Innovative system for sea rescue. Researchers have developed new calculation method
Countless people drown on the high seas every year when ships sink or aeroplanes crash. The ensuing rescue can prove difficult purely because rescuers only have a short space of time to save the people in the water. The likelihood of finding a person alive decreases significantly after six hours. In addition to the tide and volatile weather conditions, there are also unstable coastal currents that hamper rescue missions. Researchers at ETH Zurich and MIT in Boston have developed a calculation method to speed up the search during sea rescues. An international team led by George Haller, professor of non-linear dynamics at ETH Zurich, has broadened the previously used search strategies with new findings about unstable currents. Using coastguard data as the basis, an algorithm was developed to predict the points on the sea’s surface that people and objects are pushed towards. Until now, laborious models of sea dynamics and weather reports were used to predict the path that a floating object would take, which is often impossible to do with precision in coastal waters. As a result, searches begin at the wrong location and crucial time is lost. Researchers have now discovered through calculations that objects floating on the sea’s surface gather in specific lines that are similar to curves. Named TRansient Attracting Profiles (TRAPs), i.e. profiles with temporary attraction, they cannot be seen with the naked eye but can be identified using the new algorithm. By doing this, routes for rescue missions can be planned more quickly and precisely. A successful test of the search algorithm near to Martha’s Vineyard, off the north-east coast of the US, saw how buoys and dummies that were cast adrift gathered along the calculated curves. Another benefit of the method is that larger objects floating on the sea’s surface, such as a spreading oil slick, can also be calculated.