Oceanography Lab

In your science notebook, please note the following three hours to observe during the class field trip to Carson Beach:

Tides

Especially during the day, talking about tides is one of the best ways to explore astronomy at the beach. That’s because despite being a phenomenon that happens here on Earth, tides are controlled by the position of the moon.

Essentially, the gravitational pull of the moon tugs on the water in such a way that it collects in two planet-wide waves with their crests in the locations closest to the moon and farthest away from the moon. These are the high tides. The low tides, then, are the wave troughs, halfway between the two high-tide locations. 

That’s a pretty simplistic explanation of the process, but it is essentially what’s happening. For a more complete look at tides, check out this website resource.

Weather Patterns

There are so many different factors that affect the way weather works on earth, but a pretty big one is related to the way that water and land absorb the sun’s heat. That makes places where you can experience both, like the beach, a perfect place for learning! 

Water takes a lot more energy to heat up than something like sand. That’s a large part of why sand can feel so hot underfoot while the water remains chilly. This also has an effect on the air above them. Air over the land heats up quickly, lowering the air pressure above it. The air above the water heats slower because the water under it stays cool. 

The cool air has a higher pressure than the warm air, so it begins to move towards the beach. And that’s why beaches have wind! 

In the evenings, the opposite happens. Once the sun goes down, the sand cools more quickly than the water, and the air moves from the land out to sea. This is just one of the ways that beaches can affect the weather. 

Types of beach

In the movies, beaches are almost always composed of bright white sand and crystal clear seawater, and many popular vacation spots have beaches that look just that way. But there’s actually a ton of variation in beaches across the world! 

In fact, beaches are composed of the very same materials as the lands where they’re located, just worn down by the repeated crashing of the waves. With seven continents and millions of miles of shoreline, there are plenty of different types of beaches out there. 

Spend just a few minutes on almost any beach, and the ocean will soon demonstrate a few of the many ways it can transform the narrow strip of shallow water and adjacent land that makes up the shoreline. With every wave, sediments are deposited and withdrawn in complex ways. On a much larger scale, waves, currents, wind, and tides form complex interactions over time to cause erosion along some stretches of shoreline and accretion (growth) in others.

This is just the beginning, however. Add storms, coastal development, and sea level rise to the mix and the fact of our constantly changing shoreline becomes far more complex. We call thisprocess of simplicity to complexity, "emergence."