Per Knudsen (DTU Space - Denmark, Denmark); Lars Stenseng (DTU Space, Denmark)

We outline the new DTU18MSS mean sea surface which is the latest release of the global high resolution mean sea surface from DTU Space. The major new advance leading up to the release of this DTU18MSS the use of 3 years of Sentinel-3A and an improved 7 years Cryosat-2 LRM record. A new processing chain with updated editing and data correction (i.e., using FES2014 as Ocean tide model) has been implemented. The use of consistent ocean tide model for the Mean sea surface and the subsequent processing of sun-syncronous satelliites has proven to be important to reduce the error that the MSS contributes to the total error budget. The presentation will also also focus on the difficult issues as consolidating Cryosat-2 and Sentinel-3 onto a past 20 year mean sea surface derived using multiple LRM satellites as well as the importance of merging Cryosat-2 data from different operating modes like LRM, SAR and SAR-In as these requires different retrackers.