Key distinctive characteristics between bottom tides and wind-induced waves

Now, as the lengthy time interval surge is moving toward the beaches of Sydney (which is a rather unusual occurrence for surfing fans), it is a suitable time to look into the key distinctive characteristics between the bottom and wind-induced waves.

Resemblance and Dissimilarity

What’s the catch

Gentle waves

From the science viewpoint, bottom waves and wind-induced waves are just similar.

The force of the wind is carried into the sea when the winds spread over the body of water.

Generally, the more forceful the blow, the more continuous the durability and the bigger the spacing between the windward coast and the wind line (also named impact area – the outstretch of water which is influenced by the winds’ blowing), the greater force is brought into the sea and the heavier wave conditions will develop.

What counts most is the spacing between the bottom waves’ generator and the line where the surf heads toward the beach by means of breakers.

When the force of the surf gathers strength and builds up its energy within the time and space into a well-formed bottom waves’ succession, the strength of every tide advances.

It is worth to keep in mind that this concerted action may also cause the outstretch of the distance between wind-induced wave sets one from the other, producing instable wave conditions.

These events are responsible for the wind-induced wave time interval that finally comes into being.

How It Impacts the Riders

The time interval of tides is chiefly the amount of time between the tides in succession.

If the weather report prognoses of 15-sec time interval, it envisages that when the bottom breakers crash into a beach, you will see the top of every crest running over with the same time interval of just 15 sec.

In reference to the surfing sport, the frequency rhythm likens to the force. And this force is a crucial aspect of dissimilarity between the bottom waves and wind-induced waves.

Have a look at two patterns:

  • Pattern № 1: specific North-Easter wind-induced waves are developed as a consequence of high-pressure settings nearby the coast-line. The blow can be forceful but not that lasing and the spacing between the windward coast and the wind line is quite little.

Consequence: Although the aftereffect may cause some high-rise waves, the time interval will most likely be a rather short, about 8-second lapse, and the tides may be lower / calmer / softer (or, as we name them, regular bottom waves ), based on the bottom configuration individualities where the bottom breaker splashes down.

In this pattern, tides may also be affected by the blow, with regard to the proximity of the wind generator to the bottom breakers rolling spot.


  • Pattern № 2: remember the tropical storm that has developed a lengthy time interval it coming to the Sydney coastline right as we speak (I should snap it up and rush in for my riding session). Paul Billingham, the main expert on synoptic meteorology, explanations on this storm features:

A lengthy time-interval surf has settled as an outcome of the Tropical Cyclone – the storm of force III was generated far away at So Pac South Pacific.

While the Cyclone hits 2500 sea miles away from the Australian East Shorefront, this storm sets up a few days of average-scale and occasionally high-scale wind-induced waves throughout the whole Eastern Coastline.

Even with the windspeed of the wind-driven waves outspread not exceeding 20-35 nautical knots, its slow-paced southward progression prolongs the duration of the wave formation activity – consequently contributing to the growing surf intensity throughout the same region of South-West Pacific.

The ultimate wave elevation mark caused by the Cyclone measured up around 25 feet and even rose to a bit more than 30 feet point the next day, followed by the gradual intensity reduction and ensuing subsidence within the next 24–36 hours.

storm in sydney

The positive aspect of this Cyclone is its prolonged, slow-paced movement throughout the South-West Pacific resulting in the long-term effect of the lengthy time-interval bottom waves.

Following the established pattern, the original jolt is reinforced by a more sizable wave surge – reaching the maximum of 4-5 feet of tides with an extensive time interval of about 15-17 seconds.

Outcome: As distinct from the smaller, slighter, low-energy waves, this east-northeast bottom surge of 15-17 sec time period can generate powerful, violent, and stormy swell (mindful of the ocean bed features that are crucial to the tides formation).

So, what are the core aspects of dissimilarity between the bottom and the wind-driven waves?

Well, we establish the reference point at a 10-sec gap. Middle to an extensive interval of the bottom waves outtops a 10-sec gap, while the short time-interval of the wind-produced waves is beneath a 10-sec gap.

One more extra differential peculiarity between the wind-induced waves and the bottom waves is its trigger, which is typically site-restrained (as in the first pattern) or generated at long range (as in the second pattern).

Does undersea bottom configuration impact your performance

Wind wave

Surf-riders may be insensitive to this notion, however, surf-bathing profoundly depends on natural sciences.

Riders rely upon a scientific basis when tinkering their paddleboards (in terms of form or components) to receive the best hydro-dynamical characteristics.

Numerous riders turn to scientific foundation regarding meteorological predictions to catch the best breaking wave.

Nonetheless, there is a neglected subject to research called bathymetry that clarifies the character of bottom tides in such a manner that provides riders with a new understanding of how coast-line and bottom topographies influence the character of the waves.

What is the bottom configuration survey

Relief of ocean

The notion of the bottom configuration survey is defined as “the exploration of ‘ground’ or ‘bottom’ of water objects such as oceans, seas, rivers, or lakes.”

The survey of bottom configuration aims to provide insight into nautical ecology, water streams, and make towns ready for tidal waves.

In the context of surf-riding, it offers more evidence on where to expect the best breaking wave.

Do the bottom features influence the nature of tide

Ocean Winds and Waves

The contour of the seabed or a river bottom makes the water streams move in various manners.

In the sea, when the wave hollow flows upon a sloping ground of undersea, the top of the wave breaks into the hollow and creates a breaking wave.

When it comes to rivers, the boundaries of waves roll in across the riverside, giving the opportunity for the waves to travel far with impeccably limitless force. In addition, rivers stand for seiche when water streams splash over the sunken rocks and grounds developing an endlessly crashing, stationary wave.

Any of these situations provides surf-riders with some original untraveled locations to discover.

Dependence of the bottom configuration and the character of waves

Hawaii Surf

Hawaii Surf

Hawaiian coastline is a famous location for surf-riders on a global scale.

Such a favorable environment springs up as a result of the native slopes of the submerged lava rocks that spread up to the very coastline.

When a wind-induced tide comes to the islands’ shores, the foreside of the breaker starts to lift with the ground and reduces its speed.

Meanwhile, the hinder side of the wind-induced tide flows on with the same pace.

Thus, the hinder of the wind-induced breaker develops extra power and the greater volume of water at the fore side keeps it up. Such progression carries on till the hinder part of the breaker rises to its maximum and splashes over the foreside.

This process guarantees Hawaiian Islands high-rise wind-induced breakers near the shoreline and some of the greatest surf experiences for the riders.

California Surf

California Surf

The surf of California provides the other type of experience as its coastline is located at the peak of the borderline between the Pac and NA tectonic plates.

A lot of researchers associate it with the frequent earth-quake activity, but it creates an amazing undersea bottom configuration.

The plentiful hollows and crests impact water behavior



The undersea hollows of California offer another type of surf that differs from those Hawaiian waves.

When a wind-induced wave travels toward a hollow, the midpoint of the breaker splashes down the hollow whereas the remainder of the wind-induced wave passes above a smooth relief.

The section of the wave that goes into the hollow drags the water onward. As the underside of the wave has submerged to flush the hollow, the top of the wave has not as much force to crash over.

The brims of the hollows create some favorable surf, but within the hollow, that body of water might not transform into a breaker till it gets the shoreline.


The undersea cliffs of the Californian coastline produce a different type of surf.

Those cliffs present the hindrance for the wind-induced waves and make them splash and fall down earlier than is generally supposed.

Moreover, cliffs drag the wind-induced waves down one by one in such a way that they break over themselves.

Due to the cliffs, some very intense whitewater is developed which makes surf-riding more tough and ruthless.

River Surf

river surf

The character of the river surf has certain distinctive features in comparison with the ocean swell.

Rivers create favorable conditions as a result of tidal motion and various marine obstacles, which makes river surf-riding unlike and unique.

Surfers travel around the globe, in particular to Europe, North America, or the Amazon, in pursuit of such a special experience.



Some other watercourses may produce seiches. That is a kind of swell that is developed as a result of underwater rock bathymetry which makes the flow go back and swirl, creating a ceaseless, standing swell.

That action may be compared to how rapids shape up but the outcome is the surf that looks like common ocean wind-induced breakers.

Surf-riders appreciate this type of swell as it reminds riding great, ocean wind-induced breakers with the advantage that they don’t calm down.

Underwater bed configuration may play a crucial role when picking up your next surfing destination.

Nowadays, surf-riders can rely on the ground maps that are in open access to make a decision whether they would prefer to surf the ocean wind-induced breakers, or they might take a shot at gliding the tide-wave or even seiches.

Without a doubt, surf-riders gain a great advantage from being familiar with the undersea bottom contour of their beloved surfing locations.

Put boards into comparison


Purchasing a paddleboard without any regard to the conditions you will be riding it in and without due care for the board’s target purpose, there is a high chance for dire consequences.

Always pick up the most suitable paddleboard for your circumstances. Various paddleboard configurations behave differently on the diverse kinds of wind-induced tides.

There is a tiny, though important, subtle aspect: choosing your paddleboard is very individual. What fits one surf-rider may not be fit for the other; one man’s trash is another man’s treasure. 

What paddleboard will serve best for a particular kind of tides

Stand on a Paddleboard

There are three different kinds of tides – rock, shore, and reef swell.

Though, not every rock, shore, and reef swell is developed in the same way. As one rock swell may have gentler, smoother, softer, running bottom breakers, others may be great and violent.

For this very reason, surfboards are built to be aligned with the type of a wind-induced breaker (never forgetting specific surfing techniques), and that is why a single surfboard won’t fit all the kinds of rock bottom breakers.

It is our principal aim to put the available diversification of paddleboards in order so that you will be able to pick up the most suitable board.

There are several main designs of the boards categorized according to the type of a wind-induced tide:

  • Low Surf/Summer Lovin’ Paddleboards: Nine times out of tens we use this universal surf equipment for low-rise or mid-rise tides with regular to favorable weather states.
  • Weak Surf Grovellers: Paddleboards designed for the smallest and lowest wind-induced waves
  • High Surf/Hard-hitting Paddleboards: The kind of surf kit you rely on when the wind-induced waves are forceful and/or running high.
  • Long, Medium-length, Retro-style Paddleboards: Balks, stumps, hulks, you may call it…provided that it is lengthy and movable.
  • Refined Surfing Gear: Masterpieces: the professional workmanship put into these designs with the help of gum and foam plastic is a distinguishing characteristic of this board.
  • Another Water Gliding Devices: watercrafts, flippers, and many others. Everything that serves to add to your surfing experiments.

What is surf time interval and how it impacts riders

surf time interval

So what is the time interval? The time interval of wind-induced breakers is chiefly the amount of time between the breakers in succession.

If the weather report prognoses the surf of 15-sec time interval, it envisages that when the wind-induced tides crash into a beach, you will see the top of every crest running over with the same time interval of just 15 sec.

Remember, the greater the time interval, normally, the lengthier the time lapse between the succession of  wind-induced tides.

In reference to the surfing sport, the frequency rhythm likens to the force. The more intense the frequency rhythm, the more force is rendered into each breaker.

You have probably heard sec riders speaking about the forceful bottom breakers of 16, 19, even 21 sec time intervals of the surf washing over. And the other way round, some other locations are fortunate to have the bottom breakers with a usual 13 sec and 8-10 sec time interval.

Keeping in mind the essence of the time interval rule, let’s get back to the subject of paddleboards.

As we have already cleared, the more intense frequency rhythm possesses more force, a bottom breaker of a certain magnitude will get more ‘jolt’ as compared to a weaker frequency rhythm.

That would mean that a rider will require not as much bulk and oaring capacity in a paddleboard he/she might use to ride the heavy  bottom breakers in Indo (with a great time interval) as opposed to the heavy wind-induced breakers in Aussie (with a moderate time interval).

I trust this piece was useful.



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