Issue link: https://maltatoday.uberflip.com/i/682623
maltatoday, SUNDAY, 22 MAY 2016 AVIATION, SHIPPING & LOGISTICS VII the 2012 event at Queen Charlotte Islands, Canada, highlighted weaknesses in this approach. For the 2012 tsunami from the Queen Charlotte Islands earthquake, the lack of deep ocean data meant a tsunami warning and evacuation was issued for some of Hawaii's coastlines, though the event turned out to be smaller than predicted. This emphasized the need for more densely spaced deep ocean observing capabilities. Even just a few more observations in the right places would have enabled the scientists to improve their estimates of the tsunami size. A solution arrives by chance The potential solution to this problem came about by chance. In 2010, I was running an experiment with colleagues using high-accuracy GPS on the UH research vessel Kilo Moana. On its way to Guam, the Kilo Moana was passed by the tsunami generated by the magnitude 8.8 earthquake in Maule, Chile, on February 27 of that year. In the deep ocean this tsu- nami wave was only about 10 cm (about 4 inches) high with a wavelength of more than 300 miles. Its passage would normally have remained unde- tected, lost amid the several meters of heave of the ship in the regular waves. How- ever, careful analysis of the data collected by the GPS proved that the system we had in place accurately recorded the tsunami signal. The ability of the GPS-based system to detect tsunamis among the much larger ocean waves comes from the distinct difference between their respective intervals, called pe- riods. Ocean swells that rock even the largest ships come at intervals of 15 to 20 seconds. Tsunami swells, however, take 10 to 30 minutes to pass – or even longer. Looking at the height of the ocean's surface – and of a ship afloat – over this longer time period, the normal fluctuation of ocean swells cancel each other out. The data then reveal the long- period perturbations caused by a passing tsunami. The recognition that tsu- namis can be detected from ships is a game-changer. There are thousands of large cargo ships sailing the ship- ping lanes across the world. Rather than building and deploying many more of the expensive traditional sensors to try to fill gaps in coverage, it makes sense to use the ships that are already out there. This new approach offers a cost-effective way of acquiring many more observations to augment the current detection networks. While these new observations will not neces- sarily lead to quicker detection of tsunamis, they will lead to more accurate predictions be- ing made more quickly. Working with the NOAA Tsunami Warning Cent- ers ensures that the newly installed network provides their scientists with the most useful data to help with their predictions. Collaborating with industry partners, we will be developing a new version of the shipboard package that can be deployed easily on a much greater number of ships. The new ship-based detec- tion network is the first step to- ward the creation of the dense global observing network needed to support the efforts of all tsunami warning centers to provide the best possible predictions of tsunami hazard to coastal communities. James Foster is Associate Researcher at the University of Hawaii detect tsunamis: cargo ships Five years ago: an aerial view of Minato, Japan, after the earthquake and tsunami. Lance Cpl. Photo: Ethan Johnson/U.S. Marine Corps Logistics rebrand Coupled with the rebrand- ing, Eurocargo Logistics is also launching a new com- pany website this month, featuring information on the company's history and showcasing features of each service provided. For more information, log on to: www.eurocargo.com.mt