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THE USE OF GRAVITY FOR GIS DATA SETS OPTIMIZATION. 
I.A.Maslov. General Physics Institute 
R.A.S., Moscow. RUSSIA 
Comission III 
KEY WORDS: GIS,Oceanology,Gravity,Knowledge Base. 
ABSTRACT 
It has been increasingly recognised that measurement of sea surface topography is of 
the fundamental importance to a wide range of research in 
climatology,oceanography,geology and geodesy. In order to explore information about 
local changes of state is important to know the fields and processes governs and 
accompanied such a phenomena .To improve the understanding of the state variables 
processes for the exploration of environmental changes time-series data usual comprise 
the successive control points or areas. Relationship between the ocean movements and 
marine geoid for different scales of events are discussed.It is shown that the water 
flows,e.i.sea surface topography, and gravity anomalies are interrelated.This results 
indicate the usefulness of the marine gravity for an optimum spatial environmental 
sampling strategies. 
INTRODUCTION 
Oceanographers describe the motion and thermodynamics of the ocean by use the 
equation of motion,also called Navier-Stokes equations. According to Newton's second 
law mass times acceleration is equal to the sum of forces acting on the mass.For a 
volume of fluid Newton's law is divided by the mass per volume,the density $ ,and 
written as an equation for acceleration : the acceleration due to gravity, g, the pressure, 
p . gradient,the Coriolis acceleration ,fv,and the acceleration due to friction, 
To a certain degree of approximation idealised sea surface coincides with mean sea 
level,i.e. reference ellipsoid. The equation of motion contain the acceleration due to 
gravity,g,which means only directed along a normal to the earth's reference ellipsoid. 
In large-scale flow the vertical accelerations are small in the sense that it can be 
neglected against g. Hence, the vertical component of the Navier-Stokes equations 
reduces to the hydrostatic equation: ¢pfz =-g3. (141) 
In many cases the simplest type of equilibrium flow is balance of the pressure gradient 
and the Coriolis accelerations: 
u,7-l/sfgp&y, vy = 15£2p/x. (2) 
The factor f 2 22sinc', where Ç is latitude 
and rotation rate of the earth,is called the Coriolis parameter. 
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International Archives of Photogrammetry and Remote Sensing. Vol. XXXI, Part B3. Vienna 1996