[G02-P] Poster

[G02-P-16] PCA and along track filtering of Crysoat2 SSH for DOT modeling in the Mediterranean

^○Dimitrios Natsiopoulos, Georgios Vergos, Ilias Tziavos (GravLab, Department of Geodesy and Surveying, Aristotle University of Thessaloniki, Thessaloniki, GR-54124, Greece)

With the availability of an abundance of earth observation data from satellite altimetry missions, monitoring of the sea level variations is gaining increased importance. Given the availability of altimetric sea surface heights (SSHs) one can employ all such available data to estimate the mean dynamic ocean topography (DOT) as well as its time varying, part. ESA's Cryosat2 mission with its orbit characteristics, measurements mode and accuracy can be used for sea level anomaly (SLA), geoid and DOT modeling over the entire Mediterranean basin. The main goal of this work is to use the altimetry data of Cryosat2 from the mission start until the end of 2016 for the determination of the DOT for the Mediterranean Sea. To this respect, along-track filtering of the Cryosat2 SLAs, derived from the combination of the original SSHs with the GOCO05c GOCE-based Global Geopotential Model (GGM) is investigated, while through a Principal Component Analysis the structure of the data variability will be explored. Principal Component Analysis (PCA) is used to investigate the temporal spatial variations of DOT and derive annual and secular trends. For the along-track filtering, spectral filters will be examined, based on various options of FIR and IIR filters. Filtering is applied along the whole passes of the satellite in order to remove/reduce the effects of geoid omission and commission errors still remaining in the DOT due to the limited representation offered by the GGM. Finally, for the evaluation of the new filtered DOT models, the RIO_MED and SMDT synthetic models for the Mediterranean and DTU10 have been used.