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Scientists from NPL and the Measurement Standards Laboratory (MSL) in New Zealand are set to carry out the first ever optical interferometry-based earthquake sensing tests in the Pacific Ocean. By performing ultra-sensitive optical measurements, scientists from the two laboratories will “convert” a seafloor cable extending offshore New Zealand into an array of sensors for earthquakes and ocean currents. These tests will lay the foundation for investigating the potential use of existing seafloor cables as detectors for tsunami early warning systems.
The technique was first pioneered by NPL in 2021 and derived from techniques used for quantum science. It uses existing optical fibre infrastructure to gather continuous, real-time environmental data from the seabed. NPL previously demonstrated the technique in the Atlantic Ocean on a 5,860km-long intercontinental submarine optical fibre link between the UK and Canada.
The Pacific Ocean is a highly seismically active area, providing an ideal test bed for advancing the technology and demonstrating its full potential. NPL and the MSL will test the technique later this year on a section of the 3,876km-long Southern Cross NEXT cable on the floor of the Tasman Sea between New Zealand and Australia.
More than 70 percent of the Earth’s surface is covered by water, and seas and oceans today are still mainly unmonitored. There are only a handful of permanent ocean-floor sensors in place globally, since installing and maintaining them is challenging and prohibitively expensive. By applying NPL’s technique to a multitude of seafloor cables, thousands of ocean-bottom sensors could be implemented.
NPL’s sensing technique does not require any new hardware or infrastructure to be installed or any changes to existing infrastructure on the seafloor instead, it utilises the optical fibre itself as the environmental sensor. NPL’s technique has the potential to provide a valuable early warning system to safeguard coastal populations in the event of a tsunami. It also offers the first viable solution to fill the gap in data in ocean monitoring, with substantial impact in several scientific areas including seismology and oceanography.
Future projects could develop this concept into a worldwide monitoring network, giving earlier and more accurate detection of earthquakes and tsunamis, as well as advancing the world’s understanding of ocean floor geology and climate change through the long-term monitoring of seafloor temperature changes.
Giuseppe Marra, Principal Scientist, NPL said: “This exciting UK-NZ joint project will enable NPL’s pioneering seafloor cable-based environmental detection technique to be tested in one of the most seismically active regions of the world. This will significantly advance research on these innovative environmental sensing techniques, with impact on a number of science areas, from seismology to oceanography, as well as future societal applications, such as in early tsunami warning systems. This project is a testament to how science is capable of bringing together minds from the world’s antipodes to advance our knowledge of how our planet works and bring positive impact to society.”
Dr Peter Thompson, CEO, NPL, said: “This technology, pioneered at NPL, is the perfect example of how our science can create impact, delivering tangible benefits for society which will simultaneously improve our understanding of the world.”
The project is part of a new collaboration agreement with New Zealand announced on Tuesday 23 April by Andrew Griffith, Minister of State for Science, Research and Innovation, at the Organisation for Economic Co-operation and Development (OECD)’s Committee for Science and Technological Policy Ministerial. UK Science Minister Andrew Griffith said: "Bringing the UK and New Zealand’s brightest minds together, to overhaul how we give advance warning of tsunamis, could save scores of lives. This work proves the value of breakthrough technologies like quantum, as well as the international teamwork that’s crucial to harnessing them.”
Annette Koo, Director and Chief Metrologist, Measurement Standards Laboratory of New Zealand, said: “MSL is delighted to partner with NPL to bring this potentially powerful technology to the Pacific. It is another beautiful example of improvement in measurement giving us access to depths of information that in turn push the limits of our metrology. Not only that, but we see precision measurement underpinning our aspirations for a sustainable future. Our earliest timekeeping devices - calendars - allowed us to live according to the rhythms of our natural world. And now the next generation of clocks is unlocking a new richness of insight into our planet.”
“We are very excited to collaborate with NPL and MSL on this project,” says Dean Veverka, CTO of Southern Cross Cables limited. “Southern Cross has a proud history of supporting initiatives designed to benefit the Pacific Island communities, we are thrilled to continue this through the development of NPL’s technology and the first trial of this in the Pacific. The 45,000km of the Southern Cross cable ecosystem spans the Pacific three times and once this technology is implemented the societal impact that early detection of seismic activity will have on the Pacific communities can be life changing.”
Read about previous work in this area
24 Apr 2024