Title :
Hidden surface dynamical modes and SSH retrievals from a joint analysis of altimetry and microwave SST
Author :
Tandeo, Pierre ; Fablet, Ronan ; Ailliot, Pierre
Author_Institution :
Dept. Signal & Commun., Technopole Brest-Iroise, Telecom Bretagne, Brest, France
Abstract :
The availability of daily satellite Sea Surface Temperature (SST) data and theoretical results (see e.g., [1]) advocate for new methods to retrieve the Sea Surface Height (SSH) and the surface geostrophic currents from SST observations. The underlying hypothesis comes to assume that the local variations of the SST relate to the surface currents. Ocean turbulence models, such as the Surface Quasi Geostrophic (SQG) theory (cf. [2], [3]) or statistical methods like neural networks (cf. [4]) or latent class regressions (cf. [5]) provide different means to state the SST-SSH relationships. This later approach has the advantage to be completely parametric and to account for different transfer functions between SST and SSH. It relies on a conditional setting with respect to a hidden variable related to different dynamical modes at the surface of the ocean. In this paper, we aim at further developing such latent models with an emphasis on two aspects: (i) the modeling and learning of the spatio-temporal dynamics of the hidden dynamical modes using Markovian priors, (ii) the reconstruction of daily SSH fields from a joint analysis of microwave SST and altimetry observation series. We evaluate the proposed model both qualitatively and quantitatively with respect to the reference altimetry product.
Keywords :
Markov processes; altimeters; atmospheric turbulence; height measurement; microwave measurement; ocean temperature; oceanographic techniques; spatiotemporal phenomena; statistical analysis; transfer functions; Markovian priors; SSH fields reconstruction; SSH retrieval; altimetry observation series; hidden surface dynamical mode; joint analysis; latent model; microwave SST; ocean turbulence model; sea surface height; sea surface temperature; spatiotemporal dynamics; statistical method; surface geostrophic current; transfer function; Altimetry; Hidden Markov models; Microwave theory and techniques; Ocean temperature; Sea surface; Surface topography;
Conference_Titel :
Geoscience and Remote Sensing Symposium (IGARSS), 2014 IEEE International
Conference_Location :
Quebec City, QC
DOI :
10.1109/IGARSS.2014.6947650