Speaker
Description
The incorporation of the hydroacoustic station HA04, Crozet Islands, France, into the International Monitoring System (IMS) of the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO) was successfully completed on 29 December 2016. HA04 was Certified and Promoted into Operations on 19 June 2017. Similarly to most other cabled hydroacoustic stations in the IMS, HA04 is comprised of two triplets of moored hydrophones deployed on both sides of Possession Island (Crozet Islands) sending uninterrupted data to a shore facility via submarine fiber optic cables. The designed frequency pass-band is 1 – 100 Hz. Data are relayed to Vienna via a shore based satellite link in real time. According to CTBTO’s standard requirements, the design life of HA04 is at least 20 years, maintenance-free for the underwater system. An outline of the main phases of this project, highlights from the installation operations and examples of received hydroacoustic signals associated with underwater seismic activity in the Indian Ocean as well as vocalizations from marine mammals acquired by the new HA04 are presented here. The integration of HA04 into the operational platform of IDC will enable registered researchers to access archived monitoring data and processing software, or via the National Data Centres (NDCs).
