An overview of the lightning and atmospheric electricity observations collected in southern France during the HYdrological cycle in Mediterranean EXperiment (HyMeX), Special Observation Period 1

Abstract

Abstract. The PEACH project (Projet en Electricité Atmosphérique pour la Campagne HyMeX -the Atmospheric Electricity Project of the HyMeX Program) is the atmospheric electricity component of the Hydrology cycle in the Mediterranean Experiment (HyMeX) experiment and is dedicated to the observation of both lightning activity and electrical state of continental and maritime thunderstorms in the area of the Mediterranean Sea. During the HyMeX SOP1 (Special Observation Period) from 5 September to 6 November 2012, four European operational lightning locating systems (ATDnet, EUCLID, LINET, ZEUS) and the HyMeX lightning mapping array network (HyLMA) were used to locate and characterize the lightning activity over the northwestern Mediterranean at flash, storm and regional scales. Additional research instruments like slow antennas, video cameras, microbarometer and microphone arrays were also operated. All these observations in conjunction with operational/research ground-based and airborne radars, rain gauges and in situ microphysical records are aimed at characterizing and understanding electrically active and highly precipitating events over southeastern France that often lead to severe flash floods. Simulations performed with cloud resolving models like Meso-NH and Weather Research and Forecasting are used to interpret the results and to investigate further the links between dynamics, microphysics, electrification and lightning occurrence. Herein we present an overview of the PEACH project and its different instruments. Examples are discussed to illustrate the comprehensive and Published by Copernicus Publications on behalf of the European Geosciences Union. E. Defer et al.: Atmospheric electricity observations during HyMeX SOP1unique lightning data set, from radio frequency to acoustics, collected during the SOP1 for lightning phenomenology understanding, instrumentation validation, storm characterization and modeling.

The European lightning location system EUCLID – Part 2: Observations

“…This improvement is attributed to an increased number of sensors contributing to the network, but is also due to the upgrade of the older type of sensors into the newest LS700x sensor technology and by the implementation of advanced processing algorithms (Schulz et al, 2015). Nevertheless, for the purpose of this study it can be assumed that from 2006 onward the improvements to the network in terms of flash detection efficiency and location accuracy will have minimal influence on the outcome presented in the remainder of this paper.…”

“…As such, it is possible to retrieve not only the geographical and frequency distribution of lightning on a global scale (Jacobson et al, 2006;Keogh et al, 2006;Said et al, 2010Said et al, , 2013, but detailed information at the level of individual strokes or flashes as well by means of three-dimensional reconstruction of the development of the lightning channel as observed by present-day lightning mapping arrays (LMAs) (Rison et al, 1999;Thomas et al, 2004;van der Velde et al, 2013;Defer et al, 2015). Nevertheless, each LLS has its pros and cons.…”

“…The performance of EUCLID has been frequently tested over the years in terms of its location accuracy, detection efficiency and peak current estimation. For the latest in-depth analysis of the performance validation of EU-CLID in Europe, the interested reader is referred to Schulz et al (2015). A description of the treatment of the data and methodology is provided in Sect.…”

The European lightning location system EUCLID – Part 1: Performance analysis and validation

“…3c) -In 2012, during the HyMeX project (Ducrocy et al, 2013;Defer et al, 2015) ground truth data were collected with the VFRS in southern France and in 2013 a separate measurement campaign was organized in the north of France.…”

“…Further data from a VHF mapping system (Lightning Mapping Array) were used during the HyMeX experiment (Ducrocy et al, 2013;Defer et al, 2015) in the south of France to validate the EUCLID DE of intra-cloud discharges (Schulz et al, 2014b;Pédeboy et al, 2014).…”