APPENDIX: SHALLOW WATER ENVIRONMENTAL ANALYSIS ... 69 



Introduction ... 69 



Shallow Water Environments ... 69 



Method of Data Analysis ... 69 



Discussion of Selected Shallow Water Environments ... 71 

 NORTH SEA ... 73 

 STRAIT OF JUAN DE FUCA ... 97 

 EAST OF SINGAPORE ... 120 

 LANDS END ... 132 



ILLUSTRATIONS 



2.1 Locations of the shallow water sites . . . page 10 



2.2 Location and surrounding areas of the shallow water sites ... 1 1 



2.3 Types of ideahzed shallow water sound speed profiles ... 15 

 2.4a Examples of positive gradient profiles: Lands End — spring ... 17 

 2.4b Examples of non-positive gradient profiles: Lands End — spring ... 17 



3.1 Chart of local area - North Sea ... 19 



3.2 Characteristic sound speed profiles found at the North Sea site ... 20 



3.3 Chart of local area — Strait of Juan de Fuca ... 22 



3.4 Characteristic sound speed profiles found at the site in the Strait of 

 Juan de Fuca ... 23 



3.5 Chart of local area ^ East of Singapore ... 25 



3.6 Characteristic winter and summer sound speed profiles for the East of 

 Singapore site ... 26 



3.7 Chart of local area — Lands End ... 27 



3.8 Characteristic winter and summer sound speed profiles for the Lands End site ... 28 



3.9 Chart of local area — Korea Strait ... 30 



3.10 Characteristic winter and summer sound speed profiles for the Korea Strait 

 site. The summer profile is an August profile ... 32 



3.11 Chart of local area — Straits of Sicily ... 34 



3.12 Characteristic winter and summer sound speed profiles for the site in 

 the Straits of Sicily ... 35 



4. 1 Propagation loss for optimum receiver depth vs frequency for ranges of 

 50, 100 and 150 km. North Sea winter (positive gradient) profile; 

 source depth 25 m ... 40 



4.2 Propagation loss for optimum receiver depth vs frequency for ranges of 

 50, 100 and 150 km. North Sea summer profile; source depth 25 m ... 40 



4.3 Propagation loss for optimum receiver depth vs frequency for ranges of 



50, 100 and 150 km. North Sea intermediate profile; source depth 25 m ... 41 



4.4 Propagation loss vs receiver depth for the frequencies of 150, 300 and 600 Hz; 

 North Sea summer profile; source depth 25 m ... 41 



4.5 Propagation loss vs receiver depth for the frequencies of 150, 300 and 600 Hz; 

 North Sea summer profile, source depth 90 m ... 42 



4.6 Propagation loss for optimum receiver depth vs frequency for ranges of 50, 

 100 and 150 km. Strait of Juan de Fuca winter (positive-gradient) profile; 

 source depth 25 m ... 44 



