Navigation geographical

The addition of salt to water increases the viscosity of water. This is caused by the electrostatic attraction between the solutes and water. Because of slight spatial differences in salinity, the viscosity, and, hence, the speed of sound in seawater is also geographically variable. This is of practical consequence because the operation of SONAR (Sound Navigation Ranging) depends on a precise knowledge of the speed of sound in seawater. As described in Chapter 1, World War II made the need for accurate SONAR essential. This demand motivated the first detailed studies of the distribution of salinity and temperature in the ocean, which marked the beginning of the modern age of oceanography. 

Cooke, Francis, The principles of geometric, astronomic, and geographic Cortes, Martin, The arte of navigation, tr. Richard Eden (1561). 

Long, Michael E. "Secrets of Animal Navigation. National Geographic 179, no. 6. (June 1991). 

The above navigation and positioning systems allow positioning within approximately 1 m and a repeatability of 1 m. This accuracy is prerequisite for the usefulness of the geographical information database system with individual targets. 

Geographical Situational Awareness (e.g. own aircraft, other aircraft, terrain features, airports, cities, waypoints, navigation fixes, position relative to designated features, path to desired location, runway and taxiway assignments, path to desired location, climb/descent points, etc.)... 

Such a device with three orthogonal Sagnac interferometers can be used as a navigation system, because the Earth s rotation causes a Sagnac effect that depends on the angle between the surface normal n and the Earth s axis of rotation > i.e., on the geographical latitude. 

Enclosed bays have always been natural environment next to urban areas, and provided us with uncountable benefits. Due to their particular geographic featm-e, the enclosed bays are stable when compared with open seas, and cannot be easily influenced by ocean weather conditions. Because of this, many harbors are located in enclosed bays, and hence many big cities in the world, even today, are located aroimd enclosed bays. Enclosed bays also provide fish and shellfish resources, and navigation and recreation potentials. In addition, the suitability of coastal zone for various human activities has led to reclamation of shallow water areas on mildly sloping bottom. ... 

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