Add Yahoo as a preferred source to see more of our stories on Google. Rip tides can be a dangerous – even deadly – for the uninitiated. Inexperienced swimmers are swept out to sea by the currents, ...

Air rings blown by dolphins swimming underwater and rings of smoke emitted by jet engines are just two examples of vortex rings. These doughnut-shaped structures and their mesmerizing movement have ...

“Spirals of nature. This is yesterday’s tornado rip that formed into an underwater vortex. Invisible to see from land, but perfectly visible by drone - which is what makes them so dangerous to ...