Coastal Landscapes and Earth's Life Support Systems

Vocabulary flashcards covering the key concepts of coastal landscape systems, including geomorphic processes, landforms, and the Earth's life support systems (water and carbon cycles) as detailed in the lecture transcript.

Lithology

The chemical and physical characteristics of rock types which impacts a coastal landform’s susceptibility to geomorphic processes like erosion and weathering.

Structure

The arrangement of rocks, such as bands of alternating rock types perpendicular or parallel to the coastline, which influences morphology.

Discordant Coastline

A coastline where the geology consists of bands of alternating rock types perpendicular to the shore, typically forming headlands and bays.

Concordant Coastline

A coastline where bands of rock are parallel to the sea, such as the coastline at Lulworth Cove.

Differential Erosion

The process where weaker rock types, such as Wealden Clay, erode faster than resistant rocks, such as Portland limestone, creating inlets or bays.

Wave Refraction

The process where waves bend around headlands, concentrating kinetic energy and erosional power on the headlands while dispersing energy in sheltered bays.

Eustatic Sea Level Change

A global change in sea level caused by the melting of ice sheets or thermal contraction/expansion of seawater.

Ria

A submergent landform consisting of a flooded V-shaped river valley, modified by fluvial and subaerial erosion to be gently sloping.

Rock Groynes

Hard engineering structures, such as the $3-6$ tonne boulders of Portland limestone used at Sandbanks, designed to interrupt longshore drift and trap sediment.

Dynamic Equilibrium

A state of balance within a coastal or cycle system where inputs and outputs are equal, often restored by feedback loops.

Positive Feedback Loop

A process where an initial change triggers further changes that amplify the original process, such as spit growth encouraging further sediment trapping.

Negative Feedback Loop

A process where a system responds to a change by initiating a sequence that counteracts the change, such as a wave-cut platform dissipating energy to slow cliff erosion.

Longshore Drift

The movement of sediment along the coastline by wave action when waves approach the shore at an angle.

Wave-cut Notch

An undercut feature formed at the base of a cliff around the high tide mark due to repeated hydraulic action and abrasion.

Emergent Landforms

Coastal features raised above the current sea level due to eustatic fall, including raised beaches, relict cliffs, and marine terraces.

Relict Cliff

A cliff no longer actively eroded by the sea following a sea level fall, characterized by a decreasing gradient as sub-aerial processes dominate.

Flandrian Transgression

The period of post-glacial sea level rise that subjected previously emergent landforms to marine processes.

Hydrosphere

The Earth system containing all water, with the oceans acting as the largest store.

Thermoregulation

The physiological process by which animals maintain internal temperature, aided by water's high latent heat as hydrogen bonds break during evaporation.

Cell Turgidity

The pressure of water inside plant cells that provides structural support, allowing leaves to remain exposed for light absorption.

Evapotranspiration

The combined transfer of water to the atmosphere through evaporation from surfaces and transpiration from plant leaves.

Short-term Carbon Cycle

The rapid transfer of carbon between the atmosphere, biosphere, and surface water over days to years, primarily through photosynthesis and respiration.

Long-term Carbon Cycle

The storage and transfer of carbon in rocks, oceans, and fossil fuels over thousands to millions of years.

Arctic Amplification

The phenomenon where rising greenhouse gas emissions cause Arctic temperatures to increase at a faster rate than the global average.

Permafrost

Frozen ground that acts as a long-term carbon sink but releases $CO_2$ and methane when thawed due to human-induced warming.

Thermokarst Lakes

Lakes formed in the Arctic when the thawing of permafrost causes the ground to collapse, altering natural drainage patterns.

REDD+

A global management strategy (Reducing Emissions from Deforestation and Forest Degradation) that provides financial incentives for forest conservation.

Albedo

The reflectivity of a surface; for example, increased cloud formation reflects solar radiation, acting as a negative feedback mechanism.

Carbon Sequestration

The process by which carbon sinks, such as forests or wetlands, absorb and store $CO_2$ from the atmosphere.

Chemical Weathering

A process where rainwater made slightly acidic by dissolved $CO_2$ reacts with rocks like limestone, eventually storing carbon in the lithosphere as bicarbonate ions.