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, The site is located between 30 and 90 m from the seashore and comprises 16 piezometers. The objective of this paper is to combine different recently developed monitoring techniques to evaluate temporal variations in the aquifer hydrodynamics of the site at different spatial scales before and after the dry season of 2015. At the site scale, fibre optic distributed temperature sensing (FO-DTS), for the first time applied to study SWI, and cross-hole electrical resistivity tomography (CHERT) has been applied, p.39

, but also for the first time at relatively high frequency (1 sample every 10 minutes). understanding of the system by: 1) characterizing the extent and shape of SWI

, 2) differentiating two different dynamics in the aquifer

. Folch, Conceptualization, Methodology, Investigation, Writing -Original Draft, Visualization, Supervision, Project administration, Funding acquisition L. del Val: Conceptualization, Methodology, Investigation, Writing -Review & Editing, Visualization L. Luquot: Conceptualization, Methodology, Investigation, Writing -Review & Editing, Supervision, Project administration, Funding acquisition L. Martínez-Pérez: Conceptualization, Methodology, Investigation, Writing -Review & Editing, Visualization F. Bellmunt: Methodology, Investigation

H. and L. Lay, Methodology, Methodology, Investigation, Writing -Review & Editing V. Rodellas: Methodology, Investigation, Writing -Review & Editing, Visualization N. Ferrer: Investigation A. Palacios: Investigation, Writing -Review & Editing, Visualization S. Fernández: Investigation M. A. Marazuela: Methodology, Investigation

M. Diego, Feliu: Investigation, Writing -Review & Editing, p.40

, M. Pool: Investigation, Writing -Review & Editing T. Goyetche: Investigation, Writing -Review & Editing, Visualization ,J. Ledo: Conceptualization, Methodology, Investigation, Writing -Review & Editing, Supervision, Funding acquisition P. Pezard: Conceptualization, Methodology, Investigation, Writing -Review & Editing O. Bour: Conceptualization, Methodology, Investigation, Writing -Review & Editing P. Queralt: Methodology, Investigation, Writing -Review & Editing A. Marcuello: Methodology, Investigation, Writing -Review & Editing

J. Garcia-orellana, Methodology, Investigation, Writing -Review & Editing, Funding acquisition M.W. Saaltink: Methodology, Investigation, Writing -Review & Editing, Project administration, Funding acquisition E. Vazquez-Suñe: Methodology, Investigation, Funding acquisition J. Carrera: Conceptualization, Investigation, Writing -Review & Editing, Supervision