Reduction of the gravity vertical gradients to a spherical surface

2014;
: pp. 48 - 53
Received: February 21, 2014
Accepted: March 24, 2014
1
Department of Higher Geodesy and Astronomy, Lviv Polytechnic National University
2
Lviv Polytechnic National University

The GOCE mission has produced gravity gradient data during 2009–2013 years. Various data sets were obtained, such as: tensor of second derivatives in different systems, satellite orbit parameters, the models of the gravitational field of the Earth. In contrast to the direct approach, space-wise-approach, and time-wise approach the construction of the spherical grid of gradients were orthogonality relationships are carry out, was developed via upward/downward continuation to sphere. This paper considers the vertical gravity gradients zz V (EGG TRF2 [Gruber Th., 2010]) in particular. The data sets are oriented in LNOF (Local North Oriented Frame) along the satellites track. On the following step the gravity gradients are reduced to the spherical surface and regular grid a built for for further processing. Reduction of gradients to the sphere is very important step in processing of these data. For example gravity anomalies, also, are related to the sphere. This paper considers way of reduction of gradients, using a Taylor’s series. The article performs experimental calculating and illustrated the corresponding results. The advantages of reduced gradients are demonstrated. Paper gives some recommendations in the application of EGM2008 for calculating of necessary corrections.

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