Ocean Currents and Shoreline Features

Thermohaline Circulation

• Driven by variations in water density, influenced by temperature (thermo) and salinity (haline)
• Warm, less salty surface water flows towards the poles
• Water cools and becomes saltier, increasing density, leading to sinking
• Cold, dense water flows along the ocean floor towards the equator
• This deep flow eventually upwells, bringing nutrients and contributing to surface current patterns

Global Water Movements

• Surface currents driven by wind patterns
• Deep ocean currents driven by density differences
• These combined currents form a global network of circulating water
• Surface currents transport heat, influencing regional climates
• Deep currents play a crucial role in nutrient distribution and oxygenation

Shoreline Features

Wave Erosion

• Wave-cut platform: a flat, rocky surface created by wave erosion at the base of a cliff
• Cliffs: steep, vertical rock faces formed by wave erosion
• Terraces: step-like platforms created by wave erosion and uplift
• Sea arches: natural archways formed by wave erosion through headlands
• Sea stacks: isolated rock formations left behind after wave erosion of headlands

Sediment Deposition

• Spits: narrow sand deposits extending from the coastline
• Bars: submerged or exposed sand deposits parallel to the coast
• Tombolos: sand deposits connecting an island to the mainland
• Barrier Islands: long, narrow islands separated from the mainland by lagoons

Wave Structure

• Crest: highest point of a wave
• Trough: lowest point of a wave
• Wavelength: distance between two successive crests or troughs
• Wave height: vertical distance between the crest and trough
• Wave period: time it takes for one complete wave cycle to pass a given point

Wave Interaction with the Seafloor

• Wave "feels bottom" when depth is less than half the wavelength
• Wave breaks when the depth is about 1.3 times the wave height

Tides

• Regular rise and fall of sea level caused by gravitational pull of the Moon and Sun
• Moon's gravitational pull is stronger than the Sun's due to its proximity to Earth

Spring Tides

• Earth, Moon, and Sun aligned (new moon or full moon)
• Strongest gravitational pull
• Highest high tides and lowest low tides

Neap Tides

• Earth, Moon, and Sun at 90° angles (first or third quarter moon)
• Weaker gravitational pull
• Lower high tides and higher low tides

Tidal Patterns

• Diurnal: One high and one low tide each day
• Semidiurnal: Two high and two low tides each day
• Mixed: Two high tides and two low tides each day, with unequal heights

Explore the fascinating dynamics of thermohaline circulation and how it influences global water movements. This quiz also delves into the effects of wave erosion on shoreline features, such as wave-cut platforms and cliffs. Test your understanding of ocean currents and coastal geography.