OCEANOGRAPHY IN THE UNITED STATES 133 



be predicted, weather conditions must be predicted, gravity and mag- 

 netic conditions must be known, beach conditions, and the land areas 

 around these seas must be known. 



Specific areas of military operations affected by the oceans are : 



(a) Antisubmarine warfare. 



(b) Mine warfare. 



(c) Amphibious operations. 



(d) Offensive submarine operations. 



(e) Surface ship operations. 



I would like to comment briefly on each of these. 



The ASW problem can be clearly defined as the detection, identifi- 

 cation, and destruction of the enemy submarine. In all three of 

 these areas the oceans act in favor of the submarine. For example, 

 with the exception of the transmission of sound, the oceans are nearly 

 opaque to the transmission of all forms of energy. Even the sound 

 transmission is distorted, reflected, scattered, and absorbed by environ- 

 mental conditions such as temperature differences, chemical properties, 

 marine life, sea surface conditions, and the nature of the sea floor. 

 All systems of detecting submarines including airborne, surface ship, 

 submarine, and fixed installations must take these vagaries of the sea 

 into consideration. 



Once a target is detected there still remains a problem of identi- 

 fying it as an enemy submarine. False contacts such as whales, 

 schools of fish, and abnormal sound conditions have to be minimized. 

 These environmental problems are being investigated. After the 

 target is detected and identified the oceans still protect it from any 

 weapons system. 



In mine warfare, we find that marine animals foul our mines to an 

 extent that the mines eventually become inoperative. Bottom sedi- 

 ments may bury mines and unknown oceanic currents may sweep them 

 away. In many cases, the design of the triggering mechanism is 

 complicated by the fact that oceanic environment exhibits properties 

 that are similar to those properties of ships that trigger mines. In 

 mine warfare countermeasures we find that the ocean again interferes 

 with our ability to detect mines, so that often our first notice of a 

 minefield is the destruction of one of our own ships. 



Our World War II experience illustrated the necessity of being able 

 to predict ocean waves and surf as well as having a knowledge of 

 beach conditions for amphibious assaults. Fundamental research on 

 ocean waves has resulted in the publication of a prediction manual 

 which is currently in use by the fleet. 



There are two aspects to our offensive submarine warfare — one in- 

 volving the missile carrying submarine of the POLARIS type, the 

 other being the more conventional use of the submarine. In both 

 cases, the true submersible requires a precise method of navigation 

 while remaining imderwater. Ocean currents, bottom topography, 

 magnetic an gravitational fields are all important in this respect. 

 Surface currents and sea state conditions are also important to the 

 POLARIS submarine and we must be able to predict these with suffi- 

 cient accuracy. A knowledge of ambient noise conditions, bottom 

 topography, and the thermal structure is useful for evasive tactics. 



For surface ship operations, we must know about the weather and 

 sea surface conditions. The Hydrographic Office has been predicting 



