A Method of Unifying the Global Crustal Vertical Motion Reference Datum

Objective One method for taking SLR as the global crustal vertical motion reference datum is proposedafter considering SLR ranging characteristics.The data for coordinates and velocity fields that SLR,GNSS and VLBI analysis centers submitted to the ITRF2008and ITRF2005was used to select highprecision co-location sites and calculate their vertical velocity field in the local coordinate system usingcoordinate conversion.Systematic errors between SLR and GNSS or VLBI vertical velocity field werecalculated based on a deduced mathematical model.With the calculated systematic errors,the verticalvelocity fields of GNSS and VLBI were corrected to the SLR vertical motion reference datum.TakingSLR as the global crustal vertical motion reference datum was proven to be feasible as the correlationcoefficient as the slope tends to be 1after consistency inspection.