A network of deepwater acoustic sensors that provides India’s coastal communities with an early warning of tsunami waves is being upgraded by Sonardyne to extend their endurance and capability.

Deployed at key locations in the Bay of Bengal and the Arabian Sea, the network of Sonardyne’s bottom pressure recorders (BPRs) is owned and operated by India’s National Institute of Ocean Technology (NIOT) as part of the country’s Tsunami Early Warning System (TEWS).

The BPRs were first installed in 2007, as part of NIOT’s national tsunami detection system, which was conceived following the deadly Boxing Day Tsunami of 2004.

The BPRs detect the characteristic changes in water pressure (as little as 1 cm in 4,000-m depth) caused by an earthquake in the deep ocean. If a tsunami wave is detected, an alert message is transmitted up to a satellite buoy on the surface. From there, it is relayed to the national Tsunami Warning Centre onshore for comparison with recent seismic activity. If validated, a wide-scale alarm is raised to alert vulnerable communities.

Following a 10-year life refurbishment in 2017, the BPRs are now being upgraded to Sonardyne’s 6G hardware and Wideband 2 communications standard. The installation of low-power electronics, new lower power consumption pressure sensors and doubled battery capacity of these maxi BPRs will significantly reduce maintenance visits and costs. Additionally, the acoustic telemetry signals used to transmit data to the surface will also now be fully digital, providing greater resilience to noise interference in the water column, as well as increasing bandwidth ten-fold (from 600 to 6,000 bps).

Each BPR is a customized version of Sonardyne’s Compatt transponder, which provides autonomous monitoring and measuring applications for offshore energy, survey and ocean science.

Learn more here.