This Level 2 product provides marine reflectances from the VENµS mission, processed with the Polymer algorithm, on a subset of sites with coastal or inland areas.

VENµS (Vegetation and Environment monitoring on a New Micro-Satellite) is a Franco-Israeli satellite launched in 2017, dedicated to the fine and regular monitoring of terrestrial vegetation, in particular cultivated areas, forests, protected natural areas, etc. The images acquired in 12 spectral bands by a camera provided by CNES, on a selection of about one hundred scientific sites spread over the planet, are of high spatial (5 m) and temporal resolution. The lifetime of the VENµS satellite has been divided into two phases: a first phase VM1 at an altitude of 720 km with a 2-day revisit, a native spatial resolution of 5.3 m and a swath of 27.6 km from August 2017 to November 2020, and a second phase VM5 at an altitude of 560 km with a daily revisit, a native spatial resolution of 4.1 m and a swath of 21.3 km from March 2022 to July 2024.

VENµS is the first sensor on board an orbiting satellite to combine such revisit frequency and spatial finesse for vegetation monitoring.

A subset of sites with coastal areas or inland waters have been identified to generate Level 2 data dedicated to marine reflectance. The geographical areas covered are given through a kmz file, see below to download it.

This Level 2 data product has been processed using the Polymer algorithm developed by Hygeos (https://hygeos.com/en/polymer/) and provides marine reflectances for the VENµS bands from 420 to 865 nm. These reflectances, without units, include a bidirectional normalization for the Sun at nadir and the observer at nadir.

VENµS data products (Level-1, Level-2 and Level-3) are primarily generated with the MAJA algorithm, further information can be found on THEIA website: https://www.theia-land.fr/en/product/venus/

References

- Dick, A., Raynaud, J.-L., Rolland, A., Pelou, S., Coustance, S., Dedieu, G., Hagolle, O., Burochin, J.-P., Binet, R., Moreau, A., 2022. VENμS: Mission Characteristics, Final Evaluation of the First Phase and Data Production. Remote Sensing 14, 3281. https://doi.org/10.3390/rs14143281

- Steinmetz, F., Deschamps, P.-Y., Ramon, D., 2011. Atmospheric correction in presence of sun glint: application to MERIS. Optics Express 19, 9783–9800. https://doi.org/10.1364/OE.19.009783

- Steinmetz, F., Ramon, D., 2018. Sentinel-2 MSI and Sentinel-3 OLCI consistent ocean colour products using POLYMER, in: SPIE Asia-Pacific Remote Sensing Proceedings. https://doi.org/10.1117/12.2500232

- Cox, C., Munk, W., 1954. Measurement of the Roughness of the Sea Surface from Photographs of the Sun’s Glitter. J. Opt. Soc. Am. 44, 838. https://doi.org/10.1364/JOSA.44.000838