RTC and density variations in the estimation of local geoids

In the frame of a project aiming to the revision of the estimation procedures for local geoids, we have been studying the algorithms for the RTC systematically. In this contribution, the work carried out on a small DTM test case (5 Km x 5 Km) is presented; the work focuses especially on two topics: verifying the effect of the surface density variations ( continuous as well as discontinuous) on the computation of the RTC term and evaluating the errors introduced in the RTC computation by alternative approximations applied to the density variations modeling.