Sometimes, the wind and the waves whip the ocean into a lather. And that word—lather—is a pretty accurate description of sea foam. Sea foam is made of dissolved organic matter, a substance that is so important in the world ocean that it gets its own acronym, DOM. DOM consists primarily of the broken-down bodies of phytoplankton, including microalgae and bacteria. Algal blooms, when they start to die off, create lots of DOM. In sea foam, the DOM acts like soap, creating small bubbles that float on the water.

Dissolved organic matter is full of proteins and lipids (plus lots of carbon, which we’ll get to later). The DOM molecules can act as surfactants, similar to soap and other detergents. The molecules have a hydrophilic end that sticks to water and repels oil, and a hydrophobic end that sticks to oil and repels water. The DOM decreases water’s surface tension and promotes the creation of bubbles as the water is stirred by wind and waves.

Big storms can create huge amounts of sea foam. In 2007, the area north of Sydney, Australia was dubbed the Cappuccino Coast, as foam engulfed 30 miles of shoreline. All this foam can obscure things like rocks and sea snakes, so foam frolickers should frolic with caution.

The best part about sea foam, in my opinion, is not these big foam events, but the fact that sea foam calls attention to dissolved organic matter. We rarely see it (it is dissolved, after all), and we rarely think about it, but DOM plays a massively important role on Earth. It is a key part of the marine food web, though it is hard to eat, because the particles are so tiny. Bacteria are some of the few organisms can eat DOM.

Also, the DOM in the ocean is one of Earth’s largest carbon reservoirs. DOM is produced in the upper ocean, where the phytoplankton and zooplankton live—DOM is made of the spilled contents of their bodies and their cells. The DOM that is not consumed at the surface gradually drifts downward in the water column; it can be found in the deepest parts of the ocean, albeit at lower concentrations than at the surface. As we continue to pump carbon dioxide into the air, some of this carbon ends up as DOM, and it travels slowly throughout the ocean. Next time you see sea foam, think of the dissolved particles of organic matter and the important role they play in the ocean.

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The Great Wave off Kanagawa is often mistakenly associated with the Tsunami.

"If a tree falls in a forest and no one is around to hear it, does it make a sound?"

The philosopher George Berkeley posed this philosophical question and a quick internet search found a somewhat scientific answer in an 1894 issue of Scientific American. There they wrote: "Sound is vibration, transmitted to our senses through the mechanism of the ear, and recognized as sound only at our nerve centers. The falling of the tree or any other disturbance will produce vibration of the air. If there be no ears to hear, there will be no sound."

Maybe sometimes vibrations are heard much later, only when the right person is listening.

On January 26, 1700, at about 9:00 p.m. Pacific Standard Time one of the largest earthquakes ever to strike the Pacific Northwest rumbled across the Cascadia Subduction Zone. This massive earthquake sent a giant 33 foot high tsunami crashing onto shore, inundating the quiet coastline. While there is no written account describing the earthquake, tsunami or consequential damage, the devastation was enormous.

So wait. If there was no written record, how can we know the exact time and date when the tsunami struck? How can we know how big it was or what kind of damage it did? It took some digging and an impressive bit of scientific detective work by geologist Brian Atwater. First scientists discovered an unusual layer of sand in a marsh area that left a clue that a wave had struck, taken sand from offshore and brought it far inland. The scientists were able to date this thin sand deposit to around 1700, plus or minus 25 to 50 years. Then through tree-ring dating they were able to narrow that down to within five or ten years. Further study of tree roots narrowed it down even further to winter, 1700. Then investigators went to Japan and checked for evidence of a tsunami during that time. They looked for one which did not have a known earthquake associated with it. These were known as “orphan tsunami." There, in the records from 1700, was a tsunami the struck Japan, a wave that had the right pattern, right size, and was generated at the same place, the Cascadia Subduction Zone all the way on the other side of the Pacific Ocean. January 26, 1700, 9:00 p.m.

Can it happen again. Yes. Are we listening?

Watch the Scary Tsunamis television story online.

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