stands about 60 cm higher than along the Atlantic coast, 

 as shown in Figure 4. 



Montgomery (1969) has concluded that the oceanographic 

 results are in good agreement with the leveling results 

 as to the difference in mean sea level between the Atlantic 

 coast and the Pacific coast of the United States. The 

 oceanographic leveling here suffers from the problem of 

 a reference-level assumption, and I have recently estimated 

 (Sturges, 1971) that the uncertainty introduced by the 

 choice of a reference surface is only a few centimeters. 



A question that remains unresolved, however , is the 

 apparent slope from south to north as indicated by the 

 leveling results. A slope of 60 cm is a very large signal 

 in terms of ocean currents, so the apparent slope along 

 the coasts is important, in terms of ocean circulation. 



The oceanographic result refutes this coastal slope 

 (Sturges, 1967). That is, oceanographically, we expect 

 sea level at San Diego to be some 9 cm higher than at 

 Neah Bay. The leveling results are from a combination of 

 a very large number of short sights. It is possible, 

 therefore, that the presence of an extremely small undetected 

 systematic leveling error in the north- south direction 

 could contribute to a resulting systematic error in the 

 leveling results. The only definite statement we can make 

 is that the two results do not agree. It might be possible 

 to resolve this discrepancy by searching for the systematic 

 error in the leveling results. But the satellite altimetry 

 program offers the promise of being able to determine 

 whether the coastal slopes exist, by an independent method. 



This problem is a thorny one in terms of separating 

 a slope of the Geoid from a slope of the sea surface. This 

 aspect of the problem could be side-stepped by using the 

 basic oceanographic results in deep water (as discussed 

 above, concerning Stommel's map). The satellite results 

 could be used only to connect the coastal points to the 



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