Coastal Processes: Waves

Coastal Processes

Waves

• Formation: Waves are formed by wind friction on the surface of the ocean, transferring energy from the wind to the water.
• Types:
  • Constructive waves: Build up the beach, low energy, long wavelength.
  • Destructive waves: Erode the beach, high energy, short wavelength.
• Characteristics:
  • Wave height: The vertical distance between the trough and crest.
  • Wave period: The time between two consecutive wave crests.
  • Wavelength: The distance between two consecutive wave crests.

Tides

• Definition: The periodic rising and falling of the sea level caused by the gravitational attraction of the Moon and Sun.
• Types:
  • Semidiurnal tides: Two high and two low tides each day, most common type.
  • Diurnal tides: One high and one low tide each day.
  • Mixed tides: Combination of semidiurnal and diurnal tides.
• Factors affecting tides:
  • Moon's orbit: The Moon's elliptical orbit affects the strength of its gravitational pull.
  • Sun's gravitational pull: The Sun's gravitational pull also affects the tides, although it's weaker than the Moon's.
  • Wind and atmospheric pressure: Can cause changes in sea level, modifying the tidal pattern.

Coastal Erosion and Deposition

• Erosion: The process of wearing away or removal of rock and soil from the coastline.
• Deposition: The process of sediment accumulation and deposition along the coastline.
• Factors influencing erosion and deposition:
  • Wave energy: High-energy waves cause erosion, while low-energy waves cause deposition.
  • Tidal range: The difference between high and low tide affects the area of the coastline exposed to erosion and deposition.
  • Sediment supply: The availability of sediment affects the rate of deposition.

Coastal Landforms

• Beaches: Accumulations of sediment along the coastline, shaped by wave action and tidal currents.
• Cliffs: Steep rock faces formed by erosion, often found along coastlines with high wave energy.
• Headlands: Rocky promontories that extend out to sea, formed by erosion and deposition.
• Bays: Curved or circular inlets of the sea, often formed by erosion and deposition.

Human Impact on Coastal Processes

• Coastal development: Construction of buildings, infrastructure, and other human-made structures along the coastline.
• Coastal protection: Measures taken to prevent or mitigate coastal erosion and flooding, such as seawalls and breakwaters.
• Beach nourishment: The process of pumping sand onto a beach to widen or restore it, often used to combat erosion.

Coastal Processes

Waves

• Wind friction on the ocean surface forms waves, transferring energy from wind to water.
• There are two main types of waves: constructive and destructive.
• Constructive waves have low energy, long wavelength, and build up the beach.
• Destructive waves have high energy, short wavelength, and erode the beach.
• Wave characteristics include:
  • Wave height: the vertical distance between the trough and crest.
  • Wave period: the time between two consecutive wave crests.
  • Wavelength: the distance between two consecutive wave crests.

Tides

• Tides are the periodic rising and falling of the sea level caused by the Moon and Sun's gravitational attraction.
• There are three types of tides: semidiurnal, diurnal, and mixed.
• Semidiurnal tides have two high and two low tides each day, and are the most common type.
• Diurnal tides have one high and one low tide each day.
• Mixed tides are a combination of semidiurnal and diurnal tides.
• Factors affecting tides include:
  • The Moon's elliptical orbit, which affects the strength of its gravitational pull.
  • The Sun's gravitational pull, which is weaker than the Moon's.
  • Wind and atmospheric pressure, which can cause changes in sea level and modify the tidal pattern.

Coastal Erosion and Deposition

• Erosion is the process of wearing away or removal of rock and soil from the coastline.
• Deposition is the process of sediment accumulation and deposition along the coastline.
• Factors influencing erosion and deposition include:
  • Wave energy: high-energy waves cause erosion, while low-energy waves cause deposition.
  • Tidal range: the difference between high and low tide affects the area of the coastline exposed to erosion and deposition.
  • Sediment supply: the availability of sediment affects the rate of deposition.

Coastal Landforms

• Beaches are accumulations of sediment along the coastline, shaped by wave action and tidal currents.
• Cliffs are steep rock faces formed by erosion, often found along coastlines with high wave energy.
• Headlands are rocky promontories that extend out to sea, formed by erosion and deposition.
• Bays are curved or circular inlets of the sea, often formed by erosion and deposition.

Human Impact on Coastal Processes

• Coastal development involves constructing buildings, infrastructure, and other human-made structures along the coastline.
• Coastal protection measures are taken to prevent or mitigate coastal erosion and flooding, such as seawalls and breakwaters.
• Beach nourishment is the process of pumping sand onto a beach to widen or restore it, often used to combat erosion.

Definition of Swash

• A swash is a decorative flourish or ornamental stroke used in handwriting and typography to add aesthetic appeal to a letterform or symbol.

Characteristics of Swashes

• Found in various forms, such as extended flourishes connecting letters or words, decorative endings or beginnings of strokes, and intricate patterns or ornaments within or around letters.

Uses of Swashes

• Commonly used in calligraphy and handwritten scripts to add elegance and sophistication.
• Used in typography, particularly in display fonts and logos, to create visual interest and emphasize certain words or phrases.
• Used in artistic and decorative writing to convey a sense of luxury, creativity, or craftsmanship.

Purpose of Swashes

• Add elegance and sophistication to written text.
• Create visual interest and emphasize certain words or phrases.
• Convey a sense of luxury, creativity, or craftsmanship.
• Enhance the aesthetic appeal of a design or layout.

Examples of Swashes

• Copperplate script, a popular calligraphic style, often features elaborate swashes.
• The font "Lobster" is a modern script font that includes swashes in its design.
• Decorative initial letters in illuminated manuscripts often feature intricate swashes.

Wind Direction

• Wind direction is the direction from which the wind is coming, and it's essential for understanding weather patterns, climate, and wind-related phenomena.

Measurement of Wind Direction

• Measured in degrees, with 0° being north, 90° being east, 180° being south, and 270° being west.
• Measured using a wind vane or an anemometer.

Types of Wind Direction

• Global wind patterns: Large-scale wind patterns that circle the Earth, including trade winds, westerlies, and jet streams.
• Local wind patterns: Smaller-scale wind patterns influenced by local topography, land use, and weather systems.

Factors Affecting Wind Direction

• Pressure gradient: Air moves from high pressure to low pressure, influencing wind direction.
• Coriolis force: The Earth's rotation deflects wind to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.
• Topography: Mountains, hills, and valleys can block or redirect airflow, altering wind direction.

Importance of Wind Direction

• Weather forecasting: Wind direction predicts weather patterns, including storms, fronts, and temperature changes.
• Climate: Wind direction influences regional climate, with specific directions associated with specific weather conditions.
• Wind energy: Wind direction is crucial for optimizing wind turbine placement to maximize energy generation.

Learn about the formation, types, and characteristics of waves, including constructive and destructive waves, wave height, and wave period.