Acoustic techniques in ocean information and communication for sustainability

Passive Acoustic Monitoring (PAM) provides a key ocean environmental monitoring approach as it enables estimation of parameters such as wind, rain, ocean water column depth, sea bed and sub bottom classification, using the prevailing ambient sound in the ocean, thereby protecting the marine ecosystem. PAM helps to determine Underwater Radiated Noise (URN) from ships and other human made noises, in order to reduce anthropogenic noise so that no harm is caused to marine life and their habitats. The Autonomous Passive Acoustic Monitoring system developed by National Institute of Ocean Technology (NIOT) plays a key role in tackling ecological issues based on acoustic data from the sea, and supporting sustainability across the blue economy. The PAM system of NIOT has been operational in the Indian seas since 2011 and the Arctic since 2015. NIOT has advanced this Ambient Noise Measurement System (ANMS) over the years to enhance data acquisition, storage, and processing; thereby extending PAM to a developmentally important tool for long term monitoring to promote ocean sustainability. The primary goal of the PAM by NIOT is to acquire ambient sound in the oceans for geo-acoustic, bioacoustic and acoustical oceanographic applications. With PAM, the blue economy can address ecological challenges to monitor marine biodiversity, assess the health of theecosystem, and assess human impacts to oceans. PAM provides a multi-scalar study of the ecosystems- from organisms and species to populations and communities, and soundscapes to measure biological (biophony), geophysical (geophony), and anthropogenic (anthrophony) sounds at any one time, and in any place.