FIGURE PAGE 



2-58 Diffraction Diagram for a Gap of Two Wave Lengths and a 



45° Approach Compared with that for a Gap Width /2 Wave 



Lengths with a 90° Approach 2-109 



2-59 Single Breakwater - Refraction - Diffraction Combined. . . 2-111 



2-60 Wave Reflection at Hamlin Beach, New York 2-112 



2-61 Standing Wave (Clapotis) System - Perfect Reflection from 



a Vertical Barrier - Linear Theory 2-114 



2-62 (H^/L^) max vs Beach Slope 2-119 



2-63 X2 vs Beach Slope for Various Values H^/L^ 2-119 



2-64 Wave of Limiting Steepness in Deep Water 2-121 



2-65 Breaker Height Index vs Deep Water Wave Steepness 2-122 



2-66 Dimensionless Depth at Breaking vs Breaker Steepness . . . 2-123 



2-67 Spilling Breaking Wave 2-125 



2-68 Plunging Breaking Wave 2-125 



2-69 Surging Breaking Wave 2-126 



2-70 Collapsing Breaking Wave 2-126 



3-1 Sample Wave Records 3-3 



3-2 Waves in a Coastal Region 3-4 



3-3 Theoretical and Observed Wave-Height Distributions .... 3-7 



3-4 Theoretical and Observed Wave-Height Distributions .... 3-8 



3-5 Theoretical Wave-Height Distributions 3-9 



3-6 Typical Wave Spectra from the Atlantic Coast 3-14 



3-7 Observed and Hindcasted Significant Wave Heights vs Time . 3-18 

 3-8 Map of North Atlantic Grid Points, Ocean Weather Ship 



(OWS) Stations and Argus Island 3-19 



3-9 Surface Synoptic Chart for 0030Z, 27 October 1950 3-23 



3-10 Sample Plotted Report 3-25 



3-11 Geostrophic Wind Scale 3-26 



3-12 Possible Fetch Limitations 3-28 



3-13 Relation of Effective Fetch to Width-Length Ratio for 



Rectangular Fetches 3-31 



3-14 Computation of Effective Fetch for Irregular Shoreline . . 3-32 

 3-15 Deepwater Wave Forecasting Curves (for Fetches of 1 to 



1000 miles) 3-36 



3-16 Deepwater Wave Forecasting Curves (for Fetches of 100 



to More than 1000 miles) 3-37 



3-17 Location of Wave Hindcasting Stations and Summary of 



Synoptic Meterological Observations (SSMO) Areas .... 3-41 



3-18 A Comparison of Shipboard Observations and Hindcasts . . . 3-43 



3-19 Decay Curves 3-44 



3-20 Travel Time of Swell Based on t^, = D/C^ 3-45 



3-21 Forecasting Curves for Shallow-Water Waves; Constant 



Depth = 5 Feet 3-47 



3-22 Forecasting Curves for Shallow-Water Waves; Constant 



Depth = 10 Feet 3-47 



3-23 Forecasting Curves for Shallow-Water Waves; Constant 



Depth = 15 Feet 3-48 



XIII 



