Discerning dominant temporal patterns of bio-optical properties in the northwestern Mediterranean Sea (BOUSSOLE site)
|Author(s)||Bellacicco M.1, Vellucci V.2, D'Ortenzio F.1, Antoine D.1, 3|
|Affiliation(s)||1 : Sorbonne Univ, CNRS, LOV, F-06230 Villefranche Sur Mer, France.
2 : Sorbonne Univ, CNRS, Inst La Mer Villefranche, IMEV, F-06230 Villefranche Sur Mer, France.
3 : Curtin Univ, Sch Earth & Planetary Sci, Remote Sensing & Satellite Res Grp, Perth, WA 6845, Australia.
|Source||Deep-sea Research Part I-oceanographic Research Papers (0967-0637) (Pergamon-elsevier Science Ltd), 2019-06 , Vol. 148 , P. 12-24|
|Keyword(s)||Phenology, Bio-optical properties, Time-series analysis, Wavelet analysis|
A wavelet analysis has been applied, for the first time, to 3-year high-frequency field observations of bio-optical properties (i.e. chlorophyll-fluorescence, beam attenuation and backscattering coefficients) in the northwestern Mediterranean Sea (BOUSSOLE site), in order to identify their dominant temporal patterns and evolution. A cross-wavelet and coherence analysis has also been applied to paired bio-optical coefficients time-series at the BOUSSOLE site, which allows identifying the temporal relationship between the cycles of the bio-optical properties. Annual, six- and four-month, intra-seasonal (i.e., mid- and short-terms) cycles are identified from the time-series analysis. The periodicities of chlorophyll-fluorescence, beam attenuation and particulate back-scattering coefficients correlate well at different temporal scales and specific seasons. At annual, six- and four-month scales, different bio-optical properties follow rather similar patterns, likely driven by physical forcing. Intra-seasonal variability consists in both mid- and short-term variations. The former dominates during the winter and are related to episodic bloom events, while the latter variations (i.e., diel) prevail during summer, in a stratified water column.