A rip current is a narrow, powerful current of water running perpendicular to the beach, out into the ocean. These currents may extend 200 to 2,500 feet (61 to 762 m) lengthwise, but they are typically less than 30 feet (9 m) wide. Rip currents can move at a pretty good speed, often 5 miles per hour (8 kph) or faster. Rip currents are often called "riptides," but this is inaccurate due to "tides" being the rising and falling of water levels in the ocean. They are also often mistaken for undertow, which is actually a current of water that pulls one down to the ocean bottom. Rip currents travel along the surface of the water, pulling one straight out into the ocean, but not underneath the water's surface. It is possible for one to get knocked off his or her feet in shallow water, however, and may end up being pulled along the ocean bottom if they thrash around and get disoriented. If relaxed, the current should keep the individual near the surface.
Rip currents are responsible for about 150 deaths every year in the United States. In Florida, they kill more people annually than thunderstorms, hurricanes and tornadoes combined. About 80 percent of all beach rescues are related to rip currents; it is the number one killer of swimmers on the beach. (Sharks typically kill about 6 people a year globally.)
How they are Created
Rip currents are created when water returns to the ocean through channels carved out by waves of different strengths crashing into the shore. They most typically form at low spots or breaks in sandbars, and also near structures such as groins, jetties and piers. (In some places the waves are strong and in others they are weak; these differing wave intensities carve out channels in sand bars that lie just off the beach. Water follows the path of least resistance (through these channels) as it returns to the ocean. This creates a strong and often very localized current. The currents usually move at one to two feet per second but stronger ones can pull at up to eight feet per second. Heavy breaking waves can trigger a sudden rip current, but rip currents are most hazardous around low tide, when water is already pulling away from the beach. Hurricanes, widely spaced swells, and long periods of onshore wind flow can also facilitate stronger currents. These conditions often also create larger waves, which sometimes draw more people into the water.
Identifying Rip Currents
- a channel of churning, choppy water
- an area having a notable difference in water color (murkier from sediments or darker because of greater depths)
- a line of foam, seaweed, or debris moving steadily seaward
- a break in the incoming wave pattern
- an offshore plume of turbid water past the sandbars
If You Are Caught in a Rip Current
If you find yourself caught up in a rip current, it's crucial to remain calm. Most often it occurs in waist deep water, which may add to people being caught off-guard. Often the first instinct may be to swim against the current back to shallow waters, which in most cases will only wear you out, even for the strongest swimmers. The current is too strong to fight head-on. Most people panic and exhaust all their energy straightaway because of how fast they find themselves being swept out to sea.
Swim sideways, parallel to the beach, which takes you out of the rip current. Rip currents are rarely more than 30 feet wide. Once you're out you can swim back to shore. Sometimes it may be too difficult to swim sideways while you're being dragged through the water, so you should float or tread water and let the current carry you out (it will dissipate after a while, where you can get clear of it and return to shore). The most important thing is to conserve your energy. If you don't think you can swim all the way back to the beach, get past the rip current and tread water. Call for help, signal to people on the beach, and if all else fails, wait for the waves to carry you in.
If Someone Else is Caught in a Rip Current
If you're on the beach and you spot somebody else caught in a rip current, call for help from a lifeguard or the police. Don't immediately dive in and swim out to the person.
- ↑ 1.0 1.1 1.2 Harris, Tom (n.d.). How Rip Currents Work. Science.howstuffworks.com. Retrieved on 2008-10-16.
- ↑ 2.0 2.1 2.2 2.3 Livescience (27 July 2008). Rip Currents: The Ocean's Deadliest Trick. Livescience.com. Retrieved on 2008-10-16.
- ↑ 3.0 3.1 Weather.com (n.d.). How, When, Where Rip Currents Form. Weather.com. Retrieved on 2008-10-16.
- ↑ 4.0 4.1 NCseagrant.org (n.d.). Rip Currents: Don't Panic. NCseagrant.org. Retrieved on 2008-10-16.