Event detection of underwater acoustic data from MACHO hydrophone

Abstract

This paper presents an automated event detector of long time series of hydrophone data from Marine Cable Hosted Observatory (MACHO) system installed by the Central Weather Bureau in the offshore region of Taiwan's northeast coast. The detector includes time-varying ambient noise level estimation via SEL (Sound Exposure Level per second) and Leq (equivalent continuous sound level, averaged over 30 seconds), and an energy detector with the estimated ambient noise level as threshold. A user friendly UI (user interface) is written to enhance the utilization. A full year of data are analyzed with the detector, and the results are satisfactory in the robustness the detection rate and the efficiency of analysis of large amount of data.