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A rip current is a strong flow of water returning seaward from the shore. It is often mistakenly called a "rip tide" or "riptide", though the occurrence is not related to the tides. Colloquially a rip current is known simply as a rip. Although rip currents would exist even without the tides, tides can make an existing rip much more dangerous (especially low tide). Typical flow is at 0.5 meters per second (1-2 feet per second), and can be as fast as 2.5 meters per second (8 feet per second). Rip currents can move to different locations on a beach break, up to a few hundred feet a day. They can occur at any beach with breaking waves, including the world's oceans, seas, and large lakes such as the Great Lakes in Canada and the United States. Impact from a water drop causes an upward rebound jet surrounded by circular capillary waves. ...
For the three letter acronym, see SEA. For the ancient Jewish unit of volume, see Seah (unit). ...
Shore A shore or shoreline is the land at the edge of a large body of water, such as an ocean, sea, or lake. ...
This article is about tides in the Earths oceans. ...
The metre, or meter (symbol: m) is the SI base unit of length. ...
Look up second in Wiktionary, the free dictionary. ...
A foot (plural: feet or foot;[1] symbol or abbreviation: ft or, sometimes, ′ – a prime) is a unit of length, in a number of different systems, including English units, Imperial units, and United States customary units. ...
Animated map exhibiting the worlds oceanic waters. ...
For the three letter acronym, see SEA. For the ancient Jewish unit of volume, see Seah (unit). ...
Blowdown Lake in the mountains near Pemberton, British Columbia A lake (from Latin lacus) is a body of water or other liquid of considerable size contained on a body of land. ...
The Great Lakes from space The Laurentian Great Lakes are a group of five large lakes in North America on or near the Canada-United States border. ...
Recognizing a rip current
 A sign warns hikers on the trail to Hanakapiai Beach. There are signs to look for in the water to see if a rip current is present. Rip currents can be recognized by unusually calm waters, caused by the channel of water flowing out. The color of the water may be different from the surrounding area. Also, the waterline is lower on the shore near a rip current. It is advisable to look for the existence of a rip current before heading into the water. [1] [2] Image File history File linksMetadata Download high resolution version (442x888, 102 KB) Summary Super Crop showing only the sign. ...
Image File history File linksMetadata Download high resolution version (442x888, 102 KB) Summary Super Crop showing only the sign. ...
A sign warns hikers on the trail to Hanakapiai Beach. ...
Uses Rip currents can also be extremely useful for surfers as they save the effort of having to paddle out to catch a set. They can also be used by lifeguards (swimming or on paddleboards), who can use them to get out from the shore to perform a rescue much quicker than they could by swimming/paddling through the waves.
Dangers Such currents can all be extremely dangerous, dragging swimmers away from the beach and leading to death by drowning when they attempt to fight the current and become exhausted. Swimming is the method by which humans (or other animals) move themselves through water. ...
Ninety Mile Beach Australia. ...
A current is a movement or flow of fluids, especially water in a river or ocean. ...
Fatigue is a feeling of excessive tiredness or lethargy, with a desire to rest, perhaps to sleep. ...
Although rare, rip currents can be deadly for non-swimmers as well: a person standing waist deep in water can be dragged out into deeper waters, where they can drown if they are unable to swim and are not wearing a flotation device. It has been suggested that floatation suits be merged into this article or section. ...
Rip currents cause approximately 100 deaths annually in the United States, more than all other natural hazards except heat and floods. Over 80% of rescues by surf beach lifeguards are due to rip currents totaling 18,000 lifeguard rescues a year. A flood (in Old English flod, a word common to Teutonic languages; compare German Flut, Dutch vloed from the same root as is seen in flow, float) is an overflow of water, an expanse of water submerging land, a deluge. ...
It has been suggested that this article be split into multiple articles. ...
Image File history File links One of the mechanisms of a rip current: breakers cross sand bars off the shore but the addtional water travels back to sea throgh the gap in the sand bars creating a fast current. ...
Image File history File links One of the mechanisms of a rip current: breakers cross sand bars off the shore but the addtional water travels back to sea throgh the gap in the sand bars creating a fast current. ...
Causes and occurrence While the precise conditions leading to a rip current are not known, the general picture is as follows. When wind and waves push water towards the shore, the previous backwash is often pushed sideways by the oncoming waves. This water streams along the shoreline until it finds an exit back to the sea. The resulting rip current is usually narrow and located in a trench between sandbars, under piers or along jetties. While a common misconception is that a rip occurring under the water, instead of on top — an undertow — is strong enough to drag people under the surface of the water; the current is actually strongest at the surface, and can dampen incoming waves, leading to the illusion of a particularly calm area, luring some swimmers in. In geography, a bar is a linear shoaling landform feature within a body of water. ...
For the type of foundation, see Deep foundation. ...
Alternate meanings: See Jetty (web server) Alternate meanings: See Jettying in buildings The term jetty, derived from the French jetie, and therefor signifying something thrown out, is applied to a variety of structures employed in river, dock and maritime works which are generally carried out in pairs from river banks...
Rip currents are stronger when the surf is rough (such as during high onshore winds, or when a strong hurricane is far offshore) or when the tide is low. Look up surf on Wiktionary, the free dictionary. ...
For the 1928 film, see The Wind. ...
This article is about weather phenomena. ...
Offshore has two principal meanings: Physical - in the sea away from the shore; not on the shoreline but out to sea. ...
This article is about tides in the Earths oceans. ...
A more theoretical description involves a quantity known as radiation stress. This is the force (or momentum flux) exerted on the water column by the presence of the wave. As a wave shoals and increases in wave height prior to breaking, radiation stress increases. To balance this, the mean sea surface (the water level with the wave averaged out) decreases. This is known as setdown. As the wave breaks and continues to reduce in height, the radiation stress decreases. To balance this force, the mean sea surface increases - this is known as setup. As a wave propagates over a sandbar with a gap (as shown above), the wave breaks on the bar, leading to setup. However, the part of the wave that propagates over the gap does not break, and thus setdown will continue. Thus, the mean sea surface over the bars is higher than that over the gap, and a strong flow will issue outward through the gap.
Rip currents can potentially occur wherever strong longshore variability in wave breaking exists. This variability may be caused by sandbars (as above) or even by crossing wave trains.
Surviving an encounter with a rip current When caught in a rip current, one should not fight it, but rather swim parallel to the shoreline in order to leave it. If you see a person caught in one, yell at them to do so. Floating until the current disperses into deeper waters is another method of surviving such a dangerous incident, but it may leave the swimmer farther out from shore. Parallel is a term in geometry and in everyday life that refers to a property in Euclidean space of two or more lines or planes, or a combination of these. ...
There are several meanings of float: an air-filled vessel that floats on water, such as some types of lifeboats buoyancy float (project management) floating currency floating exchange rate floating point, a datatype in computer science free float of company stock insurance (investable policyholder funds) root beer float: ice cream...
Disperse is a Christian Rock band from Southern Indiana. ...
Safety tips Posted warnings, where available, should always be heeded. It is advisable to stay at least 100 feet away from piers and jetties, which impede waves, encouraging rip currents to form. Also, check the local newspaper and internet for tide timetables. (Beware that tides can be substantially different at beaches relatively close to each other.) Never go into the water without lifeguard supervision from -2 to +4 hours of the daily maximum low tide -- especially at night..
See also This page is a candidate to be copied to Wiktionary. ...
External links - Rip Current Safety (US National Weather Service)
- United States Lifesaving Association, Rip Currents
- Rip Currents - Everything a swimmer needs (pictures too) on just one page
- Rip Current Awareness (New Jersey Marine Sciences Consortium)
- Rip currents: Going with the flow (a study reveals that Rip Currents are much more complicated than was previously thought, New Scientist, 27 June 2007)
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