Sentinel-3a Delay Doppler Processing: Assessment over the Global Ocean.

Matthias Raynal (CLS, France)

CoAuthors

Sylvie Labroue (CLS, France); Marion Orsztynowicz (CLS, France); Nicolas Picot (CNES, France); Amandine Guillot (CNES, France); François Boy (CNES, France)

Event: 2016 SAR Altimetry Workshop

Session: SAR mode performances: SAR CALVAL from Cryosat-2 and Sentinel-3

Presentation type: Type Oral

The ESA (European Space Agency) mission Sentinel-3a was successfully launched in February 2016. Sentinel-3a is a multi-instrument mission to measure sea-surface topography, sea- and land-surface temperature, ocean colour and land colour with high-end accuracy and reliability. The mission will support ocean forecasting systems, as well as environmental and climate monitoring.
As the Cryosat-2 altimeter, the SRAL (Sentinel Radar Altimeter) radar differs from previous conventional pulse limited altimeter in that it is capable of operating in several modes. The conventional or low resolution mode (LRM) was activated during the first cycle in order to ensure the continuity with the Synthetic Aperture Radar mode (SARM) activated since the 12th April 2016 over the global Ocean.
The SARM (or Delay Doppler mode) full coverage is available for the first time in the altimetry history and it will allow to strengthen the past results obtained with Cryosat-2 and to better characterise the SARM benefits (noise reduction, smaller across-track footprint) using a more representative sampling and taking into account the regional specificities.
The Sentinel-3a Prototype Processing (S3PP) developed by CNES (Boy et al., 2015-2016) inherited from the Cryosat-2 Prototype Processing (CPP) (Boy et al., 2012-2013) starts from Sentinel-3a level-0 telemetry files and generate Sea Level Anomaly (SLA) measures for each record in LRM or SAR mode. The present study shows some results obtained with a half year of S3PP Delay Doppler data record. Data quality has been assessed through different metrics that are presented here. We analyse more deeply the main features to check the reliability and the improvements of the SARM processing (noise reduction, increased along track spatial resolution, check of the dependencies that may induce geographically correlated errors ...).
 

Oral presentation show times:

RoomStart DateEnd Date
Auditorium Mon, Oct 31 2016,14:00 Mon, Oct 31 2016,14:15
Matthias Raynal
CLS
France
mraynal@cls.fr