Beachgoers could be safer thanks to new technology that could provide real-time updates on rip currents.
Rip currents are narrow, fast-moving sections that travel offshore. They can reach speeds of 2.5 meters per second, which is faster than the fastest Olympic swimmer.
NIWA and Surf Life Saving New Zealand (SLSNZ) have developed a state-of-the-art rip current identification tool using artificial intelligence (AI) and deep learning. The tool showed about 90% accuracy in detecting rip currents in videos and images in tests. The work has been published in the journal Remote Sensing.
NIWA coastal scientists Dr Christo Rautenbach and Neelesh Rampal say the technology has been tested on a wide variety of images from different coastal locations and they hope beachgoers will eventually use it to alert them of rip currents.
“We hope that by using cameras and drones at beaches, the tool will be able to scan video footage and alert people to the presence of rip currents. Even surf lifeguards can struggle to identify reefs, depending on the beach and environmental conditions. Plus, some beaches are remote or really big, so surf lifeguards can use all the extra help they can get!” said Dr. Rautenbach.
The technology was developed by feeding millions of coastal aerial images into the AI model, along with rainfall and artificial fog data, to teach it to recognize when rips occur in real time, regardless of weather and camera angle.
Adam Wooler, Special Projects Manager at SLSNZ, says technology will be very important to people when they are out enjoying our beautiful coastline.
“This is just the beginning of our research together and our goal is to build more effective, accurate and reliable safety tools for New Zealand’s beaches. Rip currents can sweep even the strongest swimmers out to sea – 90 people drowned in New Zealand last year, 25 of them on beaches, so we’re hoping this technology helps reduce that number significantly, ” said Wooler.
Rip currents are reported to be the most dangerous safety risk for beachgoers worldwide. An Australian study published in 2013 showed that they killed more people on Australian territory than bushfires, floods, cyclones and shark attacks combined.