SP-345 Evolution of the Solar System

 

FIGURE 9.4.1a.- Phase relations of tides in the Pacific and Atlantic oceans.

FIGURE 9.4.1a.- Phase relations of tides in the Pacific and Atlantic oceans. The map shows the cotidal lines of the semidiurnal tide referred to the culmination of the Moon in Greenwich. The tidal amplitude approaches zero where the cotidal lines run parallel (such as between Japan and New Guinea). Much of the tidal motion has the character of rotary waves. In the south and equatorial Atlantic Ocean the tide mainly takes the form of north-south oscillation on east-west lines. This complex reality should be compared to the simple concept which is the basis for existing calculations of the lunar orbital evolution and which pictures the tide as a sinusoidal wave progressing around the Earth in the easterly direction (dot-and-dashed curve in fig. 9.4.1b). (From Defant, 1961.)

 
- Back -