Tuesday, July 19, 2016

LOW LOW Tide July 2016

With the Moons help you can have those days when the tide is Higher than normal

These logs get pushed higher on the beach with storms and higher than normal tides.

You also get lower than normal tides.

10-11 foot tides are every day stuff here.

but a few days a year get get LOW LOW tides.

Watch your step, that lettuce grass is slippery.

We heard on the news that some Naturalest from the Seattle Aquarium would be on hand around the area beaches during this extra low tide to help identify the sea life around the rocks.

Not your every day tour around the rocks.

Mottled Anemone

Purple Sea Star


Turkish Towel

and it feels like a Turkish towel

The green is Sea Lettuce, watch your step!

Sugar Kelp

Desn't take long for the tide to start rising again.

Easy Pickings for the shore birds.

Acorn Barnicles

This Jumbo Squid got caught in the rocks, tide pools,  as the water was receding.

Just throwing a dart but im guessing the tidal change was 16 feet.

lots of moon jelly's

The further you look back through the crevices the more sea stars are revealed

Keyhole Limpet

It has been very difficult to see any sea stars around the last two years due to sea star associated dinsovirus.
The Sea Stars are starting to rebound as more are being sighted throughout the coastal regions.
This article is from a year ago but it details the event:
Hoping a balance is returning.
LOW LOW Tide July 2016

When your navigating on any vessel in any water on earth you are using a chart to determine the water depth along your route. Whether you are using paper or electronic charts the little numbers that dot the chart are either in feet or fathoms. Where the water is very deep as in the PNW, the charts usually use fathoms. Where the depth is relatively shallow as along the Gulf of Mexico coast, the depths are marked in feet. In both cases the depth that dots all charts is the "mean low water depth". This means that the average low water depths over the course of a year are recorded and the mean average of all those readings are part of the chart data mariners use to safely navigate.

In a nutshell, a nearby massive body (like the Moon or the Sun) pulls on the Earth’s center due to its gravity. But the portion of the Earth that’s closest to that massive body gets pulled with a slightly greater force, while the portion that’s farthest gets pulled with a slightly smaller force. This differential force, known as a tidal force, causes objects to be stretched out, and causes our oceans to bulge at the points nearest and farthest from the Moon, where the tidal forces are greatest.
This NOAA site has a cool animated description of tides http://scijinks.jpl.nasa.gov/tides/
The extreme tides need more than just the moon, in our case the Sun and Moon working together at certain times of the years help creat the extremes, and just the reverse happens to create really small differential tides called neap tides

Spring Tides
When the moon is full or new, the gravitational pull of the moon and sun are combined. At these times, the high tides are very high and the low tides are very low. This is known as a spring high tide. Spring tides are especially strong tides (they do not have anything to do with the season Spring). They occur when the Earth, the Sun, and the Moon are in a line. The gravitational forces of the Moon and the Sun both contribute to the tides. Spring tides occur during the full moon and the new moon.

Neap Tides
During the moon's quarter phases the sun and moon work at right angles, causing the bulges to cancel each other. The result is a smaller difference between high and low tides and is known as a neap tide. Neap tides are especially weak tides. They occur when the gravitational forces of the Moon and the Sun are perpendicular to one another (with respect to the Earth). Neap tides occur during quarter moons.
The Proxigean Spring Tide is a rare, unusually high tide (and Low tide). This very high tide occurs when the moon is both unusually close to the Earth (at its closest perigee, called the proxigee) and in the New Moon phase (when the Moon is between the Sun and the Earth). The proxigean spring tide occurs at most once every 1.5 years.
The above is from http://home.hiwaay.net/~krcool/Astro/moon/moontides/

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