The Pull of the Tides

The tide –

a grand uncanny:

water pulling back

and pushing forward,

water in transit as we transit,

and

the moon transits and

nothing is

ever

still, is it?

1.
2. The tide sucks water through the sand forming fine-branched crevasses: a genealogy of rock particles.

3.

4. Different colored grains of sand come to rest at different places according to their weight and shape: a periodic table of sand.

5.
6. Waves throw rocks into driftwood depressions; if they fit snugly, maybe they’ll be there for a fortnight or two.

7. The swish and crash of water carves driftwood into smoother and smoother forms; the wood is like tough muscles awaiting the next task.
8.

9.

10.
11. A bed of Bull-whip kelp reveals the ebb and flow of the water: an EKG of tidal heartbeats.

12. A seaweed Mobius strip turns in and around itself, like the swirling eddies of water that left it here on the beach.

13. A sheen of moisture is left behind as a wave recedes. As soon as it appears, it evaporates. It can’t be grasped. Where is it?

14.

***

Getting a little more concrete about the “Grand Uncanny”

Several times each day water is pulled back and forth by the mingling of lunar and solar gravitational forces with the earth’s rotation. Wind, weather and even the shape of the land can play a part in these complex liquid movements that we call tides.

The most common type of tidal cycles are semi-diurnal tides. These consist of two high tides of about the same height and two low tides, also about the same height, each day. Semi-diurnal tides occur on Europe’s Atlantic coast and on America’s Atlantic coast, where I first experienced the ocean as a young girl. Our family vacationed at my maternal grandparents’ home on a coastal barrier island every spring. There, I watched migrating birds, ghost crabs and coquina clams on wide, sandy beaches with the Atlantic as a backdrop. I took the regularity of the tides for granted. We planned activities around them, like walking way out to a spit of land only accessible at low tide, or going to the dock to catch Blue crabs with baited traps at high tide. If I was at the ocean it was the Atlantic, and understanding the tides was straightforward. I just needed to visualize the smooth oscillations of high and low tides on a tide chart and remember that the peaks and troughs would hit around 45 minutes later each day.

Then I moved to the West coast. Actually, I was far from the actual coast, which was a place to visit from time to time for a change of scenery. The pounding surf, beautiful blue-green water and mammoth logs littering the shores of Washington, Oregon and California took my breath away. Amid all that drama I paid no attention to the tides. Then we moved again, this time to a small island far from the Pacific ocean but surrounded by salt water thanks to its location near the end of a long strait that is so big it’s called the Salish Sea. Living here has prompted me to get to know the tides again, but I didn’t know how complex tidal cycles can be.

The tidal cycles here are called mixed semi-diurnal tides: there are two unequal low tides and two unequal high tides each day. There are higher high tides and lower high tides, and lower low tides and higher low tides. Did you get that? Apparently mixed tides are a West coast thing, occurring from Mexico to Alaska, along the Chilean coast and in some other locations. My (east coast native) partner likes to theorize about the congruence between left coast attitudes and left coast tides. I thought all tides were as regular as the semi-diurnal ones back on the east coast, but when I look at a local tide table I see irregular waves, with peaks and troughs that vary from deep to average to almost non-existent. Here’s an example: the tide chart for December 25th, 2019.

In addition to daily tidal cycles there are spring and neap tides, which occur everywhere but which, to my mind, might make predicting tides here even more challenging. Spring and neap tides are tidal changes (also called differentials) that are bigger or smaller, depending on the moon phase. At the new and full moon the earth, moon and sun line up and their gravitational pull increases, making high tides higher and low tides lower. At the quarter moons the gravitational pull is lessened, resulting in lower high tides and higher low tides. The upshot is that tide charts are essential around here, whether you’re going fishing, want an easier time getting your kayak in the water, or are looking for Geoducks.

If you read this far you know that much more can be said about that Grand Uncanny we call the tides. Maybe I’ll write again as I learn more. For now just remember: ebb and flow, ebb and flow, ebb and flow….

15. Mew gulls pick through tidal leavings along a Fidalgo Island beach on a quiet winter evening.

***

CHANGING TIDES

Tides nourish the land, and their dependable changes remind me that if life is difficult now, it will get easier…

Sunset at Lemon Creek Pier

This week’s Daily Post Weekly Photo Challenge is “Change.”  The serene view above is minutes from a  busy New York City highway. Maybe the beautiful colors were caused by pollution, but that thought was far from my mind as I sat on the beach that evening, lost in the sound of gently lapping waves and the changing hues of sunset.

A receding tide offers foraging opportunities for Willets on Captiva Island in Florida.

The ebb tide lends itself to soft focus, also on Captiva.

Just after high tide, the noise is deafening as waves crash hard onto the rocky Washington shores of Rialto Beach.  Bit by bit, centuries of changing tides have carved a dramatic seascape here.

Happily, the only buildings in the area are well out sight – it’s just rock, water, and sky as far as you can see.

Deception Pass divides two northern Washington islands. Water from the Strait of Juan de Fuca, separating Washington from Canada, is sucked in to Skagit Bay through this narrow passage, creating whirlpools and eddies.

The bridge whose shadow you see was built in the 1930’s – it’s WAY up over the pass, but if you’re not subject to vertigo you can walk across it.

On the  bridge, you can look east towards Swinomish Indian lands,

watch the incoming tide as it ripples and flows,

and gaze straight down into paisley water swirling a tidal song of change.

Just to the north, on a rock in Rosario Bay, a gull perches precariously as an incoming tide approaches gently, leaving soft herringbone patterns on the Pacific blue waters.

In the intertidal zone the tide pools are slowly filling back up, wafting kelp in open circles.

Sea anemones (Anthopleura elegantissima), packed tightly into the tide pools, have closed up shop as the tide is out, but a few are starting to reach their tentacles out into the shallow, nutrient rich water.

At Salt Creek Recreation Area on the Olympic Peninsula the tide is halfway out, exposing a dizzying variety of colorful seaweed on the rocks.

Mussel shells tangle with seaweed on the rocks at my feet. It’s getting late, but gulls, cormorants and ducks will feast here til dusk. Tidelands along the Strait of Juan de Fuca  support a complex ecosystem of plants, invertebrates, numerous species of fish and shellfish, porpoises, whales, sea otters, birds…I’m sure there are other living things I left out. People, for example!

In Seattle the ocean is a hundred miles away but the waters are still subject to tidal changes.

Looking west towards that distant ocean, the Olympic Mountains draw a ragged edge on a golden sunset as a lone pleasure boat heads north on an ebb tide.

More Weekly Photo Challenges on the topic of Change – a BIG one! – can be found here.