This contribution aims to assess the sensitivity of the time domain response of a straight thin electrode buried in a lossy half-space. The issue is of crucial importance in many fields including electrical engineering (e.g. ground penetrating radar purposes, lightning protection for electrical settlements). Indeed, such systems are subject to more and more complex radiating coupling, mostly due to the variability of input parameters. An alternative approach to classical Sobol’ indices is proposed here, jointly with an analytical resolution of Pocklington integro-differential equation.