The Edge of the Sea Is a Strange and Wonderful Place
Rachel Carson

Diversity of Coastal Geomorphology - History of Coastal Research

Types of Coastal Formations
Zones of transition between the ocean and land, where waves, currents, and tides act to mold the landforms, which in turn influence the movement of the water
Width of coasts
Less than 1 km on cliffed coasts or more than 100 km in large estuaries (Delaware Bay)
Pocket beaches on the Pacific Coast – long and wide beaches on East Coast and Gulf Coast
History of Coastal Research
Scientists have only recently undertaken comprehensive investigations of the coast
First systematic studies of coasts were conducted by geomorphologists in the early 20th  Century
How coasts evolved
Processes by which coasts are changed and formed
Engineers constructed harbors, docks, and bridges; stabilize and protect the open coasts
Most often to prevent, or at least slow erosion
Examples: Holland and Germany protect and reclaim shorelines by building dikes
Before WW II, the focus was to understand and control coasts
During the war, interest in coastal geomorphology and coastal processes was emphasized
Waves, tides, currents, and hydrological patterns along coasts
Most of the coasts throughout the world were mapped in detail
After WW II, emphasis was shifted to engineering and global study of river deltas (Mississippi);
Research broadened to include beaches, inlets, and deltas of the of the world’s coasts, all potential settings for military activity
Modern Era of Coastal Research: 1960’s and 1970’s
Research was conducted primarily by university researchers who studied open coastal environments
Broadened and expanded coastal research centers
More recent trends – last 30 years
Coastal protection programs have expanded worldwide
New agencies and management plans for addressing coastal development and wetlands degradation

East/West Coasts of the U.S.
East Coast
Wide coastal zones stretch to the sea, marked by wide beaches and high dunes, deltas, and barrier islands
Trailing coast
Deposition of sediment is dominant
West Coast
Bedrock headlands interrupted by pocket beaches
Erosion of sediment is dominant
Process of erosion and deposition create landforms of great variety
East Coast Examples
More East Coast Examples
Pacific Coast Examples
Coastal Processes
Coastal processes may work in a short time (days) or long time (years)
Examples:
Winter storms and swift tidal currents cause short term changes
Geological development can be observed in only a few years
Overall development of the coastal areas took as long as 180 million years to develop--period since the breakup of the continents
Examples of Patterns
Days/Years: action of waves, currents, and tides
Thousands of Years: gradual sea level changes
Global climate changes with temperatures falling for 1000’s of years, then rising for 1000’s of years
Sea levels now rising about 1-2 mm per year
Result in long and slow, but steady, change
Millions of years: mountain formation and erosion
Effects of Short Term and Long Term Processes
The combination of short-term and long-term processes produces the deltas, estuaries and barrier islands (deposition activity) and the rocky coastlines (erosion activity)

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