LOCAL swimming
keep it safe
DISCLAIMER
The following is a short guide to swimming at Clevedon, based on KNOWLEDGE & PRACTISES of local swimmers.
DO NOT rely on it, do your own research, and decide whether or not to swim based on YOUR abilities and prevailing conditions.
Ideally, join local swimmers and seek their advice or book a session with a local open water coach.
SEA SWIMMING
Below assumes you are a competent sea swimmer and provides the barest knowledge about where/when/conditions.
Clevedon’s most popular swimming spot is the beach beside the pier:
- Dogs are not permitted here at any time. There are other dog friendly beaches locally where swimming is also possible with care; some have submerged rocks and challenging tidal flow.
- Novice swimmers – the safest area to swim is no further out than a line between the end of the rocks beneath the pier and the slipway, see diagram. Intermediate swimmers – the orange area is popular with many regular sea swimmers, it should be noted that the tidal flow gets stronger as the water gets deeper.
- Outside these two areas is only recommended for confident sea swimmers who understand the local conditions and their own abilities to cope on any given day.
- The diagram shows the easiest place to get in. Looking out to sea, there is a slight gully to the right of some submerged rocks where less obstacles make for an easier entry and exit.
- The slipway can be used for entry and exit as long as sailing boats are not in the water. Beware of holes in the concrete. Not advisable in rough conditions; breaking waves can knock you off your feet.
ALWAYS check Clevedon tide times and weather before swimming
- The safest time to swim is about 30 mins either side of high water (HW), when the tidal flow is at its most slack.
- This swimming window can be extended to around 60mins either side of HW on higher tides but WILL require swimming in faster flowing water.
- Spring tides can flow at speeds of up to about 5 knots at the end of the pier (about 6mph).
- Strong northerly winds can cause the tide to turn earlier.
- Rule of thumb: swim out against a tide, come back with the flow.
Conditions are often choppy, with wave heights varying with wind speed and direction, as well as tidal flow. The waves can be large when windy which can make exiting the water tricky. Clevedon’s esturial location doesn’t produce the kind of rollers that you might see in Cornwall.
- S & SW winds are most common. Chop increases when the ebb tide picks up due to wind-against-tide effect.
- Westerly winds blow directly onshore and can produce bigger dumping waves on the shore when strong.
- North winds are less common. Rocks by the pier protect the beach and inshore water. Choppy on flood tide, usually causes ebb to flatten off about 30 mins after HW as ebb speeds up
- Easterly, offshore winds are uncommon. The land protects the sea closer to the shore giving flatter conditions, with increased chop further out.
NOTE: the difference in how direction of wind and current is expressed:
- “A northerly wind” comes FROM the north
- “A northerly current” goes TOWARDS the north.
- There are submerged rocks covered by seaweed either side of the slipway.
- Avoid the slipway and swimming out to the buoys if CSC are sailing (see their programme below). They sail on the incoming tide and finish on the ebb.
- Jet skis occasionally launch at Clevedon. Watch for their launch while you swim; wear a bright swim hat and use a tow float.
- Swimming around the far end of the pier is not advisable unless you know what you are doing. The dangers are: fishing lines, strong tides, long distance from the shore, getting washed through the pier head
Ask yourself “Am I doing something which might cause someone to call the Coastguard?”.
- If the answer is yes, make a call, if not, just enjoy your swim. It is common to see swimmers in the bay all year, and between Ladye Bay and the pier in warmer months.
- If you do make the call, make sure you follow it up with a confirmation that you are out of the water and safe.
It might not stop the Coastguard being called, but it will help them plan how they search and what additional resources to call upon. They would always prefer to be called and it be a false alarm, than not be called and the consequences be fatal.
- Before entering water: call 01646 690909
- Call purpose: “Routine swimmers notification for Clevedon Sea swimmers”
- Swim direction: (Whatever the intended swim is) eg Clevedon Pier Area or Clevedon Pier to Ladye Bay return
- Group details: Three swimmers, red/blue/green swim hats, all with orange tow floats
- Time into water: eg 1900hrs
- Expected duration/time out: 1 hour 20:00hrs
- After exiting water: call 01646 69090
- Swim name: “Routine swimmers notification Clevedon Sea swimmers.
- All swimmers out of water.
- Time
Another option is to arrange your own EMERGENCY CONTACT
- Please don’t try and wade through the sticky mud to the sandbank that appears at low tide.
- The coastguard is usually called by someone on shore, which will tie them up unnecessarily, even if you think you know what you’re doing: know the tides, won’t get stranded when the tide comes behind you, or don’t mind getting covered in very sticky mud.
If you are NOT an experienced sea swimmer or don’t know the area then the following provides further local knowledge.
- The incoming tide flows up the estuary, the outgoing flows down parallel to the shore, so being swept out to sea is unlikely. There are no rip tides in Clevedon.
- The currents are stronger further out meaning the closer you get to the shore, the easier it is to get back to your intended exit.
- If you are caught in a tide that’s faster than you can swim, aim to swim diagonally against it towards the shore.
- Friction will usually slow the water speed where it runs beside the rocky edge whereas rocky outcrops may increase the water speed. If you find yourself being swept towards Ladye Bay, swim into shore and work your way back against the current. Beware of submerged rocks which you can spot by the way the water breaks round them.
- If it starts to feel too much, DON’T PANIC!
- Slow down, reduce exertion, let your heart rate slow and breathing settle. Feel the waves, adjust your rhythm and look for safety.
- If you need to rest, remember the RNLI advice FLOAT TO SURVIVE: float on your back, arms and legs extended in a star. If your legs sink, push your arms down behind you in the water and gently move them back and forth
Apart from Pier beach, there are several places to exit the sea if you need to. Don’t be embarrassed to get out safely and walk back. A tow float (25l size is ideal) with towel and flip-flops will save your dignity!
- the slipway (beware rough breaking waves which can knock you off)
- Green Beach beneath the bandstand
- Little Harp beach
- Top end of the lake, exit by climbing up the rocks
- Between Ladye Bay and the pier there are two exits, though difficult to spot from the sea:
- a gully up to a concrete lookout area very near Ladye Bay
- Monk Steps 500m before reaching the pier
- The pier is 310m long, don’t swim around it unless you know what you’re doing.
- Fishermen cast from the forth leg onward, on both sides and from the head.
- Strong currents towards the end could push you through the pier head into rusty supports and old fishing lines.
First up – swim at your own risk, you are responsible for yourself! For all of you who are new to swimming between Layde Bay and the pier, it is advisable to only do it if:
- You are comfortably able to swim a mile without stopping (2 miles if you are considering going both ways).
- You know you are able to stay in the water for 30-40 mins. If you’re not used to being in that long you may get cold and put yourself (and maybe others) at risk (even when temps are warmer). Double this for a two way swim.
- You are confident swimming in the sea in Clevedon, including dealing with a range of conditions – conditions can be worse out there than expected from the shore and can change en route.
- You understand the currents and necessary timings to do this relatively safely.
- You have someone with you who has done it before.
Please start with one way and do this from Layde Bay to the pier – if you do it the other way and don’t get to Layde Bay on time you will have a fight on your hands or a much longer swim than planned.
Even those who are experienced at doing this swim will sometimes decide not to go if conditions are not suitable (e.g. when it is rough). Conditions need assessing on the day – only swim if you are super comfortable with the conditions you observe (NB: when you are in the sea the waves are always bigger than what you observed from the shore – perspective makes all the difference!) – this is why it is important to be comfortable swimming in the sea in Clevedon before undertaking this swim.
It is advisable to stick in pairs or bigger groups for a bit of moral support!
There is no turning back once you set off as fighting against the current can be difficult. If you are not sure if you are ready for this, just have a swim in the bay. Discuss currents and conditions with regular swimmers and build up your confidence and knowledge safely! A healthy respect for the sea is always advised! Swim at your own risk! And enjoy!
Credit: Vicky Bell
- Seatemperature.org provides sea surface temperature (SST) from daily satellite readings by the NOAA (National Oceanic and Atmospheric Administration). These show min/max temperatures during the year ranging from 7C to 17C.
- There are a couple of buoys in the middle of the Severn placed by MagicSeaweed, which provide sea temperatures and waves heights. The temperature close to shore can be warmer than the deeper parts of the Severn, perhaps due to local weather cooling or heating the rocks and mud over which the water flows.
- The Outdoor Swimming Society provides an unscientific but funny GUIDE TO COLD WATER SWIMMING.
AIR TEMPERATURE
- We tend to focus on the sea temperature, but it’s worth remembering that the air temperature can make a huge difference to our perception of the cold. For example, a winter swim in 5C water may feel fine when the air is a sunny 10C. It’s a different game altogether when a northerly -2 is blowing on damp skin. Front crawl leaves more skin exposed to the air; breaststrokers can fare better.
- Locals swim all year round irrespective of water quality warnings without suffering ill effects; the individual needs to make their own decision however. The estuary is hyper-tidal and turbid – the brown colour is due to silt and not a sign of poor quality.
- The water quality is primarily affected by two things: water companies discharging into the sea during periods of heavy rain, secondly, agricultural run off from further up the Severn.
- Surfers Against Sewage monitor sewage spills in real time on beaches around the UK providing a smartphone app that gives alerts when events happen.
In an emergency, call 999 and ask for the coastguard.
- An RNLI lifeboat can reach Clevedon pier in about 40 minutes in an emergency.
- The coastguard coordinates rescues from land, the RNLI carry out water based rescues.
- The local RNLI have stations in both Portishead and Weston-super-Mare. Which lifeboat is deployed depends on the tide, sea conditions, and nature of the incident. On occasions, support from the “all weather” lifeboat from Barry Dock has been provided, as has the helicopter based in Wales.
Swim preparation tips to mitigate against a small incident escalating to an emergency call out.
- Check the weather, tides and conditions, and be realistic about your ability to cope.
- Conditions may look benign from the shore, but one-foot waves will be above your head when swimming.
- If in doubt, stay out! Don’t put yourself or others at risk.
Are you self-sufficient and able to cope alone, physically and mentally, if things go wrong? What are your margins – distance, temperature, mental strength? Do you know the best direction to swim in, are you able to adapt to keep yourself safe? That initial confidence, particularly when in a group, may disappear when you’re alone. Choppy conditions can mean pod members losing sight of each other in the waves.
- Tow floats allow a rest and ensure visibility by boats, jet-skis, people on shore and members of your group. But would you swim if you didn’t have it? It may feel like a safety blanket, but don’t let it override good judgment.
- Whistle – attach to your tow float, ensure it works when wet – THREE short blasts is an international distress call.
- Wetsuit – the sea is still much colder than a pool even in summer; a wetsuit will keep you warm for longer and help with buoyancy, however, you may not need one. Everyday Athlete Rach looks at what to wear for winter swimming, some of which also applies in summer.
Being self-sufficient is also about knowing how long to stay in as well as how to warm up AFTER the swim.
- Swimming with a buddy or small group means there’s potentially help at hand; support could come from a kayaker or SUP user. Swimmers can encounter cramp, fishing lines, challenging conditions or just irrational moments of anxiety and loss of confidence.
- Ideally, team members will be self-sufficient, though differences in speed and ability are inevitable.
- Agree on individual limits beforehand and decide a group strategy if things need to change – conditions may worsen, the tide may change early.
- Conversely, beware of group dynamics creating an artificially inflated confidence which might lead to a scenario that’s beyond the ability of the group.
Where an incident presents a situation that’s beyond the ability of the group, external help will be required. This could be someone waiting on shore with kayak/SUP, a passing member of the public near a lifebelt, or the Coastguard/RNLI services.
- Share your plan – if organising a longer swim outside the popular Ladye Bay/Clevedon area, the local coastguard asks that swimmers call their Ops room, stating: time getting in and out the sea, the swim location and direction plus any distinctive gear worn – colour of hats, floats etc. Ops room number is 01646 690909. A mobile phone in a waterproof pouch with the Coastguard number on speed dials is prudent.
- RYA SafeTrx app is aimed at safe boating, but “Everyday Athlete Rach” shows how to set it up to improve swimmer safety.
- Whistles that work when wet – THREE short blasts is an international distress call.
Lake swimming
Many people prefer Clevedon’s Marine Lake to the sea for various reasons: lack of currents, wider swimming window, ease of parking, better disabled access. BEFORE VISITING always check Clevedon Marine Lake’s website and Facebook page, and observe the following:
- Events such as the Clevedon Aquathlon, or club sessions from Clevedon Sailing Club (Friday evenings in the summer), can mean part or all of the lake is unavailable for public use.
- Drain downs are usually planned for the winter months when there are less visitors and bigger spring tides for refill. Draining is done in order to carry out essential maintenance such as mud removal, handrail repairs, seaweed clearing, penstock (drain hole) checking, and general debris clearing.
- SPRING tides of 12.5m or above will go over the lake wall.
- Tides over 13m will refresh the lake and completely cover the promenade.
- You will NOT be washed out to sea when the tide turns if you keep away from the sea wall. It is also not advisable to swim close to the corner by the pumphouse as the water overtops
- The sea wall can become obscured and dangerous on an overtopping tide. Also, beware of logs that may be brought in on a bigger tide.
- Storms combined with an overtopping tide can make the lake very rough. This is partly due to its shallow depth and also due to CLAPOTIS – where incoming waves bounce off the sea defense wall by the promenade, smashing into the next set, creating larger standing waves and deeper troughs
- As the diagram shows, the deepest part of the lake is near the sea wall at the wider (Southern) end near the old pumphouse.
- The lake is very shallow around the edges and at the end by the splash pool.
- Visibility is too poor in the lake to make diving safe.
- The lake is now extremely popular, particularly with swimmers, more so since lockdown. SUPs and kayak use is becoming increasingly popular. Windsurfing is not permitted.
- There are swimming and paddleboard coaching sessions at various times.
- Some clubs have MARLENS membersip such as Clevedon Canoe Club, Clevedon Sailing Club, Clevedon Coastal Rowing and PACtri, all of whom hold their own activities and sessions at various times.
- Check the Clevedon Marine Lake calendar before visiting.
- A local lab performs bathing water quality tests on lake water samples collected by MARLENS volunteers during the summer months. North Somerset Council tests the sea water only.
- Increasing visitor numbers and high average temperatures in June have meant bacteria have reached levels considered unsafe for bathing. In this instance, MARLENS raise a red flag to warn of the danger as well as adding signs around the lake and notices on their website and facebook page.
- Many locals continue to swim despite these warnings, some suggesting that the standard is set too high. Each individual needs to make the decision that is correct for them.
- The lake temperature increases more quickly than the sea in the warmer months, sometimes reaching as much as 26 degrees C.
- In the winter months, it becomes cooler than the sea, sometimes almost freezing whereas the sea only drops to about 4 degrees C.
- This difference is because the lake is a large body of trapped water, affected by the ambient (air) temperature. A week of very cold northerly winds (e.g. the beast from the East) blowing across the lake causes the temperature to drop very quickly.
- Overtopping spring tides can then rebalance the two temperatures depending on the tide height and the volume of water that enters.
Swimming with a disability
A couple of swimmers have kindly provided the following views about Clevedon marine lake.
I can’t recommend Clevedon Lake for all disabilities as I’m willing to take some risks. I would say Clevedon Lake is perhaps for people with mild disability because it can be slippery and takes some effort to get in and out. For greater disability, more accessible and safer places to swim are Portishead lido and Vobster Quay
- Don’t go alone, take a buddy in case you slip or get cramp and can’t get out alone.
- Always take a mobile phone so it’s easy to call someone.
- Take a hat and sun cream down if it’s hot as you don’t want to get too hot or burnt in the water.
- Take a buoyancy aid to help you stay afloat and reduce fatiguing. I always take my swimming noodle.
- If you can’t swim, never go where you cannot stand up or where there are tides.
- I would definitely recommend the lake to other disabled swimmers.
- There is great parking nearby next to the Salthouse Pub with plenty of disabled spaces and the toilets near the end of the lake are ok to use and get changed in. Just remember the 20p as they don’t accept Radar keys. Also, the door into the toilet is quite narrow so anyone with a wide wheelchair might struggle as mine is quite narrow and I only just fit.
- Getting down to the lake side couldn’t be easier as there is plenty of ramped access. There is no hoist but I wouldn’t expect there to be but I had someone with me who could help me get back from the lakeside into my wheelchair.
- If I position my chair against the steps nearest the see wall I’d be able to use the frame of the steps to help climb up and into my chair.
- If using a wheelchair I’d also suggest getting a bike lock and securing your chair to the steps if you are there on your own. I’m sure no-one would wander off with your chair but it’s not worth the risk if that is your only way of getting about.
- A small, padded yoga mat might also be helpful to sit on when shuffling into the lake as the floor is quite bobbly and uneven and could break the skin.
- Once in the water, it’s lovely! It’s quite shallow near the promenade at either end so if you can’t feel your feet I’d recommend some verruca socks or waterproof slip on shoes just to protect your feet.
- Also, be aware that it’s 250m long so don’t feel you have to swim the whole length of the lake as you have to get back and if like me you are only using your arms it can be quite a slog if there is a headwind
Tidal science
This section provides an introduction to the sea, the tides, what causes them and how air pressure and wind affects sea conditions.
THE SEA
- Tides generally rise and fall twice a day around the British coast (an exception is the Solent and Poole harbour which have double high waters due to tides going round the Isle. Weymouth Bay has double low waters due to the tide going round Portland Bill).
- TIDE TABLES show when the tide is at its highest, called HIGH WATER (HW) and lowest, called LOW WATER (LW).
- The height is mainly affected by the gravitational pull of the moon, causing the seas to bulge outward towards it. A bulge is also caused on the opposite side of the earth due to centrifugal force from its spin. The combined gravitational and centrifugal forces create an ellipse.
- As the moon moves round the earth, the bulge moves with it and we experience the two bulges as rising and falling tides twice a day.
- This is sometimes referred to as a SEMIDIURNAL tidal cycle.
- The sun affects tides also but has a smaller influence than the moon, however their combined gravitational pull affects how high and how low the tide rises and falls:
- SPRING TIDES occur on a FULL MOON and a NEW MOON. The combined gravitational pull and alignment of the sun and the moon causes a bigger tidal bulge leading to extra high and low tides. Spring tides occur all year, unrelated to the seasons. Spring tides occur roughly 36 to 48 hours after a full or new moon due to the different orbits of the sun, moon and earth. For any given location, they are always at roughly the same time of day. For example at Liverpool, the spring tides are generally around midnight and midday.
- NEAP TIDES aren’t as high or as low as spring tides because when the sun and moon are at right angles (first and 3rd quarter moon), the sun’s gravitational pull reduces the moon’s pull and they work against each other.
- The sun and moon are in alignment twice a month, one new moon and one full moon, so we get two springs and two neap tides each (lunar) month.
- A solar day is 24 hours but a lunar day is 50 minutes longer: the moon revolves around the Earth in the same direction in which the Earth spins, so it takes the Earth an extra 50 minutes to “catch up” to the moon. Therefore, it takes six hours and 12.5 minutes for a tide to go from high to low or vice versa. So, assuming HW is at midnight, low water would be about 06:12, then HW at 12:25 and the following LW at 18:37
- The height difference between HW and LW is called the TIDAL RANGE.
- The largest tidal ranges occur at the EQUINOX, when the center of the sun is directly above the equator causing the day and night to be of equal length all over the world. This occurs twice each year, around 21 March and 21 September.
- National Tidal and Sea Level Facility shows the highest & lowest predicted equinoctial tides for Avonmouth. For 2021 they are shown as 30 Mar 14.22m and 8 Oct 14.06m for Avonmouth. For Clevedon, tide tables show a full moon on 28 Mar and 2 days later on 30 Mar, HW is 08:59 at 13.7m. On 6 Oct there is a new moon, and 2 days later on 8 Oct, HW is 21:14 at a height of 13:49m.
- Tidal currents are properly called tidal streams; this is the horizontal movement of sea water as the tide rises due to the bulge caused by the moon. Water flows around land masses and up and down estuaries. You can purchase a tidal stream atlas showing the direction of tidal streams at different times of day, displayed as thick and thin arrows which represent speed. An atlas will have a page for each hour before and after high water.
- Unimpeded tidal streams flow at no more than about 2 knots. Speed will increase where a flow is restricted, perhaps pushed upwards by the shape of the sea floor, by rocks and sand banks etc. Take a look at the sea just north of Portishead Point Lighthouse and watch the “boils” as the fast current is forced upwards. At Portland Bill the water is pushed round a landmass. The famous tidal Severn Bore is created by water being squeezed through a gap and forced up the estuary.
- There are a couple of handy rules of thumb to calculate height and speed if you know the high tide TIME and HEIGHT on a particular day (see the maths):
- The Rule of Twelfths for estimating tidal heights. It assumes a six hour period from Low Water to High Water, see diagram for explanation of the rule
- The 50/90 Rule for estimating tidal flow: Initially there is no flow; this is known as slack water. At the end of the first hour, the tidal stream reaches 50% of its maximum speed, at the end of the second hour, 90%, and at the end of the third hour, 100%. At the end of the third hour, the tidal stream has reached its maximum flow. After this it slows down to 90% at the end of Hour 4, and 50% at the end of Hour 5, before reaching slack water at the end of Hour 6.
- The Bristol Channel extends as far as Sand Point, at which point it is known as the River Severn Estuary as far as Aust. The estuary is about 9 miles wide between Cardiff and Weston-super-Mare and about 2 miles wide at Aust.
- The Bristol Channel and Severn Estuary has the UK’s highest tidal range. It has the third highest tidal range in the world, beaten only by the bay of Fundy and Ungava bay, both in Canada. The tidal range on the Severn can be as much as 15m (49ft), this combined with the ‘funnel’ shape of the estuary causes the incoming tide to create a visible wave called “The Severn Bore“.
- Big spring tides will often lift rubbish and debris from the banks of the Severn, debris that has blown in or been deposited from previous high tides and weather.
- Tides over 12.6m will flood the lake and lower surrounding walkway. Tides below this height may be affected by low pressure and onshore winds and become higher than predicted
THE AIR
Atmospheric pressure affects tide heights, see attached chart:
- LOWER tides occur with good weather because the HIGH air pressure system squashes the sea down.
- HIGHER tides occur with bad weather because the low air pressure system allows the sea to rise.
- The above won’t be apparent in the sea, however the tide line will sit further up or lower down the beach at HW.
- In the lake, tides over 12.6m will go over the wall and flood the promenade. If we consider a day when the tidal height is predicted to be only 12.5m: on a normal day (1013mb) the tide would not overtop, but if the air pressure dropped to 960mb, allowing the tide to rise a further half-metre, the resultant 13m would easily overtop the lake wall and flood the walkway.
- Wind speed is measured in knots. A knot is equivalent to 1.15mph or 1.85kmp.
- The Beaufort wind force scale is another method of describing the wind effect on the sea surface. It uses a scale 0-12 to describe bands of wind speeds.
- There are lots of terms used to describe wind affect on water surface:
- Fetch is the unimpeded distance of water over which wind blown which causes waves to build; this could be the sea, estuary or large lakes.
- Wavelength is the distance between two sequential wave crests.
- Wave period is the time it takes for a wave to travel the wavelength.
- Wave frequency is the number of wave crests that pass by a fixed location in a given amount of time. When a wave travels, it causes a circular motion of energy to pass through the water – the water itself barely moves. Waves break on the beach when the water becomes too shallow for the wave to continue it’s circular motion and the top topples over, or breaks.
- Swell is best thought of as waves that have enough energy to travel well beyond the place of their origin. The main swell we experience is produced by strong wind far away, out in the Atlantic. Surfers distinguish between main and secondary
- Chop is usually produced by local winds. All of them have different heights, come from different directions and show different periods, which is the time between two wave crests.
- Windy website explains and shows local, main and secondary swell effects.
- Because of Clevedon’s esturial location, we don’t get the big rollers experienced on Cornish beaches. We get rough conditions, with smaller waves and lots of chop. As an example, Storm Ellen on 9th to 21st Aug 2020 brought wind gusts of 40 to 50Kt across inland areas and 50 to 60Kt across exposed coastal locations. However, the conditions were not as rough as were seen in other coastal areas of the UK
Tidal Compass have written a good series of articles about sea swimming and conditions, here’s an extract about wind: On a day with no incoming swell and a strong offshore wind, the likely effect is whitecaps out at sea, but calm water that’s perfect for swimming close to shore. This is because wind needs to blow over a large area of water to make waves, a phenomenon called fetch. Close inshore, where the wind has come straight off the beach, there has been no fetch so there are no waves – but as you go further out the ripples will grow into waves, which is why you will see whitecaps out at sea. Following this theory, if you were to spin the wind around so that it blows onshore, the whitecaps would come all the way to the shore and a heavy shorebreak would start crashing on the beach, despite the wind speed staying the same. This emphasises how wind direction is sometimes more important than speed.
Below shows the recent storms on 13th March 2021. It shows the very rough and choppy conditions we experience but not the big waves on more exposed coasts. The video also demonstrate “clapotis”, where an incoming waves bounces back from a surface to hit an incoming tide and create a bigger wave as a result. (credit: Sophia Wollschlager)