BBC: Researchers in Australia have declared treacherous ocean currents the nation's deadliest natural hazard ahead of bushfires and floods.
Rip currents are strong, narrow channels that pull the unwitting away from the shore and some move faster than an Olympic swimmer.
"The way they work on surf beaches, the white water - the breaking waves - bring water to the beach," said Rob Brander, a geomorphologist -someone who studies the way the ocean and the land interacts - at the University of New South...