PHYSICAL WORLD ESCI 243  -  NICHOLS COLLEGE ONLINE COURSE

Professor Mauri S. Pelto, 508-213-2168 peltoms@nichols.edu   

Coastal Management

Home Page Plate Tectonic Setting Earthquakes Volcanic Hazards Glaciers-Sea Level Rise Coastal Management
Water Resources Groundwater Management Global Warming Fossil Fuel Resources Alternative Energy Sources River Types-Flooding
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Hurricane Charley		 v
Wave Heights Hurricane Frances
With sea level rising and the continuing coastal storms our shorelines will continue to retreat.  For a beach to survive, it must be in equilibrium.  To be in equilibrium, in the absence of a coral reef, requires not interruption in longshore transport, no abrupt changes in slope, and ability to migrate inland via wave overwash and the presence of dunes.

Readings: 150-168

Concept Questions:

1.  What is longshore transport and how can it be interrupted?

2.  What process allows beaches to migrate inland?  What happens if they cannot with rising sea level?

3.  What are the affects of hard stabilization on beaches?

4.   Look at the following images and answer the questions.

Assignment:   Determine when or if beach nourishment should be used on Destin beach based on its environmental and cost effectiveness.  Nourishment

5.What factors cause hurricanes to form?  How accurate have the prediction for Ivan and Frances been? Military

Field Project:  Examine a beach you visit and report on its status.  This will entail determining: This is due simply by the end of the semester, but the weather is better now.

1)Longshore Transport direction and potential interruptions

2)Health of dunes.

3) Nature of the beach slope and existence of offshore bars.

4.  Development on-behind the beach that could affect its ability to migrate.

5)  Recent changes in the beach.

6)Current management of the beach

7) You need images of the beach to explain.

 

Notes: 

To be in equilibrium a beach must have dunes, be able to migrate inland by wave overwash, have no abrupt slope changes and have no interruptions in longshore transport.  Beaches lacking dunes, having abrupt slopes changes, barriers or development preventing longshore transport or wave overwash are not in equilibrium. 

Table 1. Estimated potential maximum sea-level rise from the total melting of present-day glaciers.
 
table 1
 
Beach on left not in equilibrium because of groins interrupting Longshore transport.  The longshore transport is going south. Beach below is ovewhelmed by storm surge taking out wrath on seawall. 

 

Equilibrium beach no LST interrruptions, no steep slopes, ability to migrate inland and dunes are present.
Longshore transport interruption causing buildup of sand on lower beach erosion on upper beach.

No dunes, no ability to migrate, longshore transport interruptions, beach not in equilibrium