Project Deliverable D50 Report on Best Practices ... - ESONET NoE

In the marine environment a diversity of sounds is typically found. Physical processes, marine
organisms and human activities generally contribute to produce these sound sources.
This constitutes a challenging environment for automated classifiers because (1) the target
sources are often embedded in background noise (2) non-target sources can cause false
detections or conversely attenuate the detection of the target sources. There is a need of
developing a system for the detection of many acoustic events relevant to the monitoring and
study of the interactions between cetaceans and anthropogenic sounds. The system is to be
used for the long-term data (several months or years) assessment. It should tag segments that
contain acoustic events of a particular class, allowing for example (1) mitigation actions to be
undertaken, (2) to obtain long time series of the occurrence of a particular sound, (3) to avoid
the unnecessary storage or transmission of data that contains none of the events of interest.
The output of the Demonstration Mission LIDO is providing such a system in the form of a
modular architecture that is ensuring the real-time process of the data. The challenge is here to
be able to find a reliable set of filters or detectors able to extract the interesting information
that would be superimposed to background-noise, like dolphin calls and sonar, sperm and
beaked whale clicks, or noise produced by ship engine.
A schematic overview of the classification system is described in the following text. The
audio data stream is processed by segments of 22 seconds. The output of the system takes the
form of tags, which are appended to a segment if the corresponding acoustic event is detected.
The first stage of the system detects broad classes of events. The second stage classifies
segments into more specific classes. The system’s modules can be run independently, thereby
allowing to implement smaller and faster versions, aimed at specific classes of sounds or
mitigation scenarios, like the detection and tracking of specific whale species, the presence of
ships or other human activities. New modules can be incorporated into the system.
The system is being specifically designed to be adapted to different scenarios, shallow vs.
deep waters, different background noise, different human activities, different marine mammal
species, etc., following standard procedures in compliance with the GEOSS guidelines for
interoperability, the standard sensor registration and discoverability of acoustic sensors.
4.3 Infrastructure
4.3.1 Design comparison – Cabled observatories
4.3.1.1 Introductory text
Several subsea cabled observatories are operated or under final construction. Some elements
were presented during the First Best Practice Workshop in Bremen. This panel will update
this information.
The cost evaluation performed by ESONET WP5 group will be reviewed and compared with
standalone solutions. The panel will look more carefully at one case, taking into account the
scientific objectives presented earlier in the week at the All Regions Workshop 2 in Paris.
System engineering issues for the various components of the infrastructure will be addressed.
For the remaining integration budget in ESONET, the Steering Committee decided to open a
call for the partners. The main objective of the call is to promote test of equipment and
instruments on cabled subsea observatory sites. The results of the two Demonstration Mission
Calls of ESONET showed a lack in the field of cabled observatories experiment.
A unified proposal for test on cabled sites is under final acceptance process. It will be
presented to the panel for discussion and suggestion according to the practices of the
<strong>Deliverable</strong> #50 - update October 2010 11