Abstract's details
Arctic Altimetric Sea Level Cross-Validation of IceSat-2, SARAL/AltiKa, Sentinel-3 and CryoSat-2
Event: 2019 Ocean Surface Topography Science Team Meeting
Session: Science IV: Altimetry for Cryosphere and Hydrology
Presentation type: Type Poster
Contribution: not provided
Abstract:
Determining sea level variation and trends in the Arctic is still in uncertain large areas. Contamination from sea-ice makes it impossible to have a full spatial and temporal data coverage. With launch of IceSat-2 (IS2) in October 2018, IS2 is the only second satellite after CryoSat-2 (CS2) to cover the entire Arctic area (up to 88N). Together with Sentinel-3A/B and SARAL, four different satellite altimetry systems are covering the Arctic.
The four data sources are complementary in the sense that IS2 is a photon-based product where as C2, Sentinel-3 and SARAL are radar altimeters employing different frequencies (Ka vs Ku band) and different technologies. SARAL is a conventional altimeter with a pulse radar frequency (PRF) of 4000 hz whereas Sentinel-3 and C2 have SAR altimeters (C2 with SARin in selected coastal regions incl Svalbard) with an efficient PRF close to 600 Hz.
In this presentation we can validate the SSH recovery in the northernmost Atlantic Ocean close to Svalbard, which is also a location of one of the few accessible Arctic Ocean tide gauge with an associated GPS receiver. It is a region where we have data from the first months of IS2, Sentinel-3 (SAR altimetry), C2 (SAR-In altimetry) and Saral/AltiKa (conventional LRM altimetry). We will also look at cross arctic data availability and looking into the sea level budget equation, SSH = Steric + Mass. A gridded steric product (DTUSteric) based on Arctic in-situ data is used together with latest released GRACE-FO Ocean Bottom Pressure (OBP) estimates.
The four data sources are complementary in the sense that IS2 is a photon-based product where as C2, Sentinel-3 and SARAL are radar altimeters employing different frequencies (Ka vs Ku band) and different technologies. SARAL is a conventional altimeter with a pulse radar frequency (PRF) of 4000 hz whereas Sentinel-3 and C2 have SAR altimeters (C2 with SARin in selected coastal regions incl Svalbard) with an efficient PRF close to 600 Hz.
In this presentation we can validate the SSH recovery in the northernmost Atlantic Ocean close to Svalbard, which is also a location of one of the few accessible Arctic Ocean tide gauge with an associated GPS receiver. It is a region where we have data from the first months of IS2, Sentinel-3 (SAR altimetry), C2 (SAR-In altimetry) and Saral/AltiKa (conventional LRM altimetry). We will also look at cross arctic data availability and looking into the sea level budget equation, SSH = Steric + Mass. A gridded steric product (DTUSteric) based on Arctic in-situ data is used together with latest released GRACE-FO Ocean Bottom Pressure (OBP) estimates.