Accumulation of pressures that generate underwater noise in the Levantino-Balear Demarcation (EM LEVA PRE Submarine Noise)

The approach to the condition of underwater noise in the Strait and Alboran Demarcation has been made for a mesh of 5x5 minutes, from the sources of continuous noise present in the demarcation, that is, navigation. To this end, a semi-quantitative index has been developed that integrates data from AIS (ships) and VMS (fishers). For the navigation of both merchant vessels and fishing vessels, cells have been selected based on the traffic intensity measured from the density of AIS signals (ships) and VMS (fishers). In both cases, different intensity intervals have been established, each of which has been given a different weight. In addition, the adjoining cells (classified into four ranges) have been selected, giving them different importance depending on proximity. The zero range coincides with the cells in which the signal density is recorded, while the first range corresponds with cells bordering those of the zero range, the second being the cells bordering the first and the third the bordering cells with the second. The end result is the sum of all the weights in each cell, considering exclusively the maximum value for the bordering cells. The values obtained range from 0 to 3.1, with the following classification of levels: Very High: major 2/High: 1.71 to 2/Medium: 0,41 to 1,7/Under: 0.1 to 0,4/Very Low: minor 0.1