SWOT Sea Surface Height Calibration and Validation

Abstract:

The Surface Water and Ocean Topography mission (SWOT) aims to observe sea surface height (SSH) with unprecedented low instrument noise along two-dimensional swaths. It can reveal oceanic features down to 15 km over energetic regions. For these small-scale features, the amplitude of the SSH anomaly decreases dramatically to level ~ 1 cm. Measuring these small-amplitude features not only imposes stringent requirements on the satellite engineering, but also on the estimation of the ground truth for the post-launch calibration and validation (CalVal). In this talk, we will discuss the activities conducted towards building a SWOT-SSH post-launch CalVal campaign. These activities include Observational System Simulation Experiments (OSSEs) and pre-launch field campaigns. Analyses of OSSEs and observations from field campaigns point to the robustness of in-situ CTD moorings to accurately reconstruct the SSH to meet the SWOT requirement. Based on these results, we will present the baseline design of the post-launch field campaign for the SSH CalVal to be conducted after the launch of the satellite in 2022. We will also discuss opportunities of expanding our baseline campaign into a larger oceanography campaign with a broader community involvement focusing on fine-scale ocean dynamics.