Saturday, September 29, 2012

Estuary Meditation

Estuaries are places where rivers meet the ocean ― bays, harbors, lagoons, salt marshes, tidal inlets, barrier islands, and sounds.

The estuary is a transition ecosystem between rivers and ocean ― a zone influenced by marine phenomena like tides, waves, and the influx of salt water and riverine phenomena like fresh water flows and sediment transport.

Conceptual Diagram of an Estuary.
Source: Louisiana Universities Marine Consortium (LUMCON)

Blue Crab
Estuaries are among the most productive micro-environments on earth with more organic matter created annually than comparably-sized forests, grasslands, or cultivated land.

Sheltered estuarine waters support thriving communities of plants and animals especially adapted for this ecosystem.

To stand at the edge of the sea, to sense the ebb and flow of the tides, to feel the breath of a mist moving over a great salt marsh, to watch the flight of shore birds that have swept up and down the surf lines of the continents for untold thousands of year, to see the running of the old eels and the young shad to the sea, is to have knowledge of things that are as nearly eternal as any earthly life can be.
Rachel Carson

Estuary of Klamath River in Redwood National Park.

The nutrient cycle, the water cycle, and the cycle of life are the primary physical and biological phenomena found in estuaries:
  • Nutrient Cycle - Many elements are recycled in estuaries providing sustenance to living organisms. The health of an estuary depends on a balance of these elements.
  • Water Cycle - Evaporation occurs in estuaries and fresh water recharges ground water reserves.
  • Cycle of Life - Estuaries provide food, shelter, and nurseries for animals. Decomposing animals provide nutrients for other organisms.

We need the tonic of wildness, to wade sometimes in marshes where the bittern and the meadow-hen lurk, and hear the booming of the snipe; to smell the whispering sedge where only some wilder and more solitary fowl builds her nest, and the mink crawls with its belly close to the ground.
Henry David Thoreau

National Estuaries Day is an annual observation in the US held on the last Saturday of September.

Saturday, September 22, 2012

Ode to Dew

Drops of water formed by the condensation of moisture in the air is dew. Dew occurs when the moisture in the air is cooled to its dew point.


Dew drops assumes the shape that minimizes the sum of its gravitational energy and its surface tension. Surface tension is expressed as force per unit length. Water has a surface tension of 0.072 N/m.
Man's life is like a drop of dew on a leaf.
The shape of a dew drop cannot be described by a closed form mathematical function. The governing differential equations do not have a closed form solution, so must be integrated numerically to trace the profile of a drop (cf. The profile of a dew drop).

A drop of dew cupped in the leaf of the common garden nasturtium.
The person who doesn't scatter the morning dew will not comb gray hairs.
- Hunter S. Thompson

The term refraction describes the deflection of light that occurs when light waves travel through a change in medium (e.g., from air to water). Water droplets refract light like a lens.
When we contemplate the whole globe as one great dewdrop, striped and dotted with continents and islands, flying through space with other stars all singing and shining together as one, the whole universe appears as an infinite storm of beauty.
- Travels in Alaska by John Muir, 1915, chapter 1, page 5.
Refraction Photograph by Markus Reugels
Photographer Markus Reugels uses the refraction of light in water to create still life images in a drop of water.


Saturday, September 15, 2012

September Equinox

The earth has two equinoxes – one in September and one in March. The September Equinox will occur next Saturday September 22 at 14:49 (or 2:49pm) Coordinated Universal Time (UTC).

What is the equinox?

September Equinox
The equinox occurs when the sun shines directly on the equator and the length of day and night is nearly equal. The twilight zone is a moving line that separates the illuminated day side and the dark night side of the earth. The equinoxes are the only times when the twilight zone is inclined 90° to the Earth's Equator.

Equinox is a Latin word meaning equal night. At the cusp of the equinox, night and day are 12 hours. The equilux is a word that describes that time when sunset and sunrise are exactly 12 hours apart.

A Reflection on Seasons

Seasons are opposite on either side of the equator. In the northern hemisphere the September equinox is known as the autumnal equinox. In the southern hemisphere it is known as the vernal or spring equinox.

Here in the North American continent, we are experiencing the approach of the autumnal equinox. It is a time of the year where we appreciate the remaining plant life, particularly delighting in autumn flowers.
Earth laughs in flowers.
Ralph Waldo Emerson
Flowers in autumn seem to grow more vibrant in color as the days and nights grow cooler - as if to defy their impending death.

At the autumnal equinox, many of us notice the waning plant life knowing their time remaining will be short. Philosopher Albert Camus noted:
Autumn is a second spring when every leaf is a flower. 
Morning Glory

Some sowers of flower seeds bury pre-soaked and razor-scored Morning Glory seeds each Spring in a sort of long-view anticipation of the short window of their bluish-purple bloom in late summer and early autumn.

The Morning Glory is one of the sublimest of flowers, perhaps because of its sudden vibrancy and fleeting display of color. Poet Walt Whitman noted:
A morning-glory at my window satisfies me more than the metaphysics of books.
Poet Matsuo Bashô (松尾芭蕉) wrote:

asagao ni
ware wa meshi kû
otoko kana
I am one
Who eats his breakfast,
Gazing at morning glories.

A Morning Glory
Many of the uncertainties we fret about have no permanence; like autumn flora they gradually pass away.

In the natural world, the autumnal equinox is a time for scattering and sowing seeds.

For humans, the autumnal equinox is a time for reflection, for renewing attentiveness, and for appreciating all that's fleeting.

Saturday, September 8, 2012

The Mountain River Sūtra

The earth presents its inhabitants with seemingly endless enrichment and, when we are most lucky, fleeting opportunity for enlightenment. In River Run Dance, I wondered about the metaphysics of water molecules flowing in a river.
Would we need to trace a water molecule to know that water flowing through a river is never the same water?
I have the same wonder about mountains. What is the beginning of a mountain? Do mountains have a beginning and an end? Yes and no.

Orogeny and Erosion

Orogeny and erosion are a mountain's yin and yang. Orogeny encompasses the events leading to the deformation of the Earth's crust because of the engagement of tectonic plates.

From plate collision, a mountain begins.

Erosion refers to soil and rock that is transported by wind or water flow to other locations.

From transporting winds and water flow, a mountain ends.

Does it matter if a mountain has a beginning and an end?

Perhaps we only need revel in the endlessness and the continuity we experience.
Revel in the endlessness, the endless repetition - the mountains forming, the rivers flowing, and the planet rotating and orbiting to change our light and to change our seasons.
An Earth Verse by poet Gary Snyder:
Earth Verse

Wide enough to keep you looking
Open enough to keep you moving
Dry enough to keep you honest
Prickly enough to make you tough
Green enough to go on living
Old enough to give you dreams

from Mountains and Rivers Without End

A Sūtra

Gary Snyder refers to his the poems in Mountains and Rivers Without End as a sūtra - a collection of words woven to embody a general truth. The literal meaning of the sūtra is a thread or a line that holds things together. The word sūtra is similar in derivation to the medical term suture.

Mr. Snyder's Mountains and Rivers Without End was inspired by a 17th century ink on paper handscroll of the same name.

Mountains and Rivers Without End
Handscroll; ink on paper
Lu Yuan, mid- to late 17th century, China

Saturday, September 1, 2012

River Run Dance

Gallatin River
If a river is the dancer, then gravity must be the choreographer.

A river's source is a lake, a spring, or a series of small streams or headwaters. All rivers flow downhill from their source. Rivers typically terminate in the ocean.
Would we need to trace a water molecule to know that water flowing through a river is never the same water?
A river's life is significantly longer than a human generation. Seen over the course of a human lifetime, a river swells or shrinks seasonally and temporally, but in the aggregate, seems steady in course and flow.

"I thought how lovely and how strange a river is. A river is a river, always there, and yet the water flowing through it is never the same water and is never still. It’s always changing and is always on the move. And over time the river itself changes too. It widens and deepens as it rubs and scours, gnaws and kneads, eats and bores its way through the land."
― Aidan Chambers, This is All: The Pillow Book of Cordelia Kenn

On a geologic time scale, a river has a dramatic life-cycle.


A youthful river has a steep gradient. It has rapid flow and has few tributaries. The steep gradient causes erosion that is deeper rather than wider.


Mature rivers have a milder gradient and slower flow. It is fed by many tributaries and has a greater volumetric flow rate. The milder gradient causes erosion that is wider rather than deeper.


An old river has a low gradient and low erosive energy. Old rivers are characterized by flood plains.

Mississippi River
Eventually, all things merge into one, and a river runs through it. 
― Norman Maclean, A River Runs Through It