GLY 4734

Societal Reasons

Hazard/Event-based Reasons

Geologic Reasons

Why is the coast important to study?

Societal Reasons - Coastal Population

30 coastal states contain 62% of US population and 12/13 largest cities

53% of US pop. lives w/in 50 miles of the shore (83% in Australia)

in 1973: 440,000 km of global coastline / 3.3 billion humans = 13 cm each

today: 440,000 km of global coastline / 6.7 billion humans = 6.5 cm each

Sand Key, FL

Development along our coastlines continues to expand

Societal Reasons – Coastal Development

Populations PressuresTransportationSafetyInfrastructure

Alsea Bay, Waldport, OR - Photo credit: Paul Komar

Societal Reasons – Coastal Infrastructure

Concept of dynamic equilibrium

Construction of Aswan Dam has shut off sediment supply

Result: rapid coastal recession rates = 50-100 m/yr

Societal Reasons - Agricultural Example: Nile Delta

Coastal Hazards - Hurricanes

Dauphine Island, Alabama

LIDAR data - newish technology

Hazards/Climate Reasons – Example: Hurricanes Ivan and Katrina

LIDAR surveys - Dauphine Island, Gulf Coast of Alabama

Hazards/Climate Reasons – Landform changes caused by the storm events

Hazards/Climate Reasons - Sea Level Rise

Gainesville

Hazards/Climate Reasons - Sea Cliff Retreat Examples

Biota, Habitat, Ecological Reasons

UpliftSea Level Change

Wave Transformation

Wave EnergyImparted to Coast

Lithologic Response

Offshore Wave Climate

Beaches

Geologic Reasons – Generation of Stratigraphy

UpliftSea Level Change

Wave Transformation

Wave EnergyImparted to Coast

Lithologic Response

Offshore Wave Climate

Beaches

History of Science of Coastal Geomorphology

UpliftSea Level Change

Wave Transformation

Wave EnergyImparted to Coast

Lithologic Response

Offshore Wave Climate

Beaches

Greeks (Herodotus) and the Nile 'delta'

da Vinci and the Pontine Marshes in Italy - 15th century

Captain Cook's voyages shed light on many coastal reaches worldwide

Early geologists (Hutton, Lyell) recognized the coast as a modern depositional environment responsible for sedimentary rock generation.

Early geomorphologists (de Beaumont, Huxley) identified the link between process and form along the coast.

Darwin theorized on the origins and evolution of reefs and atolls.

Even Grove Karl Gilbert interpreted abandoned terraces in Utah to testify to the presence of Pleistocene lakes in the western U.S.

Early 20th century: Douglas Johnson's application of William Morris Davis's "geographical cycle" -New England coast

World War II and in the Cold War era which followed - scientists at Scripps Institution of Oceanography (Sverdrup, Munk, Shepard, and Inman)

In-Class Exercise

Name and where are you “from”?

What coast are you most familiar with or are you currently interested in?

What are some issues there that grab your attention?

During the semester, consider how each topic we cover affects your coast (i.e. tectonics, wave climate, sediment supply/local rivers, population/human infrastructure, hazard vulnerability).

I'll start with an example...

South-Central Alaska