Sea Kayaking Navigation Class

Sea Kayak Navigation
Slide Presentation
More Tide Definitions
APHELION
- POINT IN THE ORBIT ON THE EARTH ( OR OTHER PLANET) FARTHEST FROM THE SUNCHART DATUM
- SINCE 1980 CHART DATUM “MEAN LOWER LOW WATER “ TELLS SOUNDING IN WHAT?COMPASS ERROR
- ANGULAR DIFFERENCE BETWEEN A COMPASS DIRECTION AND THE CORROSPONDING TRUE DIRECTION. COMPASS ERROR COMBINES THE EFFECTS OF DEVIATION AND VARIRTION
DECIBARD
- THE PRACTICAL UNIT FOR PRESSURE IN THE OCEAN EQUAL TO 10 CENTIBARS, AND IS THE APPROXIMATE PRESSURE PRODUCED BY EACH METER OF OVERLYING WATER.
EARTH TIDE
- PERIODIC MOVEMENT OF THE EARTH’S CRUST CAUSED BY GRAVITATIONAL INTERACTION BETWEEN SUN-EARTH-MOON.
GULDER
- LOCAL NAME GIVEN TO THE DOUBLE LOW WATER OCCURING ON THE SOUTH COAST OF ENGLAND.
LOG LINE
- A GRADUATED LINE USED TO MEASURE THE SPEED OF A VESSAL THROUGH THE WATER OR TO MEASURE THE VELOCITY OF THE CURRENT FROM A VESSEL AT ANCHOR
LONG SHORE CURRENT
- A CURRENT PARALLENING THE SHORE LARGELY WITHIN THE SHORE LINE. IT IS CAUSED BY THE EXCESS WATER BROUGHT TO THE ZONE BY THE SMALL NET MASS TRANSPORT OF WIND WAVES. LONG SHORE CURRENTS FEED INTO RIP CURRENTS.
STAND OF TIDE
- AN INTERVAL AT HW OR LW WHEN THERE IS NO SENSIBLE CHANGE IN THE HEIGHT OF THE TIDE (SLACK)
TIDEWAY
- A CHANNEL THROUGH HICH A TIDAL CURRENT FLOWS.
THROUGH
- THE LOWEST POINT IN A PROPAGATING WAVE
Zo
- SYMBOL RECOMMENDED BY THE INTERNATIONAL HYDROGRAPHIC ORGANIZATION TO REPRESENT THE ELEVATION OF MEAN SEA LEVEL ABOVE CHART DATUM
| WIND | SEAS / NOTES | ||||||||
| WEATHER | |||||||||
| hi / low | |||||||||
| precip | |||||||||
| TIDES | TIME | MAX CURRENT | NAVIGATION | ||||||
| low | LEG | HEADING | DISTANCE | TIME | |||||
| high | |||||||||
| low | |||||||||
| high | |||||||||
This is a collection of thoughts and observations on route planning in relation to swell, tide, wind and weather conditions.
It is hoped that this document will serve to point out some of the many considerations when planning or executing a journey in kayaks on the ocean.
On Land. Planning.
Study the chart, tides and weather for potential dangers.
- Shallow areas that will cause waves to steepen and break.
- Areas of maximum tidal flow i.e. Channels, Headlands etc.
- No landing zones.
- Obstructions and shallow areas that may further increase tide flow.
- Wind against tide.
- Offshore winds.
- Blocked or limited access to safe areas due to lack of water at low tide.
- How strong does the wind need to be in order to become a safety issue?
- From which direction is the wind most dangerous?
- Lightning strike.
- Shipping lanes, harbor entrances and ferry landing as potential hazards.
- Direction of swell.
Study the chart, tides and weather for potential safe areas.
- The opposite of all of the above.
- Places to get on / off the water safely.
- Off shore reefs or islands protecting the shore line.
- Places to hide from wind and swell such as behind islands and in sheltered bays. Remember swell will curve or refract around objects. You may not find shelter where you expect.
- Places where eddies may form in tidal streams (will the change in current direction increase wind against tide effect?).
- Places bigger boats cannot go i.e. outside of shipping lanes and in the shallows.
When will the danger areas be at their most dangerous and the safe areas their safest? When is maximum tide current? Will the waves break most destructively at low tide when the water is shallowest or high tide when the outer protecting reef is absorbing less energy? Will the wind increase or decrease? Will the wind change direction more off shore or more directly against the tide?
Do you know what the conditions will be like? Can you observe the conditions from land before you commit to the water? Is there a better course in relation to swell and wind? Can you and your party cope with the conditions and the possible changes in those conditions? Can you and your party get out of what you get into?
Before getting on the water. Try to be as clear as possible about all the above. Come up with a clear plan and contingencies. Confirm the plan and contingencies to yourself, your party and someone on land who is looking out for you. Make sure you all understand the plan and are prepared for the consequences.
On The Water.
Know what you are expecting. Compare this to what is happening. Is it easier or harder than expected? What is your cut off point if it gets too tough? Is your cut off point an increase in conditions or a point of no return?
Do
- Take everything seriously.
- Limit your exposure to danger areas by passing through them quickly and efficiently.
- Use safe areas to rest and prepare for the next exposed area.
- Understand the effect of swell and wind on your ability. In to the wind is sometimes easiest and safest.
- Use sheltered areas to rest, feed, drink, check equipment etc. before tackling an exposed crossing or area of coast with no landing zones.
- When in close hide behind rocks or reefs while turning to line up the kayak for a straight run out through breaking waves.
- Make sure you and your group has adequate energy reserves. "Limit of adequate reserve."
- Once a decision is made be positive carrying out your decision. Constantly monitor the situation to check that your decision was correct and adjust as necessary.
- Evaluate and learn from mistakes.
- Train hard play easy.
Rock hopping
Make it a habit to watch out to sea all the time and use all the signs to assess what is coming at you.
Learn to hold your position in wind and swell near rocks this will allow you to stay in line with the safe channel while waiting for the right wave.
Move in straight lines where possible.
Turn using your momentum or in safe areas.
If the wave isn’t white, it won’t push you side ways (much).
When surfing over reefs start close to the reef and let the wave carry you over. If you start to far away the wave will (a.) broach you, then capsize you, then drag you over the reef (b.) drop you off the back of the wave to wait for the next wave while sitting on the reef. Both are bad.
The area behind a reef may appear turbulent but if it is deep water and not too close to the next rock or reef it may be useful as a safe area.
If in doubt watch an area for more than one or two waves. Waves frequently double in size within minutes, don’t get caught out.
Long exposed shore lines or crossings
Don’t attempt anything you don’t have the reserves do twice if necessary.
Consider taking a sea anchor and know how to use it to provide a mobile safety area.
Choose the optimum course for the wind and swell direction. Shortest is not always fastest.
Keep the group together it is easier to stay together than get back together.
Ensure you can reverse the route or get out if necessary. Where is the point of no return?
Maintain your average, stops and starts slow you down more than you think.
Be prepared before you start.
The ocean often gives the test before the lesson. Are you ready for the test
?
stevemseakayak.com home , thanks to Steve for above info.
Navigation Links
Moon
Phase Information
Tides
World Wide
NOAA Chart
Maker
On-line
Chart Viewer
Chart
No. 1 - NOAA Publication
Compass and Navigation
Equipment
Waterproof
Charts
Royal National Lifeguard
Institution (RNLI)
Sea
Safety - The Complete Guide (from RNLI)
Ocean Navigator
Magazine
The Barefoot
Navigator
Article 1 - The
Twelfths Rule
Article 2 - Transits
Article 3 -
Cardinal Marks
Article 4 - Tidal
Diamonds
Article 5 -
Cardinal Marks - which one?
Article 6 - How
far can you see?
Article 7 -
Hazards posed by yachts
Article 8 - How long will it take?
Article 9 - Plotter
Article10 -
Beaufort Wind Scale
Article 11 - Kayaking terms translated
Article 12 - Flares
Article 13 - Direction of Flow?
Article 14 - How far up the beach?
Article 15 - Bow Wave
Article 16 - Being Prepared
Article 17 -
Flotsam and jetsam
Article
18 - Surfable?
Article 19 - Lighthouses
