The Central Coast of California has a Mediterranean climate – warm and dry in the summer and cooler and wetter in the winter. Inland areas tend to be hotter in summer and colder in winter.

Coastal climates have relatively dry summers and wet winters and are restricted to coastal areas. Inland climates, on the other hand, have dry winters and more humid summers, cover very large areas in continental interiors, and are more distinguished by temperature.

Short definition: Coastal areas are local administrative units (LAUs) that are bordering or close to a coastline. A coastline is defined as the line where land and water surfaces meet (border each other).

A coast is a strip of land that meets an ocean or sea. Coasts have many different features, such as caves and cliffs, beaches and mudflats. Tides, waves, and water currents (flow) shape the land to form these coastal features.

Human activities in coastal areas have affected many of the natural environmental processes there. This has led to a wide range of issues including a loss of biodiversity, high levels of pollution, erosion, and rising sea levels due to climate change. In fact, coasts are one of the Earth’s most threatened environments.

Coastal Processes

• Waves.
• Tides.
• Near-Shore Currents.
• Shoreline Weathering.
• Coastal Erosion.
• Sediment Transport and Deposition.
• Organic Activity.
• Changes in Sea Level.

There are four main processes of coastal erosion. These are corrasion, abrasion, hydraulic action and attrition. Corrasion is when destructive waves pick up beach material (e.g. pebbles) and hurl them at the base of a cliff.

Storms. The main threats associated with these hazards are storm surge, high winds, heavy rain and flooding, as well as tornadoes. Winter storms can produce rough lake conditions, coastal flooding, and beach erosion. Strong winter storms are also responsible for significant land losses around the Great Lakes.

For example, storms, hurricanes, and tsunamis are natural driving forces of coastal processes and landforms, but also cause loss of life and property in coastal communities. Storms provide much of the sediment to shallow-marine and estuarine ecosystems.

Seawalls and other shore-parallel structures (such as revetments and bulkheads; Figure 3-3) are built to reduce coastal risks to infrastructure where the natural beaches and dunes have been eliminated or significantly restricted and where other risk reduction options are prevented by lack of space or sediment.

Coastal erosion may be caused by hydraulic action, abrasion, impact and corrosion by wind and water, and other forces, natural or unnatural. On non-rocky coasts, coastal erosion results in rock formations in areas where the coastline contains rock layers or fracture zones with varying resistance to erosion.

However, human activities can also strongly influence the propensity of landforms to erode. For example, the construction of coastal structures (such as breakwaters, groynes and seawalls) can lead to changes in coastal sediment transport pathways, resulting in erosion in some areas and accretion in others.

Benefits of Coastal Landscaping

• Erosion Control. Along the coast, beaches and dunes are constantly moving with winds and waves, coastal banks are eroding, and large amounts of sand are shifted during big storms.
• Pollution Buffer.
• Wildlife Habitat and Natural Beauty.
• Lower Maintenance Needs.

In the Louisiana study, a Louisiana State University economist estimated that even a three-week disruption in oil supplies resulting from coastal erosion could cost the U.S. economy more than 30,000 jobs and more than $1 billion in earnings over a year.

Already, coastal erosion costs roughly $500 million per year for coastal property loss, including damage to structures and loss of land. Coastal erosion is the process by which local sea level rise, strong wave action, and coastal flooding wear down or carry away rocks, soils, and/or sands along the coast.

Increased temperatures will cause more heatwaves, with impacts on human and ecosystem health, with increased risk of poor health and even death of people, animals and plants. Incremental warming of the ocean will affect ecosystems such as coral reefs.

This will change environmental conditions, increasing the threat to low-lying coastal areas such as marshes and wetlands. Some current areas of salt marsh and wetlands could decrease or even disappear. Saltwater intrusion and the resulting changes in coastal ecosystems are a problem in the northern Curonian Lagoon.

Land management is often used to help protect and rebuild dunes. Sand dunes act as a good barrier against coastal flooding and erosion and they can be exploited as a natural defence against the sea.

Coastal erosion is the wearing away and breaking up of rock along the coast. Destructive waves erode the coastline in a number of ways: Hydraulic action: Air may become trapped in joints and cracks on a cliff face. When a wave breaks, the trapped air is compressed which weakens the cliff and causes erosion.

Coastal Erosion

• Destructive Waves. Coastal erosion takes place with destructive waves.
• Constructive Waves. Constructive waves, on the other hand, are low energy waves that result in the build-up of material on the shoreline.
• How Waves Erode.
• Cliffs.
• Sea Caves.
• Sea Arch.
• Sea Stack.
• Sea Stump.

There are four types of erosion:

• Hydraulic action – this is the sheer power of the waves as they smash against the cliff.
• Abrasion – this is when pebbles grind along a rock platform, much like sandpaper.
• Attrition – this is when rocks that the sea is carrying knock against each other.

The four main types of river erosion are abrasion, attrition, hydraulic action and solution.

Erosional processes along coastlines include: (1) the direct effects of hydraulic action, wedging, and cavitation by waves; (2) abrasion (corrasion), using sand, gravel, and larger rock fragments as tools; (3) attrition of the rock particles themselves during this abrasive action; (4) salt weathering or fretting; (5) …

The Preventive Methods of Beach Erosion

• Groins. Groins look like long walls that are built alongside beaches.
• Breakwaters.
• Jetties. Jetties are perpendicular structures built across the shoreline, extending into the ocean or the sea.
• Erosion Control Mats.
• Breakwater Tubes.
• Geotextiles.
• Coconut Fiber Logs.
• Earth Barrier Walls.

Two natural agents i.e., water and wind, are constantly at work indulging in soil erosion. Therefore, we can talk of two types of soil erosion viz., water erosion and wind erosion.

Erosion involved three processes: detachment (from the ground), transportation (via water or wind), and deposition. The deposition is often in places we don’t want the soil such as streams, lakes, reservoirs, or deltas.

The three main forces that cause erosion are water, wind, and ice. Water is the main cause of erosion on Earth.