Energetic Intra-Cloud Lightning in the RELAMPAGO Field Campaign
Journal Article
Overview
abstract
A particular strength of lightning remote sensing is the variety of; lightning types observed, each with a unique occurrence context and; characteristically different emission. Distinct energetic intra-cloud; (EIC) lightning discharges – compact intra-cloud lightning discharges; (CIDs) and energetic intra-cloud pulses (EIPs) – produce intense RF; radiation, suggesting large currents inside the cloud, and they also; have different production mechanisms and occurrence contexts. A; Low-Frequency (LF) lightning remote sensing instrument array was; deployed during the RELAMPAGO field campaign in west central Argentina,; designed to investigate convective storms that produce high-impact; weather. LF data from the campaign can provide a valuable dataset for; researching the lightning context of EICs in a variety of sub-tropical; convective storms. This paper describes the production of an LF-CID; dataset in RELAMPAGO, and includes a preliminary analysis of CID; prevalence.; Geolocated lightning events and their; corresponding observed waveforms from the RELAMPAGO LF dataset are used; in the classification of EICs. Height estimates based on skywave; reflections are computed, where pre-fit residual data editing is used to; improve robustness against outliers. Even if EIPs occurred within the; network, given the low number of very high peak current events and; receiver saturation, automatic classification of EIPs may not be; feasible using this dataset. The classification of CIDs, on the other; hand, is straightforward and their properties, for both positive and; negative polarity, are investigated. A few RELAMPAGO case studies are; also presented, where high variability of CID prevalence in ordinary; storms and high-altitude positive CIDs, possibly in overshooting tops,; are observed.
