| 1. Identity statement | |
| Reference Type | Conference Paper (Conference Proceedings) |
| Site | plutao.sid.inpe.br |
| Holder Code | isadg {BR SPINPE} ibi 8JMKD3MGPCW/3DT298S |
| Identifier | J8LNKAN8RW/3AFLE22 |
| Repository | dpi.inpe.br/plutao/2011/09.22.19.12 (restricted access) |
| Last Update | 2012:01.31.16.21.55 (UTC) secretaria.cpa@dir.inpe.br |
| Metadata Repository | dpi.inpe.br/plutao/2011/09.22.19.12.03 |
| Metadata Last Update | 2018:06.05.00.01.29 (UTC) administrator |
| Label | lattes: 4161737266837399 1 CamposSabaKrid:2011:AMaOf |
| Citation Key | CamposSabaKrid:2011:MaReLe |
| Title | High-speed video observations of β2-type leaders in negative lightning: a manifestation of recoil leaders initiated inside the cloud?  |
| Format | DVD |
| Year | 2011 |
| Access Date | 2024, Apr. 26 |
| Secondary Type | PRE CN |
| Number of Files | 1 |
| Size | 53 KiB |
| 2. Context | |
| Author | 1 Campos, Leandro Zanella de Souza 2 Saba, Marcelo Magalhães Fares 3 Krider, E. Philip |
| Group | 1 DGE-CEA-INPE-MCT-BR 2 CST-CST-INPE-MCT-BR |
| Affiliation | 1 Instituto Nacional de Pesquisas Espaciais (INPE) 2 Instituto Nacional de Pesquisas Espaciais (INPE) 3 Institute of Atmospheric Physics, University of Arizona, Tucson, Arizona, 85721, USA |
| Author e-Mail Address | 1 leandro.zanella@gmail.com |
| e-Mail Address | leandro.zanella@gmail.com |
| Conference Name | International Conference on Atmospheric Electricity, 14. |
| Conference Location | Rio de Janeiro |
| Date | 08-12 Aug |
| Volume | 1 |
| Book Title | Proceedings |
| Tertiary Type | Paper |
| History (UTC) | 2011-09-23 14:11:20 :: lattes -> secretaria.cpa@dir.inpe.br :: 2011 2012-01-31 16:22:07 :: secretaria.cpa@dir.inpe.br -> administrator :: 2011 2018-06-05 00:01:29 :: administrator -> marciana :: 2011 |
| 3. Content and structure | |
| Is the master or a copy? | is the master |
| Content Stage | completed |
| Transferable | 1 |
| Content Type | External Contribution |
| Version Type | publisher |
| Keywords | Atmospheric Electricity Lightning Physics Recoil leaders Lightning Leaders |
| Abstract | ABSTRACT: Schonland et al. (1938), in their seminal streak camera studies of lightning, have identified a peculiar type of negative stepped leader that they termed β, a rather rare variant of the type β leader and in it the second and slower stage of the leader is associated with the appearance of one or more fast dart streamers, which travel rapidly down from the cloud along the previously formed track and cease when they have caught up with the slower leader-tip. They reported four events, two were accompanied by a dart streamer (a nomenclature we will keep for historical reasons), one event contained two examples, and one event that was not described in detail. During a July-August 2007 campaign in Tucson, Arizona, USA, we recorded four downward leaders that fit in the type-β22 description given by Schonland et al. (1938). All cases occurred between about 12 and 32 km from a high-speed camera that was operating at 4000 frames per second. Two cases were produced by the first stroke in a flash, and one case was associated with a subsequent stroke that produced a new ground termination. Our fourth case was a subsequent stroke that began with a dart leader and then changed to a type- stepped leader approximately 1350 m above the ground; in this case, we observed a dart streamer (with the leader tip at about 720 m from the ground) about 3.25 ms after the stepped progression began and the return stroke occurred 2 ms later. All the dart streamers that we observed had speeds between 10 6 and 10 7 m s -1 -2 , in agreement with previous observations of recoil leaders (Saba et al., 2008); therefore, we suggest that the type- negative leaders are the visible manifestation of the development of recoil leaders that were initiated inside the cloud and propagate below the cloud-base, during the development of a bipolar, bidirectional leader that precedes a lightning flash to ground. The recoil leaders develop in previously ionized channels that are produced by the in-cloud 2 positive portion of a bidirectional leader, and when they reach the tip of the negative downward portion, they produce an intense pulse of luminosity that optically appears as a dart streamer. |
| Area | CEA |
| Arrangement 1 | urlib.net > BDMCI > Fonds > Produção anterior à 2021 > DIDGE > High-speed video observations... |
| Arrangement 2 | urlib.net > BDMCI > Fonds > Produção anterior à 2021 > COCST > High-speed video observations... |
| doc Directory Content | access |
| source Directory Content | there are no files |
| agreement Directory Content | there are no files |
| 4. Conditions of access and use | |
| Language | en |
| Target File | LCAMPO-High-speed video observations of 2-type.pdf |
| User Group | lattes secretaria.cpa@dir.inpe.br |
| Visibility | shown |
| Read Permission | deny from all and allow from 150.163 |
| Update Permission | not transferred |
| 5. Allied materials | |
| Next Higher Units | 8JMKD3MGPCW/3EU29DP 8JMKD3MGPCW/3F3T29H |
| Host Collection | dpi.inpe.br/plutao@80/2008/08.19.15.01 |
| 6. Notes | |
| Notes | Informações Adicionais: Schonland et al. (1938), in their seminal streak camera studies of lightning, have identified a peculiar type of negative stepped leader that they termed β 2 , a rather rare variant of the type β leader and in it the second and slower stage of the leader is associated with the appearance of one or more fast dart streamers, which travel rapidly down from the cloud along the previously formed track and cease when they have caught up with the slower leader-tip . They reported four events, two were accompanied by a dart streamer (a nomenclature we will keep for historical reasons), one event contained two examples, and one event that was not described in detail. During a July-August 2007 campaign in Tucson, Arizona, USA, we recorded four downward leaders that fit in the type-β 2 description given by Schonland et al. (1938). All cases occurred between about 12 and 32 km from a high-speed camera that was operating at 4000 frames per second. Two cases were produced by the first stroke in a flash, and one case was associated with a subsequent stroke that produced a new ground termination. Our fourth case was a subsequent stroke that began with a dart leader and then changed to a type-β 2 stepped leader approximately 1350 m above the ground in this case, we observed a dart streamer (with the leader tip at about 720 m from the ground) about 3.25 ms after the stepped progression began and the return stroke occurred 2 ms later. All the dart streamers that we observed had speeds between 10^6 and 10^7 m s^-1, in agreement with previous observations of recoil leaders (Saba et al., 2008) therefore, we suggest that the type-β 2 negative leaders are the visible manifestation of the development of recoil leaders that were initiated inside the cloud and propagate below the cloud-base, during the development of a bipolar, bidirectional leader that precedes a lightning flash to ground. The recoil leaders develop in previously ionized channels that are produced. |
| Empty Fields | archivingpolicy archivist callnumber copyholder copyright creatorhistory descriptionlevel dissemination doi edition editor isbn issn lineage mark mirrorrepository nextedition numberofvolumes orcid organization pages parameterlist parentrepositories previousedition previouslowerunit progress project publisher publisheraddress readergroup resumeid rightsholder schedulinginformation secondarydate secondarykey secondarymark serieseditor session shorttitle sponsor subject tertiarymark type url |
| 7. Description control | |
| e-Mail (login) | marciana |
| update | |