Since ESA released to the public domain the first Global Geopotential Model (GGM) based on GOCE satellite mission data, an extensive validation/evaluation of those models has been conducted worldwide to assess their accuracy. The paper provides an accuracy assessment of 1st - 5th release GOCE-based GGMs developed with the use of the direct solution and the time-wise solution strategies over the area of Poland.
Free-air gravity anomalies and height anomalies computed from those GGMs have been compared with the corresponding ones obtained from EGM08. Moreover, height anomalies determined from GOCEbased GGMs were compared with the corresponding ones obtained from three different GNSS/levelling data sets with the use of the spectral enhancement method. The results obtained reveal clear improvement for the consecutive releases of GOCE-based GGMs investigated. The 5th release GOCE-based GGM developed with the use of time-wise strategy shows the best performance. Its fit over the area of Poland to the terrestrial data in terms of the standard deviation is 0.84 mGal for gravity anomalies and in the range of 2.8 - 3.4 cm for height anomalies.