Wherever waves break, surfers will ride them.
Surfing is usually associated with warm ocean beaches like those found in the U.S. states of Hawaii and California, and countries such as Australia. Surfers, however, do not limit themselves to warm weather or ocean waves. Surfers dust a foot of snow off their surfboards to chase waves off the coast of Antarctica. They trek through jungles to pristine beaches in Southeast Asia. They share the water with great white sharks in South Africa. They even ride the “silver dragon,” the giant tidal bore of China’s Qiantang River.
Surfing is possible in all these places because the concept is simple. A breaking wave, a board and a brave athlete are all that is needed for the sport. (Sometimes, you don’t even need the board. This is called bodysurfing.)
The concept is simple, but the practice is not. Surfers paddle or are towed in to the surf line, the area of open water where waves break as they near a coast. There, surfers sit on their boards and watch waves roll in to shore. Experienced surfers assess several different qualities in every wave. A wave must be strong enough to ride, but not dangerous enough to toss the surfer as it breaks. Surfers must be able to ride and safely exit the wave—not too close to shore or rocks. For river waves or those at artificial surfing facilities, surfers watch waves develop and jump right into the breaking wave.
When surfers see a wave they can ride, they paddle quickly to catch the rising wave. Just as the wave breaks, the surfers jump from their bellies to their feet, crouching on their boards. Being able to stand up is the mark of an experienced surfer. Surfers ride the wave as it breaks toward the shore. As the wave falls and loses power, surfers can exit the wave by turning their boards back toward open water. Surfers can also exit by simply lowering themselves back to their boards and paddling back out. Of course, the force of the wave can end surfers’ rides by crashing on or over them. Surfers can be tossed above a wave or below it. Then the process of paddling out to the surf line begins again.
Surfers must be aware of their physical skills as well as the environment. There are several different types of surfing (longboard, shortboard or big-wave, for instance). Each requires a different sets of skills. All surfers must be aware of weather patterns and topography, or surface features, of the shore. Experienced surfers are also familiar with bathymetry, the depth of the body of water. They must be strong swimmers. Surfers must also have an excellent sense of balance and be able to quickly react to changes in the environment. (For this reason, skateboarding is a common hobby among surfers—and surfing is a common hobby among skateboarders.)
Men and women from all over the world practice surfing, and the surfing community shares a concern for the ocean environment.
Surfing depends on the science of hydrodynamics. Hydrodynamics is the study of water in motion. Oceanographers, ship captains, and engineers must all be familiar with hydrodynamics.
Surfers seek out strong waves called swells. Swells are stable waves that form far away from the beach. Swells are formed by storm systems or other wind patterns.
Two things determine the strength of a swell. First, swells are influenced by the strength of the winds that form them. Swells can help predict how strong a storm is as it approaches land. Most storm systems that form far out to sea never reach land with much strength. Sometimes, however, they do. These storms arrive as hurricanes or typhoons. Hours before a hurricane approaches shore, large and frequent swells signal its arrival. Surfers have been known to ignore hurricane warnings and stay out on stormy beaches because the swells are so frequent and strong.
The second feature that influences swell strength is the wind’s fetch. Fetch is a geographic term that describes the amount of open water over which a wind has blown. The length of fetch is why ocean swells are usually much stronger than lake swells. In the open ocean, a wave's fetch can be thousands of kilometers.
Weather forecasting can predict both elements of swells—offshore storm systems and the length of a wind’s fetch. Surfers consult these surf zone forecasts and can chase swells all over the world.
Not all waves are swells, however. Most are smaller, more unpredictable waves, called wind waves. Swells are a type of wind wave (they are caused by wind), but the term usually refers to waves caused by wind with a shorter fetch. Wind waves have more chop than swells. Chop is the amount of short, irregular shifts in wave formation. Choppy water can be dangerous for surfers because the direction and strength of waves change from minute to minute.
Both wind waves and swells must break (crash) for them to be of use to surfers. A calm day with no wind may be perfect for beachgoers, but makes for lousy surfing weather. Surfers need a reliable set of breaking waves, which requires moderate offshore wind.
The most significant factor in how a wave develops is the underwater topography. Topography is the surface features of an area. Waves can be weakened or strengthened by topographical features of the seabed.
Surf breaks are permanent features that cause waves to break in a predictable way. Reefs, sandbars, and large underwater boulders are examples of common surf breaks. Ocean trenches and submarine canyons can also determine how a wave breaks. Surfers must account for the presence of sea life, such as a kelp forest, a dense cluster of large seaweed. Seaweed can slow a breaking wave.
A wave breaks when its base (the water beneath the surface) can no longer sustain its height. Near shore, waves break because water gets shallower as it nears a beach. The shallower a wave base, the more likely the wave is to break. The region of water where waves begin to break is called the surf line. Waves crash forward, their tips turning frothy and white. Sometimes, a breaking wave crashes into another wave. Other waves curl in on themselves, forming a tube near the crest, or top. Many surfers consider these tubular wave breaks the most desirable to surf.
There are four major types of waves. Experienced surfers can ride all four types, although each has its own difficulties.
Rolling waves (1) are the most familiar waves, and the type most surfers prefer. These waves break in a stable pattern. Rolling waves are usually a feature of a flat, sandy shoreline. The rolling waves at Hossegor, France, on the Bay of Biscay, can reach more than 6 meters (20 feet).
Dumping waves (2) are more unpredictable. These waves are the result of an abrupt change in seabed topography. A steep underwater cliff or mountain can create dumping waves. These waves are usually limited to experienced surfers, as they are dangerous. Dumping waves can dump surfers far beneath the water’s surface with great force.
Dumping waves can be the result of point breaks. Point breaks occur when a wave hits a point of rocky shore jutting into the ocean. Agadir, on the Atlantic coast of Morocco, boasts several strong point breaks.
Dumping waves can also result from reef breaks. Reef breaks occur as waves pass over a coral or rocky reef. Reef breaks can be quite dangerous if the wave dumps the surfer on the reef. However, reef breaks provide some of the most rewarding waves. In Fiji, a reef break called Cloudbreak draws many experienced surfers.
Surging waves (3) are the most dangerous. They are most often present on steep or rocky shores. Unlike rolling or dumping waves, surging waves do not break as they near the shore. They break only at the shore itself. Surging waves are dramatic as they crash against rocky cliffs, for instance. They have the ability to throw surfers against the rock or reef, as well as drag them back to the ocean.
Surging waves are often produced by large storms. Surfers can ride waves ahead of storms or waves produced by storms hitting land far away. Surfers in western Florida, for instance, flocked to beaches as Hurricane Ike hit the western Gulf of Mexico in 2008.
Standing waves (4) are also called stationary waves. These waves are constant and do not lose strength. The factors that contribute to these waves—the topography of the region, water flow and wind patterns—do not change. Examples of standing waves are river rapids and waves created by artificial wave machines, called wave pools. In landlocked areas, wave pools (often located at water parks) allow surfers to practice without having to travel. The first wave pool in the U.S. was established in 1969 in Tempe, Arizona.
The most important piece of equipment a surfer has, or course, is a surfboard. Surfboards are usually hollow and weigh between 4 and 10 kilograms (9-22 pounds). They are usually constructed of manmade materials such as plastic and fiberglass. Most surfboards have slightly raised edges to help with balance. “Fins” beneath the rear of the board allow surfers greater control over their ride. Surfboards are divided into two models, longboards and shortboards. They are both about 5 centimeters (2 inches) thick and 48 centimeters (19 inches) wide. Their only major difference is length.
A longboard is typically about 3 meters (9 feet) long. The nose, or front part of the surfboard, is rounded. Longboards can be slightly wider and thicker than shortboards, making them more stable and buoyant (able to stay afloat). This stability serves two functions. First, it allows surfers to catch smaller, weaker waves. This makes longboards excellent tools for beginning surfers. Second, stability allows experienced surfers to perform more advanced maneuvers, such as walking to the nose of the board and “hanging ten”—curling all ten toes over the side.
Shortboards are about 2 meters (6 feet) long. They have a more pointed nose, and usually have more fins than longboards. Their size and shape make shortboards less buoyant than longboards, which means the waves shortboarders catch must be strong and steep. Shortboards are much easier to maneuver. They are more difficult to ride but are popular because they allow surfers greater control.
Of course, there are as many types of surfboards as there are surfers: “funboards” (about 2.5 meters, or 8 feet, long), bridge the gap between longboards and shortboards; “fish” boards have a split tail end; “guns” are teardrop-shaped and are ideal for big-wave surfing.
Both longboarders and shortboarders use other equipment. Water can make the board slippery. Surf wax is applied to dry surfboards to help surfers “stick.” Traction pads can be applied to the deck, or upper part of the board, for the same reason.
Most surfers attach a leash between their surfboard and their ankle. The leash stops the surfboard from being lost when a surfer exits a wave. Leashes prevent boards from either washing onshore or popping up and injuring other surfers.
Depending on surfing conditions (weather, wave type, and wave strength), surfers may outfit themselves with protective gear. Warm-water surfers wear modified wetsuits or swimsuits. Cold-water surfers can wear full-body wetsuits, including hoods, boots and gloves.
Ways to Surf
Longboarding and shortboarding require different skills. In addition, athletes can specialize in big-wave surfing, wakesurfing, or bodysurfing.
Longboards allow surfers greater balance than any other kind of surfboard. Because of this balance and stability, longboarders can do what looks like gymnastics on their surfboards. Longboard surfers must be adept at “walking” on their boards. Besides “hanging ten,” they can also “hang heels,” where surfers turn around and put their heels over the nose of the surfboard. Daring athletes can even do handstands on their longboards.
Shortboards allow for greater maneuverability. Shortboarders practice a variety of different turns. “Cutbacks” are turns that force the surfer back toward the breaking wave. Difficult “off the lip” turns take the surfer off the crest of the wave completely, into the air. Expert surfers can turn in mid-air.
Big-wave surfing is just what it sounds like: surfing very, very big waves. Most surfers ride waves between 3 and 6 meters (9-20 feet) high. Big waves can be four times that high, more than 25 meters (82 feet) tall. These waves usually only form in the open ocean, so big-wave surfers cannot be found on lakes or rivers. Experienced big wave surfers practice “tow-in surfing,” where a boat or other watercraft tows surfers past the surf line to where enormous ocean swells break. When big-wave surfers catch a wave, they drop the towline, the boat or watercraft pulls away, and the surfers brave the mountain of water on their own.
Big waves can be formed by underwater topography. The spectacular waves at Mavericks, near Half Moon Bay, California, are the result of an unusual formation on the Pacific Ocean seabed. Bathymetric maps completed in 2007 revealed that the area leading up to Mavericks is an upward slope or ramp. The waves coming up the ramp have more time to form and can draw on the calmer waters from troughs on either side of the ramp. The result is waves that regularly reach 9.15 meters (30 feet) high. Big wave surfers from all over the world travel to Northern California to surf Mavericks.
Wakesurfing is like water skiing on a surfboard. Wakes are the wave trails left by boats or other heavy objects traveling quickly through the water. Surfers on very short boards trail behind boats and surf in the wakes they create.
In the Gulf of Mexico near Galveston, Texas, huge ships called oil tankers are a common sight. Tankers deliver petroleum to and from facilities at the port at Galveston. Wakesurfers take advantage of these tankers. Boats trail the tankers, and surfers “tank surf” the wakes. The wakes are moderate in size—rarely more than 1.5 meters (5 feet) high—but they can be 1.5 kilometers (nearly a mile) long.
Bodysurfing is the art and science of riding down a breaking wave without a board. Bodysurfers often wear specialized swim fins, or plastic flippers attached to their feet. They can use similar devices on their hands. Bodysurfers use their torso, or upper body, as the board. Approaching a wave, bodysurfers throw one arm straight above the water and use their other arm and legs to steer and stay buoyant in the water. Because the human body is not as large or buoyant as a surfboard, bodysurfers ride slower waves closer to shore. This does not, however, make bodysurfing easier or less dangerous than other forms of surfing.
All forms of surfing require the athlete to be an excellent swimmer. Boards can be broken or lost, and surfers need to be able to swim back to shore. Waves and currents are extremely strong, and drowning is a risk of the sport. Drowning can occur by being pulled under the water and by being dragged out to sea. Although surfboards are buoyant, they cannot be relied upon as flotation devices.
Every surfer in every type of surfing will eventually experience a wipeout. A wipeout is the act of falling off a surfboard while riding a wave. Wipeouts are more common where waves are larger, stronger or more unpredictable. Waves can throw surfers to the seabed or back to the open ocean. Waves can also toss surfers onto underwater rocks or reefs. (This is what makes point breaks and reef breaks dangerous.)
In big-wave surfing, wipeouts are even more dangerous. The tremendous force of the waves can force a surfer as much as 15 meters (51 feet) underwater. Worse, the churning waves can block light and make it difficult for the surfer to tell which way is up. Big-wave surfers need to react quickly to wipeouts.
Even experienced big-wave surfers are at risk. Mark Foo, an American surfer from Hawaii, died at Mavericks in 1994. He wiped out in what was, for him, a moderate-size wave (6 meters, or 20 feet). After wiping out, his leash caught on the rocks below the surf, and Foo drowned. Foo was an outstanding athlete who helped popularize the sport of big-wave surfing, and his death was a shock to the community.
Sea life can also pose a danger to surfers. Kelp is large seaweed that can grow 9 meters (30 feet) tall. Kelp forests grow from the ocean floor, and their tops rest on the ocean surface. Kelp poses many dangers to surfers. It can slow waves, tangle surfers, provide habitat for predators such as sharks, and obscure the view of the ocean floor. Surfers who cannot accurately judge the depth and topography of the ocean floor are in danger. This is why many surfers prefer to surf in fairly clear water.
Animals in the surf can put surfers in danger. Bull sharks, tiger sharks, and great white sharks are probably the biggest risk. Surfers paddling on their boards can look like seals or sea turtles when viewed from below. Seals and turtles are both prey for sharks. Exploratory bites from sharks can injure or kill surfers. One of the most famous shark victims in surfing is Bethany Hamilton, an American surfer from Hawaii. She was attacked by a tiger shark in 2003 and lost her left arm. She returned to surfing as soon as she could.
Hamilton is a professional surfer, meaning she competes with other surfers for money and prizes. Professional surfing is a 20th century invention, although the sport is probably a thousand years old. Surfing was first described by European explorers of the South Pacific. Polynesians of the 18th century surfed the same spots—Hawaii, Fiji, Tahiti—that modern surfers enjoy. Just like today, both men and women participated in surfing. Unlike today, they surfed without wearing any clothes.
The earliest surfboards were about the same length as modern surfboards, but much thinner. They were probably used by surfers who paddled or rode on their bellies. Early surfboards used for standing up were much heavier than modern surfboards. Made of solid wood (such as balsa or mahogany), these boards weighed up to 90 kilograms (almost 200 pounds). They were much larger than modern longboards, reaching up to 7 meters (23 feet) long. These giant surfboards, called olos or olo boards, were created for Hawaiian royalty.
Surfing remained a hobby more than a sport until Olympic athlete Duke Kahanamoku popularized it in the early 1900s. Kahanamoku was a three-time gold medalist in swimming, competing at the 1912, 1920, and 1924 Olympics. A native Hawaiian, Kahanamoku was also an avid surfer. The governments of the U.S. and Australia invited him to demonstrate the sport, and it took hold in both places. Hawaii was not a U.S. state at the time, and Kahanamoku helped make the islands a popular tourist destination. He was the first person inducted into both the Swimming Hall of Fame and the Surfing Hall of Fame.
Kahanamoku rode large, heavy surfboards made of solid wood. Inexpensive new materials like plastic and fiberglass were introduced to surfboard design in the 1940s, making surfing even more popular and widespread.
In the 1970s and 1980s, surfers emerged as environmental activists. Surfers are among the first people who are aware of changes to aquatic ecosystems. They alert authorities to algal blooms in the Great Lakes in North America, for instance. Surfers are aware of coral bleaching, when corals lose their color. Some research suggests that sunscreen, which protects swimmers from the harmful rays of the sun, can contribute to coral bleaching. Surfers were among the first people to react to this possibility, and many responded by choosing to wear light wetsuits instead of swimsuits. This reduced the need for sunscreen.
Groups like Surfer’s Environmental Alliance are concerned with pollution and other threats to beaches and the ocean. Beach pollution can restrict access to beaches and make it difficult for surfers to use trails to the beach. Ocean pollution can make surfing dangerous and unpleasant.
Surfers have sued companies and governments to keep the coast and its waters clean. They have forced paper mills to limit runoff, oil companies to protect their undersea pipelines, and states to change the way sewage is treated.
The Surfrider Foundation, founded by Southern California surfers, is a leader in environmental protection and conservation. These surfers made surfable waves recognized as a natural resource, just like minerals, trees and petroleum.
A surfer-to-English dictionary:
avalanche = large wave or set of waves that is breaking
barrel = hollow tube of a breaking wave
dawn patrol = surfers who go out in the early morning
goofy foot = to surf with the left foot on the back of the board (regular foot puts the right foot in this position)
grommet = young surfer
hang ten = to surf with all ten toes curled over the front of the board
pearl = putting the nose (front) of the board under water while riding a wave (usually leading to a wipeout)
shaka = the gesture (fingers curled, thumb and pinky out) used by surfers for a greeting or recognition
wipeout = falling off your surfboard while riding a wave
The Endless Summer
Thats the name of the most famous surfing documentary ever made (1966). The film follows two surfers from Southern California in their trek around the world in search of the perfect wave. They go to Cape Town, South Africa; Tahiti; and Oahu, Hawaii, among other places. Other surfing documentaries include:
- The Endless Summer II (1994)
- Thicker than Water (2000)
- Step into Liquid (2003)
- Riding Giants (2004)
- Waveriders (2008)
Name That Break
- Banzai Pipeline (reef break in Oahu, Hawaii)
- Cold Hawaii (point break in Klitmoller, Denmark)
- G-Land (reef break in Bay of Grajagan, Indonesia)
- Gnaraloo (reef break in Western Australia)
- J-Bay (point break in South Africa)
sudden or quickly changing.
person who strongly and actively supports an issue or point of view.
the rapid increase of algae in an aquatic environment.
having to do with water.
to evaluate or determine the amount of.
person who participates or competes in sporting events.
tropical American tree with extremely light, strong wood, used especially for floats.
bottom layer of a structure.
representation of spatial information displaying depth underwater.
measurement of depths of bodies of water.
narrow strip of land that lies along a body of water.
debris or garbage that has washed ashore from a body of water.
to ride waves more than 6 meters (20 feet) tall on a surfboard.
to ride a wave without a surfboard.
capable of floating.
person in command of a ship or other vessel.
short, irregular shifts in wave formation.
steep wall of rock, earth, or ice.
edge of land along the sea or other large body of water.
management of a natural resource to prevent exploitation, destruction, or neglect.
tiny ocean animal, some of which secrete calcium carbonate to form reefs.
loss of symbiotic algae (zooxanthellae) in corals, leading to a loss of pigmentation.
rocky ocean features made up of millions of coral skeletons.
the top of a wave.
steady, predictable flow of fluid within a larger body of that fluid.
a sharp reversal of direction, such as a surfer turning the board back toward a breaking wave.
risky or unsafe.
the top side of a surfboard.
to show how something is done.
to die or suffocate in a liquid.
(1890 - 1968) U.S. Olympic swimmer who popularized the sport of surfing.
type of wave that breaks suddenly, dumping swimmers and pushing them to the bottom. Also called barrel or plunging waves.
community and interactions of living and nonliving things in an area.
person who plans the building of things, such as structures (construction engineer) or substances (chemical engineer).
conditions that surround and influence an organism or community.
tools and materials to perform a task or function.
person who studies unknown areas.
the length of open water over which wind is generating waves.
material made from fine strands of glass that are woven into fabric.
device fixed to the bottom of a surfboard to aid in control. Also called a strut or skeg.
short, stubby surfboard with a fish-like shape.
to predict, especially the weather.
type of surfboard about 2.5 meters (8 feet) long that combines the speed of a longboard with the maneuverability of a shortboard.
system or order of a nation, state, or other political unit.
largest freshwater bodies in the world, located in the United States and Canada. Lake Huron, Lake Ontario, Lake Michigan, Lake Erie, and Lake Superior make up the Great Lakes.
type of surfboard used for riding big waves.
environment where an organism lives throughout the year or for shorter periods of time.
to ride a surfboard facing backward, with the surfer's heels over the front of the board.
to ride a surfboard with all ten toes curled around the front of the board.
tropical storm with wind speeds of at least 119 kilometers (74 miles) per hour. Hurricanes are the same thing as typhoons, but usually located in the Atlantic Ocean region.
(2008) storm causing damage to Caribbean nations, Louisiana, and Texas.
the study of water in motion.
tropical ecosystem filled with trees and underbrush.
type of seaweed.
underwater habitat filled with tall seaweeds known as kelp.
having no access to an ocean or sea.
surfboard with substantial planing surface, about 3 meters (9 feet) long.
type of tree with reddish-brown wood.
a skillful movement.
inorganic material that has a characteristic chemical composition and specific crystal structure.
landmass that forms as tectonic plates interact with each other.
a material that humans take from the natural environment to survive, to satisfy their needs, or to trade with others.
the front end of a surfboard.
to darken or partially block.
large body of salt water that covers most of the Earth.
person who studies the ocean.
a long, deep depression in the ocean floor.
fossil fuel formed from the remains of marine plants and animals. Also known as petroleum or crude oil.
large ship used for transporting petroleum.
extremely long, heavy surfboard used by Hawaiian royalty.
international sports competition divided into summer and winter games held every four years.
facility where paper is manufactured from pulp or wood.
fossil fuel formed from the remains of ancient organisms. Also called crude oil.
series of pipes used to transport liquids or gases over long distances.
chemical material that can be easily shaped when heated to a high temperature.
area where underwater rocks or land jutting out from shore forces waves to break.
introduction of harmful materials into the environment.
island group in the Pacific Ocean between New Zealand, Hawaii, and Easter Island.
place on a body of water where ships can tie up or dock and load and unload cargo.
animal that hunts other animals for food.
animal that is hunted and eaten by other animals.
pure or unpolluted.
areas of fast-flowing water in a river or stream that is making a slight descent.
to lower or lessen.
a ridge of rocks, coral, or sand rising from the ocean floor all the way to or near the ocean's surface.
area where a coral or rocky reef force waves to break.
type of wave that breaks in a stable pattern. Also called a spilling wave.
overflow of fluid from a farm or industrial factory.
underwater or low-lying mound of sand formed by tides, waves, or currents.
the floor of the ocean.
marine mammal with flippers and a sleek coat.
one of several endangered species of marine reptile native to tropical and subtropical oceans.
marine algae. Seaweed can be composed of brown, green, or red algae, as well as "blue-green algae," which is actually bacteria.
liquid and solid waste material from homes and businesses.
beach, or where a body of water meets land.
type of surfboard about 2 meters (6 feet) long.
art and sport of riding a short piece of wood or plastic mounted on four wheels.
slant, either upward or downward, from a straight or flat path.
precipitation made of ice crystals.
dramatic and impressive.
type of wave that does not move or lose strength.
political unit in a nation, such as the United States, Mexico, or Australia.
extreme incline or decline.
severe weather indicating a disturbed state of the atmosphere resulting from uplifted air.
underwater valley formed by eroding streams of muddy water through which sediment ultimately reaches and spreads across the flat abyssal plains of the ocean floor.
waves as they break on the shore or reef.
underwater obstacle that causes waves to break, causing waves that can be surfed before eventually crashing.
the sport of riding down a breaking wave on a board.
point in the ocean at which waves begin to break.
wax applied to surfboards to help the surfer's feet stick to the surface.
surf zone forecast
document produced by the National Weather Service that predicts the wave action of specific areas.
type of wave that does not break until it reaches the shore or cliff.
stable, crestless wind wave formed far out at sea.
flat, usually plastic devices attached to a swimmer's feet to enhance movement. Also called flippers.
to use a surfboard to ride the waves created behind oil tankers.
tidal wave. Tide flowing upstream against the current of a river, forming a wave of water.
study of the shape of the surface features of an area.
body, excluding head and limbs. Also called a trunk.
person who travels for pleasure.
type of surfing where the surfer is transported beyond the surf line by a boat or Jet Ski.
the grip between an object and the surface on which it moves.
journey, especially across difficult terrain.
very large or important.
a gently sloping depression in the ocean floor.
tropical storm with wind speeds of at least 74 miles (119 kilometers) per hour. Typhoons are the same thing as hurricanes, but usually located in the Pacific or Indian Ocean region.
track of waves left behind boats or other large objects moving through water.
to use a surfboard to ride the waves created behind boats or other large objects in the water.
transportation vessel, such as a boat, for a body of water.
moving swell on the surface of water.
state of the atmosphere, including temperature, atmospheric pressure, wind, humidity, precipitation, and cloudiness.
tight-fitting outfit worn by divers and swimmers to retain body heat in cold water.
movement of air (from a high pressure zone to a low pressure zone) caused by the uneven heating of the Earth by the sun.
movement of surface water caused by the motion of air.
a fall caused by losing control while riding a surfboard.