If you're headed to the beach this weekend, here's everything you need to know about staying safe in the sea. Rip tides, also know as rip currents or undertows, are long, narrow bands of water that flow quickly away from the sea. Swimming in one of these seemingly calm stretches of water, which usually form in between crashing waves, can pull swimmers away from the shore rapidly. Flash rip: A rip current can form suddenly and vanish just as fast due to decreasing water levels or increasing wave heights.
Fixed rip: A fixed rip, sometimes formed between sand bars, can stay in the same place for days, weeks, or even months. Permanent rip: In a place with a permanent obstacle like a reef, a rip may be ever present. Dangerous currents can occur anywhere there are breaking waves, including large lakes.
One of the best visual identifiers of a rip current is to look out for gaps between the waves. A calmer body of water in an otherwise choppy sea might look safe to splash in, but these small breaks are often rip tides. Look out for discoloured water near the shore. A strong current can also pick up sand and sediment, leaving a noticeable jet of darker water near the shore.
You might also be able to see the rip current picking up things like seaweed, forming a line of debris which moves steadily seaward. Finally rip currents are also common in areas with sand bars both surface and submerged , piers, jetties, groins, and anything else that sticks out from the beach that could catch a longshore current and cause it to start flowing away from shore.
Unfortunately, all this will do is tire you out and use up valuable energy. In the next section, we'll examine this water flow in greater detail and find out what you should do if a rip current pulls you out into the ocean.
In the last section, we saw that rip currents occur when water rushes through a low point in a sandbar. Since waves keep pushing more water into the basin between the sandbar and the beach, the rip current may continue for several minutes, or even several hours.
Some rip currents are brief occurrences, but others are long-term fixtures of an area. Typically, the strongest part of a rip current is the direct line between the water's edge and the sandbar opening, but the current will also pull in water from either side of the basin. In this way, a rip current might pull you sideways , parallel to the beach, before it pulls you outward, away from the beach.
Once the receding wave makes its way through the sandbar opening and meets up with water at its own level, its pressure immediately drops.
Overall, the water flow pattern has a mushroom shape. Depending on its severity, you may be able to see a rip current from the beach. Strong rip currents disrupt incoming waves and stir up sand from the ocean floor.
When you're at the beach, keep an eye out for narrow, muddy streaks in the ocean where there aren't any waves breaking. If you get caught up in a rip current, it's crucial that you keep your wits about you.
Your first instinct may be to swim against the current, back to shallow waters. In most cases, even if you're a strong swimmer, this will only wear you out. The current is too strong to fight head-on. Instead, swim sideways , parallel to the beach see illustration below. This will get you out of the narrow outward current, so you can swim back in with the waves helping you along.
If it's too hard to swim sideways while you're being dragged through the water, just wait until the current carries you past the sandbar. The water will be much calmer there, and you can get clear of the rip current before heading back in. People drown when they thrash about in the water or expend all of their energy swimming. To survive a rip current , or any crisis in the water, you have to keep calm, and you have 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 you're on the beach and see 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. It's too risky to swim out there yourself unless you have a raft, boogie board or life preserver with you.
The most effective way to fight rip currents is to follow basic swimming safety rules: Never go in the ocean alone , and if you aren't a strong swimmer, stick to shallow waters although even shallow waters can be dangerous.
Ideally, you should only swim in areas where there is a lifeguard or strong swimmer on the beach who can keep an eye on you. If you plan to swim in the ocean anytime soon, it's a good idea to learn everything you can about rip currents. After all, they are the beach's number-one killer. Sign up for our Newsletter! A swimmer can also let the current carry him or her out to sea until the force weakens, because rip currents stay close to shore and usually dissipate just beyond the line of breaking waves.
Occasionally, however, a rip current can push someone hundreds of yards offshore. The most important thing to remember if you are ever caught in a rip current is not to panic. Home Education Currents Rip Currents. Rip Currents Currents Tutorial.
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