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Abstract Previous studies have shown that subsequent leaders in positive cloud‐to‐ground lightning (+CG) flashes rarely traverse pre‐existing channels to ground. In this paper, we present evidence that this actually can be common, at least for some thunderstorms. Observations of +CG flashes in a supercell storm in Argentina by Córdoba Argentina Marx Meter Array (CAMMA) are presented, in which 54 (64%) of 84 multiple‐stroke +CG flashes had subsequent leaders following a pre‐existing channel to ground. These subsequent positive leaders are found to behave similarly to their negative counterparts, including propagation speeds along pre‐existing channels with a median of 8 × 106 m/s, which is comparable to that of negative dart leaders. Two representative multiple‐stroke +CG flashes are presented and discussed in detail. The observations reported herein call for an update to the traditional explanation of the disparity between positive and negative lightning.
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Huntsville Alabama Marx Meter Array 2: Upgrade and Capability
Abstract The Córdoba Argentina Marx Meter Array (CAMMA), consisting of 10 second‐generation Huntsville Alabama Marx Meter Array (HAMMA 2) sensors, operated at Córdoba, Argentina, during the Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaign in late 2018. Initial results obtained from the campaign demonstrate that the new sensor is able to provide a significantly more detailed depiction of various lightning processes than its first generation. The lightning flashes mapped by the CAMMA and a colocated Lightning Mapping Array (LMA) were compared. The overall flash structures mapped by the CAMMA and the LMA look similar for most of the flashes. However, comparisons at smaller time scale show that the majority of CAMMA and LMA sources are not concurrent, indicating that unmatched sources were possibly due to different physical processes in leader propagation dominating different frequencies and differences in data processing and location techniques.
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- PAR ID:
- 10448826
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Earth and Space Science
- Volume:
- 7
- Issue:
- 4
- ISSN:
- 2333-5084
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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