Fig. 5.1. Rugged rocky coastline, Big Sur region, California
Image courtesy of NOAA
Fig. 5.1. Rugged rocky coastline, Big Sur region, California
Image courtesy of NOAA
The coastline is the boundary between the ocean and the land. The term “coastal zone” is sometimes used to describe the broader geographical region where the world ocean interacts with land. Coastal zones include rocky shores, dense mangrove forests, and muddy saltmarshes. The features of a particular coastal zone are largely determined by the combined interaction of the local geology, ocean waves and currents, and organisms. Approximately half of the world’s human population lives near the coast and thus can impact, and be impacted, by coastal interactions. A better understanding of coastal interactions can help conserve natural resources, protect valuable property, and save lives.
Principle 2: The ocean and life in the ocean shape the features of Earth.
Ocean Literacy Fundamental Concept: Erosion—the wearing away of rock, soil, and other biotic and abiotic earth materials—occurs in coastal areas as wind, waves, and currents in rivers and the ocean move sediments. (OLP 2c)
Ocean Literacy Fundamental Concept: Sand consists of tiny bits of animals, plants, rocks, and minerals. Most beach sand is eroded from land sources and carried to the coast by rivers, but sand is also eroded from coastal sources by surf. Sand is redistributed by waves and coastal currents seasonally. (OLP 2d)
To build an understanding of how the ocean and ocean life shape Earth’s features, it is important to closely examine coasts where the ocean interacts with landmasses.
These concepts will be explored in this unit through the following activities and investigations:
There are surf breaks all over the Pacific ocean basin. Using your knowledge of breaking waves and wave properties, investigate why certain surf breaks are good for surfing.
Make a beach profile, or side view, showing the shape of the beach. You can use the same procedure to make a profile of the area outside your classroom.
Analyze the composition of beach sediments by looking at sand size, shape, and source.
Design a survey to characterize beach sand and investigate the variation in sand composition at a local beach.
Waves move sand and rocks in predictable ways, which can guide safe beach activity and building practices. Investigate the effect of coastal engineering and offshore building designs on a shoreline.