UMass Amherst GEO-SCI 103 - Sea Level Rise and Coastal Hazards (3 pages)

Previewing page 1 of 3 page document View the full content.
View Full Document

Sea Level Rise and Coastal Hazards

Previewing page 1 of actual document.

View the full content.
View Full Document
View Full Document

Sea Level Rise and Coastal Hazards


Examination of storm surges on coastlines and beaches in addition to causes and effects of global warming and rising sea levels.

Lecture number:
Lecture Note
University of Massachusetts Amherst
Geo-Sci 103 - Intro Oceanography GenEd: PS
Unformatted text preview:

GEO SCI 103 Lecture 21 Outline of Current Lecture Sea Level Rise and Coastal Hazards pgs 250 257 I II III Storm Surge and Tsunami Coastal Hazards Global Warming and the Ocean System Sea level Rise and Shoreline Retreat Current Lecture I Storm Surge and Tsunami Coastal Hazards Coastline can be altered dramatically in a matter of hours with severe storm strikes to the shore Erosion bound to occur mounds of sand The intensity of a storm surge can reach over dunes on a beach causing widespread erosion and property destruction A Storm Surge a Water pushed strongly landward by winds and the forward direction of storm track b Surface of water is doomed up under intense low pressure of storm c Danger further compounded if landfall coincides with high tide d Strong onshore flow to the right eye area of greatest danger threat of storm surge e Where winds are pushing on the shore increasing the energy of the advancing water f Associated with extra tropical storms that form on the outside tropics like the nor easters that occur along the East coast during winter g Water and waves can breach the barrier dunes causing sand to be deposited in washover fans on the landward side of the dunes h Pushes beach landward as it adjusts to sea level changes and all other coastal environments retain their original position relative to the beach as they move gradually farther inland B Tsunami a Large waves generated by major earthquakes b Associated with subduction of oceanic crust These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute c Long wavelength L 200 km d Height at outset is low but because of long wavelength they move fast e Height increases and speed slows as they move away from epicenter C Hurricane a Large powerful tropical cyclone feeds on heat of ocean b Intense low atmospheric pressure circulation is counterclockwise in the N Hemisphere clockwise in the S Hemisphere c Strong sustained winds d Bands of heavy rain II Global Warming and the Ocean System A Sea Level Rise a As temperature warms polar ice caps will melt b Volume of ocean will expand as the temperature of the water increases B The ocean conveyor a Global climate is dependent upon the movement of surface and thermohaline currents b Changes in the temperature or salinity of sea water could have major effects upon the world climate system C Ocean Chemistry a About half of the carbon dioxide that the industrial revolution pumped into the atmosphere has disappeared dissolved in ocean b CO2 H20 H2CO3 H CHO3 carbon dioxide III Sea Level Rise and Shoreline Retreat A real Threat A Coastal Environments with Rising Sea Level a Along gently sloping coastlines even a small rise in the sea level can have a major effect on the landward migration of the coastline b Small rise of sea level across a low lying coastal plain translates into a significant advance of the sea or retreat of the shoreline c Coastal environments retain their original profile as they role landward with rising sea level d With rising sea level sand washes over the dunes and buries the marshes and mudflats and eventually fills in the bays lagoons as the shoreline retreats and the beach and dunes migrate landward IV Options in the Face of Rising Sea Level A Hard Stabilization a Armoring of the coast with rocks and mammade structures is designed to protect the coast from erosion trap sand or redirect wave energy b Seawalls solid walls of rock timbers concrete built parallel to the shore with intent to protect buildings from washing into sea They can collapse during storms increasing both the amount of erosion resulting property damage c Jetties long structures build perpendicular to the shore Protects harbor or channel inlet from incoming swell Sand accumulates on the updrift side and a sand split will develop at the end of the jetty to prevent the inlet from being filled with sand d Groins short structures built perpendicular to the shore art way across the surf zone Traps sand from longshore transport system and widen an eroding beach Sand will accumulate on the updrift side and cause erosion on the down drift side e Breakwaters rigid structures built a short distance from and parallel to the shore Provides quieter water for boat anchorage Disrupts incoming swell which provides the energy to move sand via longshore drift sand accumulates in quieter water behind the breakwater must be dredged B Soft Stabilization a Beach nourishment intended to replace the sand that has been lost from the longshore transport system C Relocation a Movement of structures is an option that will preserve the natural character of the beach

View Full Document

Access the best Study Guides, Lecture Notes and Practice Exams

Loading Unlocking...

Join to view Sea Level Rise and Coastal Hazards and access 3M+ class-specific study document.

We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Sea Level Rise and Coastal Hazards and access 3M+ class-specific study document.


By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?