To define a background in the electromagnetic emissions above seismic regions, it is necessary to define the statistical distribution of the wave energy in absence of seismic activity and any other anomalous input (e.g. solar forcing). This paper presents a completely new method to determine both the environmental and instrumental background applied to the entire DEMETER satellite electric and magnetic field data over L’Aquila. Our technique is based on a new data analysis tool called ALIF (Adaptive Local Iterative Filtering, [Cicone et al., 2016 and 2017; Piersanti et al., 2017]). To evaluate the instrumental noise, we performed a multiscale statistical analysis, in which the instantaneous relative energy (ϵ rel ), kurtosis and Shannon entropy was calculated. To estimate the environmental noise, a background map, divided into 1° × 1° latitude/longitude cells, of the averaged relative energy ( ϵ rel ) has been constructed, taking into account the geomagnetic activity conditions, the presence of seismic activity and the local time sector of the satellite orbit. Any distinct signal different (over a certain threshold) from both the instrumental and environmental backgrounds will be considered as a case event to be investigated. Interestingly, on April 4, 2009, when DEMETER flew exactly over L’Aquila at UT = 20:29, an anomalous signal was observed at 333 Hz on both the electric and magnetic field data, whose characteristics seem to be related to pre-seismic activity.