Publications des scientifiques de l'IRD

Para J., Charrière B., Matsuoka A., Miller W. L., Rontani J. F., Sempéré Richard. (2013). UV/PAR radiation and DOM properties in surface coastal waters of the Canadian shelf of the Beaufort Sea during summer 2009. Biogeosciences, 10 (4), p. 2761-2774. ISSN 1726-4170.

Titre du document
UV/PAR radiation and DOM properties in surface coastal waters of the Canadian shelf of the Beaufort Sea during summer 2009
Année de publication
2013
Type de document
Article référencé dans le Web of Science WOS:000318434200042
Auteurs
Para J., Charrière B., Matsuoka A., Miller W. L., Rontani J. F., Sempéré Richard
Source
Biogeosciences, 2013, 10 (4), p. 2761-2774 ISSN 1726-4170
Surface waters from the Beaufort Sea in the Arctic Ocean were evaluated for dissolved organic carbon (DOC), and optical characteristics including UV (ultraviolet) radiation and PAR (photosynthetically active radiation) diffuse attenuation (K-d), and chromophoric and fluorescent dissolved organic matter (CDOM and FDOM) as part of the MALINA field campaign (30 July to 27 August). Spectral absorption coefficients (a(CDOM) (350 nm) (m(-1))) were significantly correlated to both diffuse attenuation coefficients (K-d) in the UV-A and UV-B and to DOC concentrations. This indicates CDOM as the dominant attenuator of both UV and PAR solar radiation and suggests its use as an optical proxy for DOC concentrations in this region. While the Mackenzie input is the main driver of CDOM dynamics in low salinity waters, locally, primary production can create significant increases in CDOM. Extrapolating CDOM to DOC relationships, we estimate that similar to 16% of the DOC in the Mackenzie River does not absorb radiation at 350 nm. The discharges of DOC and its chromophoric subset (CDOM) by the Mackenzie River during the MALINA cruise are estimated as similar to 0.22 TgC and 0.18 TgC, respectively. Three dissolved fluorescent components (C1-C3) were identified by fluorescence excitation/emission matrix spectroscopy (EEMS) and parallel factor (PARAFAC) analysis. Our results showed an aquatic dissolved organic matter (DOM) component (C1), probably produced in the numerous lakes of the watershed, that co-dominated with a terrestrial humic-like component (C2) in the Mackenzie Delta Sector. This aquatic DOM could partially explain the high CDOM spectral slopes observed in the Beaufort Sea.
Plan de classement
Limnologie physique / Océanographie physique [032]
Description Géographique
CANADA ; ARCTIQUE
Localisation
Fonds IRD [F B010081602]
Identifiant IRD
PAR00010520
Contact