## Exploring the Energy Potential of Oceans with The Next Wave 1

Today for STEM Friday we are featuring The Next Wave: The Quest to Harness the Power of the Oceans (Scientists in the Field Series). Author Elizabeth Rusch introduces us to a number of scientists who are working hard to convert the mechanical energy of ocean waves into electrical energy. See a full review at our sister blog, Wrapped in Foil.

Waves are actually very complex and we are still learning about them.

How do waves form?

The waves in the ocean form due to wind blowing on the surface. The shape and size of the waves depend on the force and steadiness of the wind, and the distance over which the wind travels, called "fetch." The shape of the wave is also influenced by the depth of the water, especially as it meets the shore.

## Activity 1. Exploring Waves

Gather:

• Plastic bin
• Water
• Food coloring
• Dropper

You may use a sink or bathtub to hold the water, but because you will be blowing across the surface, a plastic bin situated on the waterproof surface of a counter or tabletop will probably be easier to maneuver around. This would be an ideal activity to try outdoors.

Fill the bin 3/4 full of water.

Ask the children if they have ever been to the ocean and seen waves. If they have not, consider showing a video (YouTube has dozens).

Brainstorm about how to form waves. If water splashes are not a problem, allow the children to free-explore their ideas about how best to produce waves. They will probably put their hands in and swirl the water.

Now reveal that waves are formed by wind blowing over the water. Have the children blow and see how the waves look different from those they produced using their hands.

Did they form in parallel lines like in the video above?

Once the children have seen waves, add a drop of food coloring to the water and have them blow waves again. How does the water move? Do all layers move the same way?

Many texts will tell you that the water in the deeper part of the ocean does not move forward as a wave passes by, but simply travels in a circle or oscillates. Proof is given when an object floating in the water simply bobs up and down, rather than moving forward.

If you look closely at the second video, however, you will see that the top layer of the water with the food coloring moves across the surface with the waves. Why?  One possible solution is that the bin is too shallow and the waves are behaving more like those at the shore, where the circular motion is disrupted. Can you think of any other reasons?

## Activity 2. Water Vortices

Older students might want to try the experiments with vortices suggested in this video by Physics Girl (has a pop-up ad):

Isn't that incredible? I can't wait until it is warm enough to try it myself.

If your children like these activities with waves, be sure to pick up The Next Wave: The Quest to Harness the Power of the Oceans (Scientists in the Field Series) . It introduces young readers to an exciting new technology that will capture the energy of waves and convert it to useful electrical energy. The book will definitely inspire young readers who want explore waves and oceans. It is also a great resource for adults who want to learn more about this relatively new area of research on a potentially renewable source of energy.

Age Range: 10 - 14 years
Series: Scientists in the Field Series
Publisher: HMH Books for Young Readers (October 14, 2014)
ISBN-10: 0544099990
ISBN-13: 978-0544099999

You might also be interested in other books we have reviewed from the Scientists in the Field series.

Disclosures:  The book was provided by the publisher for review purposes.  I am an affiliate for Amazon, and if you click through the linked titles or ads and make a purchase, I will receive a small commission at no extra charge to you. Proceeds will be used to maintain this self-hosted blog.

Come visit the STEM Friday blog each week to find more great Science, Technology, Engineering and Math books.

## Sea Turtle Science For Kids

Today we were inspired by two books about sea turtles. The first is Sea Turtle Scientist (Scientists in the Field Series) by Stephen R. Swinburne. This book for middle grade students reveals Dr. Kimberly Stewart's efforts to investigate and conserve sea turtles on the Caribbean Island of St. Kitts. See a full review of the book at our sister blog, Wrapped in Foil.

For younger readers, we found Leatherback Turtles (Reptiles) by Mandy R. Marx with consulting editor Gail Saunders-Smith PhD. This is part of a series of informational books about reptiles featuring short sentences and carefully controlled vocabulary perfect for beginning readers.

Sea turtles are pretty amazing creatures. There are currently seven recognized species:

• leatherback sea turtle
• green sea turtle
• Kemp's ridley sea turtle
• hawksbill sea turtle
• flatback sea turtle
• olive ridley sea turtle

The leatherback sea turtle is in a separate family from the other species. It is the largest turtle, and it is also unique because it lacks a hard shell. Baby loggerheads hatch out of eggs laid in the sand on beaches. The little loggerhead turtles crawl to the sea where they live for 20 to 30 years before they reach maturity. Amazingly, once they are fully grown, the females return to the same beach where they hatched out to lay their eggs.

The Kemp's ridley and olive ridley also return to the beaches where they hatched to lay eggs. These two species, however, are a little different because many, many females return to the same beaches, all at the same time. These mass landings of female sea turtles are called "arribadas."

This video shows a sea turtle arribada from Costa Rica. WARNING for little viewers:  The video does show eggs coming out of the female's body. There's also a graphic scene of vultures feeding on a dead sea turtle around the 2:20 minute mark (near the end).

Scientists are studying how sea turtles can remember the beaches where they hatched and how they know which way to swim to return. One thing they found is that sea turtles can sense the Earth's magnetic field and use it as a guide.

## Did you know that...?

Like whales and dolphins, sea turtles must return to the surface to breathe.

Ways to help sea turtles:

Light pollution is a hazard to sea turtles. Newly-hatched sea turtles use light from the stars and moon and reflections on the water to navigate to the sea. If there are bright lights from human sources around their hatching sites, the sea turtles become disoriented and head inland instead of out to sea, which is usually deadly. Efforts are being organized to cut down excessive lighting along beaches while the sea turtles are hatching.

Finally, sea turtles mistake floating plastic bags for their natural food, jellyfish, and swallow them. The bags are not digestible and can cause death. Protect sea turtles and other animals by making sure plastic bags are properly recycled, or even better, use reusable cloth bags instead.

Related activities and links to lesson plans:

Download the discussion and activities guide for Sea Turtle Scientist at Steve Swinburne's website, as well as posters, leaflets and find links to other great websites.

See Monterey Bay Aquarium's Plastic in the Water Column lesson (scroll down to see link to .pdf lesson) as well as their open sea cam where you might spot a sea turtle.

For more information about related creatures, see our previous week of ocean-themed books and activities at Growing with Science.

Why not combine your STEM lesson with some great art by creating a watercolor sea turtle? Drawing and painting animals requires the same close observation skills so useful to scientists.

Sea Turtle Scientist (Scientists in the Field Series) by Stephen R. Swinburne

Age Range: 10 - 14 years
Publisher: HMH Books for Young Readers (January 7, 2014)
ISBN-10: 0547367554
ISBN-13: 978-0547367552

Leatherback Turtles (Reptiles) by Mandy R. Marx with consulting editor Gail Saunders-Smith PhD

Publisher: Capstone Press (January 1, 2012)
ISBN-10: 1429666463
ISBN-13: 978-1429666466

Disclosures:  Sea Turtle Scientist was provided by our local library. Leatherback Turtles was provided by the publisher for review purposes.  I am an affiliate for Amazon, and if you click through the linked titles or ads and make a purchase, I will receive a small commission at no extra charge to you. Proceeds will be used to maintain this self-hosted blog.

Come visit the STEM Friday blog each week to find more great Science, Technology, Engineering and Math books.

## Sea Horses and Other Fish 1

Our family finally made it to the beach and had a lot of fun. We visited the Monterey Bay Aquarium and saw the "Secret Life of Sea Horses" exhibit. It was awesome, take a peek:

What kind of creatures are sea horses? Are they fish? They have an exterior that looks rather hard, so some people might wonder if they are crustaceans. The tiny fins and gills give it away though, sea horses are fish! If you replay the video, look for the tiny gills and fins moving.

Sea horses and their relatives, the pipefish and seadragons, are called gasterosteiform fish because they lack scales and have bony plates instead. They are poor swimmers and often rely on camouflage to hide from predators. The seadragons in particular have so many leafy flaps on their bodies they look like floating seaweed instead of animals.

Sea horses are carnivores and eat small crustaceans, such as tiny shrimp and planktonic invertebrates.

Activities:

1.Gyotaku and fish anatomy

Are you familiar with the Japanese art of gyotaku, making prints or rubbings from fish?

Traditionally, prints were made by applying paint to actual fish. Today you can also buy rubber or plastic replicas if you don't have access to whole fish. You can print on paper or cloth as you choose. This particular fish is printed on cloth.

Gyotaku is great because it incorporates both art and science into a fun learning experience. While the children are looking at the fish they can learn fish anatomy (see resources below) and also details useful in identification of individual species. There are loads of places to learn more about gyotaku on the Internet, just load up your favorite search engine and go.

Try this gyotaku lesson plan at ArtsEdge for ideas.

Dick Blick art supplies has a model sea horse.

Acorn Naturalists also sells gyotaku supplies.

2. Moving Through the Water.

Different fish have different shaped bodies. Do some move through the water more easily than others?

(See fish body shapes .pdf in resources below) Edit: no longer available

Gather:

• modeling clay
• string or yarn
• scissors
• sink with water

Cut a few pieces of string about 18 inches long (at least two). Form a few golf ball-sized lumps, the same number as pieces of string. Take a small lump of clay and wrap around one end of the string, so the string is embedded. Form the lump into a rough sea horse shape. Now take another ball of clay and wrap around another piece of string. Form this into a typical fish shape, such as a trout. This shape is called fusiform. Put each shape into the sink and drag across the water. Does one shape move more easily than others? Try some other fish shapes as well. Which shape moves through the water most easily?

Resources:

Nova Program: Kingdom of the Seahorse Resources

National Geographic Seahorse

Tennessee Aquarium Seahorses

Now it is time to finish our summer beach science series and get ready for fall. We'll miss the sand between our toes (although I think I still have some in my hair), but look forward to a brisk change of pace and some autumn foliage.

To check the rest of the posts on beach science, follow these links:

Shore Birds

Tide Pool Invertebrates

Beach Science- Boats

Beach Science Algae

Beach Science-Sand

Beach Science-Seawater