You look at your nautical chart and see
shark’s-teeth just inside the beach line? What do these mean and how can your
best use them to advantage in your chart navigation? Unlock the mystery of land
profile chart symbol secrets to boost your skipper-skills sky-high!
Choose an anchorage, land a dinghy onto a beach, or make a passage through a
coral reef or chain of islands. All of these require a keen sense of land
profile identification. Use these illustrations and descriptions to help you
make the best sailing navigation choices when approaching land…
Notice the solid black line inside the yellow circle. This shows the high tide
mark of a flat beach area. In a pinch, if you had to land a dinghy along a
barren coast, look for these areas first. Notice on the north and south side of
the landmass, rocks (shown as "asterisk" or "plus-sign"
symbols) lurk just beneath the waves.
Keep clear of green tinting. This tongue shows a mud flat, but green areas can
also signal sand bars, coral heads, oyster beds, or other dangerous bottom
characters. Use extra caution when navigating in areas where you see gaps
between green tinted blobs. These could indicate rip currents or breakers.
The underlined numbers in parentheses tell you how much rock you will see
above the water at the charted depth datum. On this chart, depths are
shown at low tide. This illustration shows rocks that will poke up 2 feet (2)
or 1 foot (1) above the water at low tide.
Check out the squiggly boundary that chart makers have drawn around this
dangerous shoal. This means that this shoal covers and uncovers with the tide.
At high tide, it will be covered, or become invisible. At low tide, it will
uncover, or become visible.
Look at the small smooth circles inside the yellow circle. These are
islets–or small islands. Because they are drawn with smooth lines (not
squiggly), this indicates that they are visible at all stages of the tide.
The number in parentheses tells you how much islet you will be able to see
above the water at the charted height datum. On this chart, heights are
shown at high tide. Thus, the islets in the illustration will poke up 6 feet (6)
above the water at high tide.
Look just inside the beach line at the serrated, shark-tooth symbols. These show
high cliffs. In calm weather, these can give shelter, but storms could cause
"cliff effect" winds that scream down the side of the cliff and hit
the water with gale force winds. In heavy weather, keep clear of cliff walls.
High mountains and volcanoes often have elevations written somewhere along the
contour. These mountains on Angel Island in San Francisco Bay show elevations of
200, 300, and 500 feet. You can pick up some mountain peaks on a small boat
radar from 20 nautical miles away in perfect atmospheric conditions.
Now you know chart navigation land profile secrets that will keep you and
your sailing crew safe and sound. With this nautical knowledge you can enjoy
worry and stress-free sailboat cruising–wherever in the world you choose to
"Written so clearly that navigation and seamanship
will be comprehensible to anyone."
— Dave and Jaja Martin, circumnavigators, authors,
and stars of the documentary "Ice Blink"
"It should be read by anyone contemplating
coastal cruising or blue water voyages."
— Ted Brewer, world famous yacht designer
Captain John Shares 25+ Years of Experience to Show You How
All this and much more. 326 pages tailored to short
handed sailors and crews. Easy to read and loaded with crystal clear
illustrations. Get your copy today!