1. The Coast temporary junctions between land and sea
are subject to change
waves, currents, tides, biological processes, tectonic activity
position changes as sea-level does

4. Sea level 18,000 years ago during last ice age

5. If sea level rises 60cm (20ft)

6. Red areas will flood in about 100-200 years
Blue areas may flood over several centuries

7. Red areas would flood during spring high tides
Over the next century, sea level is most likely to rise cm along most of the U.S. Atlantic
Red areas would flood during spring high tides

8. Sea Level Rise Does Matter
Superstorm Sandy produced record storm surge levels for locations in and around the NY City metropolitan region
Sea levels have risen more than a foot in the New York City region since the Industrial Revolution.
So what difference did this extra foot make for the citizens of New York City? Quite a lot. 6,000 more people impacted for each inch of rise!
70,929 more people and 30,551 more homes flooded.
According to Dr. Ben Strauss, Chief Operating Officer and Director of the Program on Sea Level Rise at Climate Central

9. Beaches a zone of loose particles that covers part of the shore
extends from a landward limit
cliff, permanent dunes, seawall
extends to the seaward limit where movement of sediment on and offshore ceases

10. Figure 10.1

11. Beach Profiles Steepness of beaches change with seasons and storms
Summer and calm periods build up beaches
Swash dominates (soaks into beach), less backwash
Winter and storms erode and flatten beaches
Backwash dominates, very little swash soaks in because beach is saturated)

12. Figure 10.2a
Wide berm
Steep beach face

13. Figure 10.2d
Narrow berm
Flatter beach face
longshore bar

15. Seasonal Changes on a beach in California
Figure 11.13
As seasons change, sand moves on and off Boomer Beach near La Jolla, California. Gentle summer waves move sand onshore (a), but larger winter waves remove the sand to offshore bars, exposing the basement rock (b). (c) The annual progression of sand onshore and offshore for a typical year. East Coast beaches are usually not as seasonally varied, but can change dramatically with the advent of nor’easters or tropical cyclones.
Fig c, p. 254

17. Before and After Sandy
Long Branch, NJ
Mantoloking, NJ

18. Before and After Sandy Cupsogue Beach, Westhampton, NY
Fire Island Nat’l Seashore

19. Beaches
exist in a delicate balance between accumulation and destruction
Waves can transport sand onshore or offshore
Longshore currents transport sand along the coastline

20. Figure 10.3b

21. Barrier Islands Are essentially large sand bars
Protect the coast behind them
Very unstable themselves

22. Figure 10.9
Tom’s River, NJ

23. Heavily developed barrier island: Ocean City, MD

24. Barrier Island Migration
Figure 10.10

25. Figure 11.19
The migration of barrier islands. The heavy black lines south of Ocean City represent jetties constructed in the 1930s to protect the inlet. The jetties disrupt the north-to-south longshore current. As a result, Assateague Island has been starved of sediment and has migrated about 500 meters (1,640 feet) westward.
Fig , p. 258

27. Human Impact on Beaches
Attempts to “save” beaches or property often fail or make matters worse

28. Figure 10.18: Groins

29. Figure 10.19
Shipbottom, NJ

30. Groin Field
Cape May, NJ

31. Figure 10.20: Jetties

32. Figure 10.21
Santa Cruz Harbor, CA

34. Break water
Santa Monica, CA

35. Designed to protect harbors from waves
Can cause excessive erosion, requiring dredging to keep area stable

36. Figure 10.24: Seawalls

37. Alternative:
Beach Replenishment

38. Figure 10.26

39. Figure 10.B: Relocation