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.