosphere-ionosphere (LAI) coupling mechanism is through atmospheric oscillations triggered near Earth’s surface due to some pre-earthquake (EQ) effect, and this channel has been extensively proved by using meteorological disturbances much more easily treated than pre-EQ effects (Korepanov et al., 2009). In the present paper this channel is challengingly studied, for the first time, for pre-EQ phenomena, and we take a rather strong EQ named Niigata-chuetsu EQ on 23 October, 2004 (with magnitude of 6.8 and with depth of 13 km) for which we already know that the ionospheric perturbation did take place prior to the EQ (Hayakawa et al., 2006). In this paper the LAI coupling has been intensively studied by means of coordinated observational data (surface atmospheric pressure data as an indicator of atmospheric gravity waves (AGWs), our own subionospheric VLF/LF data as a measure of ionospheric perturbations and the ground-based ULF data as a measure to monitor the modulation in the ionospheric dynamic region). The wavelet analyses for these parameters in different spatial regions have all indicated the enhancements of fluctuations in the wave frequency of 10 ~ 100 min (in the frequency range of AGWs). The correlation of wavelet spectra between the atmospheric pressure and VLF/LF amplitude has yielded a high value with the delay of a few hours, while there is nearly no distinct delay of the wavelet spectra between the ionospheric perturbation and the ground-based ULF fluctuation. These observational facts are compared with the theoretical estimation of AGW hypothesis, which may provide a convincing support to the AGW channel of the LAI coupling.","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"173 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133851291","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Statistical relation between lightning and anomalous propagation in the line-of-sight VHF band","authors":"Toshitaka Nanjo, N. Haga, K. Motojima, H. Iwasaki","doi":"10.1541/JAE.36.23","DOIUrl":"https://doi.org/10.1541/JAE.36.23","url":null,"abstract":". In order to make a prediction of earthquakes, we have to find out any relationship between electromagnetic phenomena and earthquakes. We have been observed VHF radio waves that propagate from line-of-sight region for several years. During the observation, we noticed some anomalous propagation associated with lightning storms on the VHF band. When strong lightning storms occur, the anomalous propagation sometimes appears on the VHF radio waves. To get more absolute relationship between anomalous propagation and earthquakes, the anomaly associated without earthquakes should be excluded from anomaly data. Therefore, we investigate the relationship between the anomalous propagation on VHF radio waves and occurrences of lightning storms by statistical original method. In this paper, using statistical estimation, we find out strong relationship between the anomalous propagation on the VHF band and occurrences of lightning storms near the wave propagation path.","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"289 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122693539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fine progression features of return stroke luminosity at the bottom of rocket-triggered lightning channels","authors":"Haitao Huang, Daohong Wang, M. Uman, Ting Wu, N. Takagi","doi":"10.1541/JAE.39.57","DOIUrl":"https://doi.org/10.1541/JAE.39.57","url":null,"abstract":"We have performed a study on the luminosity waveforms of 13 return strokes (RSs) in 4 rocket triggered lightning flashes recorded by a high-speed optical imaging system LAPOS5 with a time resolution of 35 ns and a spatial resolution of about 2 m. It was found that as the return strokes propagate upward over the bottom 10 m to 26 m of the lightning channels, which is above their initiation heights, on average the RSs optical waveforms decrease their peaks by 41%, lengthen their 20-90% rise times and 100-80% decay times, and change the relative times of the fastest rising points by 0.38 μs, 0.51 μs, and 0.15 μs. We have also estimated the propagation speeds for all the return strokes by using their 20% peak light intensity points and fastest rising points as reference points for time difference measurements, respectively. It was found that the average RS speed obtained with the 20% peak light intensity points (1.11× 108 m/s) is about twice that obtained with the fastest rising points (0.67× 108 m/s). In addition, we found that for different RSs in an individual lightning flash, the RS with faster propagation speed tends to have a less distorted optical waveform at the higher height.","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128462569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observation results of non-line-of sight 77.1 MHz FM radio waves on three different paths for three years","authors":"M. Nishi, Hidemitsu Shinbara, K. Shin, Teruaki Yoshida","doi":"10.1541/JAE.31.11","DOIUrl":"https://doi.org/10.1541/JAE.31.11","url":null,"abstract":"","PeriodicalId":274637,"journal":{"name":"Journal of atmospheric electricity","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127176489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}