Upwelling

When I talked about the Gulf of Guinea, I mentioned that it was a site of coastal upwelling. There are different kinds of upwelling, depending on how the process occurs. Upwelling can occur off the coast or in the open ocean. Today, I’m going to give a general overview of upwelling.

Upwelling is a process in which deep, cold water is brought to the surface of the ocean. Upwelling occurs when wind pushes the surface water away, allowing the deeper water to rise to the surface. This cold water is typically full of nutrients that are vital for seaweed and plankton growth, creating areas of high productivity.

In this nutrient-rich water, seaweed and plankton population increases drastically, which sets off a chain reaction. The large amount of seaweed attracts herbivorous fish, and the large amount of plankton attracts filter feeders and small fish. Larger fish are attracted by all the small fish. Sharks, dolphins, and even sea birds are attracted by the large amounts of fish in the area.

Areas of upwelling are very important to both the ocean and to humans.

Upwelling provides food for all kind of fish, marine mammals, and sea birds. Think of the open ocean as a desert. It’s so vast and deep that it could be days before a dolphin or a shark can find their next meal. Areas of upwelling in the open ocean are like an oasis, especially for migratory animals who might not encounter a lot of food on their long journeys.

Coastal upwelling covers about 1% of the world’s oceans, but it provides about 50% of all our harvested fish. Some of the most successful fishing grounds occur in or around areas of upwelling. And when something happens and the upwelling stops, like in an El Niño weather event, the fishing industry takes a heavy hit, harvesting fewer and smaller fish.

Upwelling is so important that scientists and businesses are joining together to try and figure out how to create artificial upwelling using technology. So if you’re looking for a job in something groundbreaking, look into artificial upwelling! I have a feeling that it’ll be an important endeavor for years to come.

Sources and links:
https://oceanservice.noaa.gov/facts/upwelling.html ⇐ brief look into upwelling
https://www.nationalgeographic.org/encyclopedia/upwelling/ ⇐ more in-depth view of upwelling and coastal upwelling
https://oceanexplorer.noaa.gov/explorations/02quest/background/upwelling/upwelling.html

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Sylvia Earle

“Everyone should be literate about the ocean. No child should be left dry!”
–Dr. Sylvia Earle

Today, I want to introduce you to “Her Deepness,” Dr. Sylvia Earle.

In 1935, Sylvia Earle was born in New Jersey, United States. At the age of 13, she and her family moved to Clearwater, Florida on the Gulf of Mexico. Being so close to the ocean, Sylvia heard her life’s calling and soon began learning all she could about the ocean and its creatures.

Sylvia worked her way through college, laboring in college labs to help pay for her schooling. At the University of Florida, she studied oceanography and biology. She went on to study at Duke University, earning her master’s degree and eventually her PhD in phycology (the study of algae) and she has made it one of her life’s projects to catalogue all plant-life in the Gulf of Mexico.

But she didn’t stop there.

She has worked aboard more than 50 oceanic expeditions and clocked more than 7,000 hours underwater—that’s more than 291 days. In 1970, she led an all-female expedition called Tektite II, Mission 6. Sylvia and four women dived 50 feet below the surface of the ocean and lived underwater in a small structure for two weeks. When they resurfaced, Sylvia Earle became a celebrity outside of the science community, and everyone wanted her as a speaker. Since then, she has used her fame and her voice to be a leading advocate for the ocean.

In 1979, Sylvia Earle set a new record off the island of Oahu for deep sea diving. In a submersible, she traveled down to a depth of 1,250 feet. While using a special pressurized suit, she walked along the ocean floor untethered for two and a half hours. As she explored these previously unknown depths, her only connection to the vessel was a communication line; nothing connected her to the world above. Her record still stands today.

Sylvia Earle started two engineering companies, Deep Sea Engineering and Deep Sea Technologies, which design undersea vehicles to help scientists explore the deep reaches of the ocean. She served as the first female Chief Scientist at the National Oceanic and Atmospheric Administration (NOAA). She is also the founder of Mission Blue, an organization that is dedicated to protecting the world’s oceans.

Mission Blue’s mission is to help establish “Hope Spots” around the world. Hope Spots are areas that are deemed vital to the health of the ocean by providing essential services, areas like coral reefs and seagrass beds. Mission Blue sends out researchers to explore new areas and to gather data that proves the locations’ importance to the ocean, and thereby to us. With the data, Mission Blue tries to convince governments to establish these Hope Spots, or marine protected areas.

Dr. Sylvia Earle is truly an inspiration, a woman I strive to become. I highly recommend looking into her life’s story, at least her career. She has published some books over the years that I would love to read, including her 1979 deep sea adventure! She’s also one of the speakers in the videos on NeMO-Net, the coral-identifying game created by NASA.
Sources:
https://achievement.org/achiever/sylvia-earle/ ⇐very in-depth article into her life and research
https://www.nationalgeographic.org/article/real-world-geography-sylvia-earle/
https://www.ted.com/speakers/sylvia_earle ⇐if you want to see her TED speech
https://www.britannica.com/biography/Sylvia-Earle
https://mission-blue.org/ ⇐if you want to check out Mission Blue and Hope Spots

Law of Refraction

My husband’s late grandfather was a fascinating man and a brilliant engineer. When I first met him, he asked me if I knew about Snell’s law. At the time, I was still in college and hadn’t taken physics yet, but it sounded familiar. When he started to explain it to me, I recognized it as the law of refraction. I remember his eyes lighting up when I caught on. Later, I learned that it was one of the ways he judged a person, and he had deemed me worthy.

I bring up this physics term because it also relates to water.

The easiest way to explain Snell’s law is with a physical example.

Take a smooth, clear glass and fill it full of water. The glass or cup can’t have any ridges or funky shapes in the glass, or the demonstration might not turn out right. A pub-style pint glass works well. Next, find a straw or a pencil—I recommend an eco-friendly steel or biodegradable paper straw—and put it in the water. Now, spend some time looking at the glass from different angles. Look from above and at eye level with the water line, and move the straw around.

What you should see is that the straw doesn’t appear perfectly straight. Sometimes the submerged half of the straw seems slightly thicker. Sometimes the two ends don’t line up, and there may be a slight bend in the straw that isn’t actually there. From above the end of the straw might look a little curved to one side.

The law of refraction governs how light bends or refracts as it passes from one medium to another, like from the air to the water. This law explains why things are not always where they appear to be in the water as seen from the air.

Luckily for us, we have a straight forward equation we can use figure out the refracted angle, though you may need to do some more independent reading to understand why it works. Other creatures don’t have mathematical formulas to help them, though.

For example, an osprey flying over a body of water will have to learn how to accurately find its prey underwater or it will starve. From the air, a fish may appear to be in one spot but may actually be a few feet to the right. If the osprey misjudges where the fish is the first time and doesn’t catch it, then its chances of getting a fish the second time are greatly reduced because it lost the element of surprise. Birds of prey must learn to adjust to this optical illusion, a failed attempt at catching prey is a waste of energy.

Another example is the Australian archer fish, a fish that has developed the ability to spit jets of water at bugs on overhanging tree branches. Archer fish learn to do this because during the drought season, their normal food supply may become scarce, so they spit at bugs to try and knock them into the water to eat.

The same distortion exists for the archer fish below as it does for birds from above. The bug that the archer fish wants to knock off its branch may actually be three inches to the left instead of straight above the fish. So, through trial and error, archer fish learn to calculate where the bugs are above the water.

At the aquarium I volunteer at, one of my favorite activities is talking to guests about the archer fish’s ability to spit water at bugs on overhanging branches. Occasionally, we’re allowed to demonstrate this by getting a live cricket on a stick that we extend over the exhibit. Very quickly, little jets of water are arching out of the water as the fish try to knock the cricket into the water.

The fish that successfully hits the cricket isn’t always the one to eat the cricket. In fact, sometimes the pig-nose turtle in the tank gets the cricket. And sometimes, the volunteer (reads as: me) doing the demonstration gets spit in the face by the archer fish. But who can get mad at that? It actually made my day!

Sources:
https://www.physicsclassroom.com/class/refrn/Lesson-2/Snell-s-Law
https://www.math.ubc.ca/~cass/courses/m309-01a/chu/Fundamentals/snell.htm
https://www.britannica.com/science/Snells-law