Multilinear approach to the precipitation–lightning relationship: a case study of summer local electrical storms in the northern part of Spain during 2002–2009 period
I. Herrero1, A. Ezcurra2, J. Areitio3, J. Diaz-Argandoña4, G. Ibarra-Berastegi5, and J. Saenz61Dpto. Expresión Gráfica y Proyectos, Universidad del País Vasco UPV-EHU, Escuela Universitaria de Ingeniería Técnica Industrial, 48013-Bilbao, Spain 2Dpto. Física Aplicada II, Universidad del País Vasco UPV-EHU, Facultad de Farmacia, 01006-Vitoria, Spain 3Research staff of the Meteorological Association of the Basque Country, Amillena, Vitoria, Spain 4Dpto. Física Aplicada I, Universidad del País Vasco UPV-EHU, Escuela Universitaria de Ingeniería Técnica Industrial, 01006-Vitoria, Spain 5Dpto. Ingenieria Nuclear y Mecánica de Fluídos, Escuela Técnica Superior de Ingeniería, 48013-Bilbao, Spain 6Dpto. Física Aplicada II, Universidad del País Vasco UPV-EHU, Apdo. 644, 4808-Bilbao, Spain
Received: 10 Oct 2013 – Accepted for review: 22 Oct 2013 – Discussion started: 15 Nov 2013
Abstract. Storms developed under local instability conditions are studied in the Spanish Basque region with the aim of establishing precipitation–lightning relationships. Those situations may produce, in some cases, flash flood. Data used correspond to daily rain depth (mm) and the number of CG flashes in the area. Rain and lightning are found to be weakly correlated on a daily basis, a fact that seems related to the existence of opposite gradients in their geographical distribution. Rain anomalies, defined as the difference between observed and estimated rain depth based on CG flashes, are analysed by PCA method. Results show a first EOF explaining 50% of the variability that linearly relates the rain anomalies observed each day and that confirms their spatial structure. Based on those results, a multilinear expression has been developed to estimate the rain accumulated daily in the network based on the CG flashes registered in the area. Moreover, accumulates and maximum values of rain are found to be strongly correlated, therefore making the multilinear expression a useful tool to estimate maximum precipitation during those kind of storms.
Herrero, I., Ezcurra, A., Areitio, J., Diaz-Argandoña, J., Ibarra-Berastegi, G., and Saenz, J.: Multilinear approach to the precipitation–lightning relationship: a case study of summer local electrical storms in the northern part of Spain during 2002–2009 period, Nat. Hazards Earth Syst. Sci. Discuss., 1, 6467-6498, doi:10.5194/nhessd-1-6467-2013, 2013.