CTBT: Science and Technology Conference 2025 - SnT2025

Hydroacoustic activities detected in the Indian Ocean during the global outbreak of the COVID-19 pandemic

P5.2-130

Not scheduled

1h

Zeremoniensaal

E-poster T5.2 Regional Empowerment P5.2 Regional Empowerment

Speaker

Andriamiranto Raveloson (Institute and Observatory of Geophysics of Antananarivo (IOGA))

Description

This paper describes the result of hydroacoustic data processing using the Comprehensive Nuclear-Test-Ban Treaty Organization's hydrophones HO1W, HO8S and HO4N during the period between 2018 and 2020 by the National Data Centre (NDC) in Madagascar. The main objective is to apply and follow the recommended steps described by the Provisional Technical Secretariat at the NDC forum website (https://ndc-forum.ctbto.org/t/how-to-process-hydroacoustic-data-in-ndc-in-a-box). We use the PMCC method for data processing with the described detection parameters on the website. During the entire period, detections were continuously observed between azimuth 140 and 250 for HO1W, between azimuth 27 to 35 for HO8S and between azimuth 150 to 200 for HO4N. In addition, we observed signatures of earthquakes along the Indian Ocean Ridge, as well as the Tsunami generated after the Krakatoa volcano eruption on 22 December 2018, ice breaking, and other events. Associating the arrival at the event location is one of the challenges we faced during this study. Consequently, detecting signatures of life below water needs further analysis and experience. We managed to follow and apply the recommended ways to process hydroacoustic data from the International Monitoring System.