Super-resolution of satellite-derived SST data via Generative Adversarial Networks

TL;DR

This paper explores the use of deep generative models, specifically C-GANs, to improve the super-resolution of satellite-derived sea surface temperature data, capturing fine-scale ocean features better than traditional methods.

Contribution

It introduces a novel application of C-GANs for SST super-resolution, demonstrating improved statistical realism over autoencoders in reconstructing high-frequency ocean features.

Findings

C-GANs effectively restore high-frequency SST variability.

Autoencoders reduce reconstruction error but miss fine-scale features.

Deep generative models enhance the realism of satellite SST data.

Abstract

In this work, we address the super-resolution problem of satellite-derived sea surface temperature (SST) using deep generative models. Although standard gap-filling techniques are effective in producing spatially complete datasets, they inherently smooth out fine-scale features that may be critical for a better understanding of the ocean dynamics. We investigate the use of deep learning models as Autoencoders (AEs) and generative models as Conditional-Generative Adversarial Networks (C-GANs), to reconstruct small-scale structures lost during interpolation. Our supervised -- model free -- training is based on SST observations of the Mediterranean Sea, with a focus on learning the conditional distribution of high-resolution fields given their low-resolution counterparts. We apply a tiling and merging strategy to deal with limited observational coverage and to ensure spatial continuity. Quantitative evaluations based on mean squared error metrics, spectral analysis, and gradient statistics show that while the AE reduces reconstruction error, it fails to recover high-frequency variability. In contrast, the C-GAN effectively restores the statistical properties of the true SST field at the cost of increasing the pointwise discrepancy with the ground truth observation. Our results highlight the potential of deep generative models to enhance the physical and statistical realism of gap-filled satellite data in oceanographic applications.