surf safety

YEAR 9 OED 

WATER SAFETY AND SURF AWARENESS

Water safety is an important part of OLATS and your everyday life. We spend a large amount of time in the ocean when surfing and it is important that we have the knowledge and skills to enjoy the ocean safely. 

This unit will cover the following topics:

-       The different types of waves

-       Surf Environment Dangers

-       Types of rips and effective ways to identify and escape rips

-       Beach flags

-       Water hand signals and communications

-       Rescues 

Waves

 Waves are formed by the wind blowing across the surface of the ocean. The size of the waves is determined by three factors.

1.     The intensity of the wind

2.     The length of time the wind blows

3.     The distance the wind blows

The longer and stronger the wind blows, the greater the wave action, until distinct lines of swell are formed. These swell lines tend to cross the ocean in groups or sets.

Formation of waves

Wind Speed- The greater the wind speed the larger the wave.

Wind Duration- The longer the wind blows the larger the wave

Fetch- The greater the area the affects the larger the wave.

Identify three factors that determine the size of a wave

Wave height is affected by wind speed, wind duration (or how long the wind blows), and fetch, which is the distance over water that the wind blows in a single direction.

Q-Explain the difference between a spilling, plunging and surging wave.

A-A surging breaker will cause the most erosion because it slams into the beach at full speed. Spilling and plunging breakers slow down as they drag across the seafloor, so their energy is dissipated over a wider zone. 

Waves- Research Questions

Waves come in all shapes and sizes. They can be powerful and unpredictable. Having a good understanding of waves and how they are formed will help keep you safe at the beach.

Q-Explain where waves come from.

A-Waves are most commonly caused by wind. Wind-driven waves, or surface waves, are created by the friction between wind and surface water.

Q-Explain how waves break.

A-Waves break when the shape of the wave becomes too steep and this usually happens as waves travel from deep water to shallow water.

Q-Explain the difference between wind swell and ground swell.

A-Ground swell” refers to a swell that has a wave period of roughly 12 seconds or higher. Wind swell” refers to a swell that typically has a wave period between 1-11 seconds. Wave period is measured in the seconds between each wave.

Q-What is the best wave for beginner surfers to learn on? Why?

A-For beginners, it's crucial to start with small to medium-sized waves. These waves typically range from 1 to 4 feet in height

Q-What is the best wave for advanced surfers to surf on? Why?

A-An advanced surfer will look for a larger, faster, more powerful, preferable hollow a-frame. t's important that the wave starts breaks continuously from one position and peels along its length without other sections breaking. This lets a surfer ride along the unbroken face. 

Surf Environment Dangers.

There are endless dangers when it comes to coastal environments. These dangers can be easily avoided if appropriate planning, preparation, care, skills and techniques are consistently used when at such environments.

Complete the table below by placing appropriate dangers in its correct column.

Rips

Rip Currents

·       A rip current is a body of water moving out to sea.

·       Rips DO NOT pull you under the water. People can drown because they attempt to swim against the rip, become exhausted and are unable to stay afloat.

Five common signs of a rip current are:

·       Discoloured brown water, due to sand which has been stirred up from the bottom.

·       Foam on the surface extending beyond the break.

·       Waves breaking further out on both sides of the rip

·       Debris floating seaward

·       

A rippled appearance, where the surrounding water is generally calm.

Identify and Circle the Rip on the image above.

There are three main types of rip currents:

·       Topographic - will remain in the same area for months or even years.

·       Fixed - accompanied by a hole or gully on the base of the ocean floor. May remain for hours or months.

·       Flash - temporary in nature. Flash rips appear suddenly, without any warning.

Escaping a Rip

If caught in a rip:

·       Do not panic

·       Ride the rip out from the beach

·       Swim parallel to the shore for 30-40 metres in the same direction as the ocean current

·       Return to the shore when conditions allow

If you cannot escape:

·       Signal for assistance by raising one arm

·       Conserve your energy, float on your back until assistance arrives.

What is a rip?

A rip current is a specific type of water current that can occur near beaches where waves break. A rip is a strong, localized, and narrow current of water that moves directly away from the shore by cutting through the lines of breaking waves, like a river flowing out to sea

How can you identify a rip?

1. Deeper and/or darker water.

2. Fewer breaking waves.

3. Sandy coloured water extending beyond the surf zone.

4. Debris or seaweed.

5. Significant water movement.

Explain the best way to get out of a rip.

Let the current take you out the back and then swin to whatever side your closer to and you could catch a wave back in or just swim, if you are an unexperienced swimmer swim sideways to the closest side away from the rip.

Identify and describe the three types of rips.

-       Channelised Rips - There are many different kinds of rips that occur on beaches and they can have different visual clues. The most common type is a channelized rip. These rips occupy deep channels between sand bars and they can stay in place for days, weeks and even months. These are the classic ‘dark gap’ rips and may also erode a telltale embayment along the shoreline

-       Boundary Rips  Boundary and structural rips are found against headlands and other structures like jetties and piers that reach out into the ocean and lakes. These rips are generally channelised and can appear as dark gaps of deeper water.

-       One of the most dangerous and unpredictable rips is the flash rip. These rips can form quickly and without warning often as a result of a sudden increase in wave size or frequency. They are short-lived and can form and disappear at different locations along the beach and appear as turbulent streaks of water and sand.

Lateral Currents

Lateral currents are movements of water along the shoreline. They are caused by waves coming into the shore on an angle and pushing the water down the length of the beach in one direction. They can be dangerous as they can pull you into rocks, rips and out to sea. If you are caught in a lateral current, try and regain your footing and return to shore.

Sandbanks/sandbars

Sandbanks are submerged banks of sand near the shore. The water tends to be shallower on sandbanks. It is important to no dive on sandbanks and to be mindful of the depth when getting off your surf board. Be aware of stepping off a sandbank into deep water. 

Tides

Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun, and the rotation of the Earth. This means that the depth of the water will change depending on the tides.

 At low tide, there is less water over the ocean bottom and at high tide there is more water. The time of high tide and low tide change every day- tide times are not the same each day so it is important to check the tides of a location before entering the water. 

Tides can affect the rips and currents. Rips and currents can change in direction and strength depending on whether the tide is going in or out.

Undertow

Patrolled 

Sorrento Ocean Beach

Portsea Beach

Frankston Beach

Mills Beach, Mornington

Mount Martha Beach

Gunnamatta Beach

Point Leo Surf Beach

Port Melbourne

South Melbourne

Sandrige

Williamstown

Elwood

St Kilda

Queenscliff 

Unpatrolled 

St Kilda Marina

Webb Dock

St Kilda Pier

Statin Pier

St Kilda Pier-Port Melborne

Middle Park

Squeaky beach

An undertow is similar to rip. A rips is where the water flowing back to sea.  An undertow is where the water cannot find a weaker place to flow back out to sea, but instead the water flows down and under the waves and back out to sea. If you feel a strong undertow, move closer into the shore, if you fall over regain your footing or swim along with the flow of the undertow until it weakens and return to shore. 

Rocks and Rock Shelves

It is important to aware of any rocks when entering the water. Rocks can be fully or partly submerged. They will be more visible depending on whether it is high or low tide. If you see swirling water on the surface and waves breaking when the water around it is calm- there could be submerged rocks.

Research Task

https://beachsafe.org.au/

Explain the difference between a patrolled and unpatrolled beach?

Patrolled- The Red and Yellow Flags on a beach show safe places to swim, and where lifeguards or lifesavers watch people to keep them safe. This is called a patrolled area, and the lifeguards are there to help if you or a family member/friend need help in the water.

Unpatrolled- If there are no flags on the beach, this means there are no lifeguards/lifesavers on duty and swimming at the beach is not recommended, especially if you are unfamiliar with the area and have limited swimming ability or experience.

Beach Warning Signs and Flags

Complete the table below by researching each beach sign/flag. Drawing an image in the space provided and explain the meaning of the beach sign/flag.

Beach Safety, Communications & Rescues

Draw pictures of the following communication signals

Water Signals:

Attract attention 

Remain stationary 

Go to the right 

Go to the left 

Assistance Required

Return to shore Immediately