Getting to Know the Marine Environment

Have you ever stood at the edge of the ocean, looking out across the endless blue, wondering what's out there? Pretend you're there right now. Your toes squish into the wet sand, and the sun is warm on your skin. A cool ocean breeze kisses your face. The air smells like salt and coconut-scented sunscreen. As the water pooled around your ankles gets pulled back to sea, your feet sink further into the sand. A wave comes crashing down and rushes past you with a hissss, spraying your shins with foamy seawater.

As you stand on the beach in your imagination, look out as far as you can. What do you see? Imagine that somewhere on the other side of the ocean, maybe thousands of miles away, there's another kid about your age looking out at the same endless blue. What lies between you and him may look like a bunch of nothing, but really, it's more than you can imagine.

For centuries, humans have gazed toward the horizon and wondered what mysteries the ocean holds. Some have sailed across it, returning home with tales of beautiful mermaids, salty pirates, epic storms, giant swells, spooky shipwrecks, and slithery sea monsters. Others set out to sea and never came back at all. The ocean is a place of fantasy, adventure, and danger. It's a place full of wonder that raises more questions than it answers.

Aboard HMS Challenger

When HMS Challenger set sail from England in December 1872, the scientists on board had an enormous task ahead of them — to learn everything they could about the sea. Challenger sailed for nearly four years across all major oceans except the Arctic, perhaps because the wooden Challenger couldn't take on the icy waters.

Charles Wyville Thomson, the expedition's head scientist, and his team made observations and collected samples at 362 points along the journey. At each station, they measured the depth of the seafloor, took the water temperature, observed the speed and direction of ocean currents, and gathered samples of living things at different depths.

After the expedition ended in May 1876, scientists pored over the information and examined the samples brought back by the Challenger team. They compiled the results of the journey into a 50-volume report.

The 1872-1876 Challenger expedition was the first to accomplish ocean research on such a big scale. To this day, it is one of the most important events in the history of marine science. Even though Challenger's crew did not have access to the same technology that scientists have access to today, much of the data they collected was accurate.

Humans are drawn to the sea because it makes us curious, but we also depend on it for food and other resources, as well as transportation. The ocean helps make life on Planet Earth possible. It absorbs heat from the sun and moves this heat around, keeping temperatures on land from becoming too extreme. The tiny marine plants that live in the ocean create oxygen that humans and other land animals breathe.

Even though humans can visit the underwater world, we haven't spent enough time there to know all of its secrets. Marine scientists, people who study marine science, help fill in the gaps by learning about the ocean, marine ecosystems, and marine life.

A Stroll on the Ocean Floor

If you could take a stroll along the ocean floor, would it be flat or hilly? Would there be tall mountains and steep cliffs like there are on land? By using sonar to map the seafloor, scientists know the answer to this last question is yes. Beneath the ocean's surface lie mountain ranges, volcanoes, submarine canyons, and oceanic trenches that dwarf the mountain ranges, volcanoes, and canyons on land.

Starting on the beach, if you walked straight out into the water, you'd be walking out on a continental shelf, the edge of a continent that's covered by shallow sea. If you could keep walking, you'd eventually reach a steep slope called the continental slope, followed by a gentler slope called the continental rise.

ACTIVITY

Bake a Cookie Earth

To understand why the ocean is so important, it helps to visualize how watery Earth really is. About 70 percent of the planet is covered by ocean, but to get a good sense of what this looks like, make some cookie calculations. Use a family sugar cookie recipe, or buy a package of sugar cookie mix.

ADULT SUPERVISION REQUIRED

YOU'LL NEED

* Sugar cookie dough

* Oven

* Parchment paper

* Flour

* Rolling pin

* Plastic bottle cap

* 2 cookie sheets

* Butter knife

* Blue frosting

* Green frosting

* Red frosting (optional)

1. Prepare your cookie dough by following a recipe or the directions on a package of sugar cookie mix. Using a mix often requires adding butter, an egg, and a little bit of flour.

2. Preheat the oven to whatever temperature the directions on the package or the recipe indicates.

3. Spread parchment paper on a flat surface and sprinkle some flour on top. Use clean hands to place the dough on the parchment paper.

4. Roll out the dough with a rolling pin until it's about ½-inch (1 1/4-cm) thick.

5. Use a clean plastic bottle cap as a cookie cutter to punch 50 tiny cookie cutouts in the dough. It works best to press the bottle cap into the dough and then twist it a couple of times to make sure the cookie is separated from the rest of the dough.

6. Line two cookie sheets with parchment paper and place the tiny cookies on them, about an inch (2½ cm) apart. Two batches may be necessary.

7. Bake the cookies for about 8-10 minutes (time will vary depending on the recipe you're using), keeping an eye on them to make sure they don't get brown. Finished cookies should be firm when cooled but still light in color.

8. Place the cookies on a cooling rack or plate to cool.

9. Once the cookies have completely cooled, lay...