Apparent optical properties of the Canadian Beaufort Sea - Part 1: Observational overview and water column relationships
MetadataShow full item record
A data set of radiometric measurements collected in the Beaufort Sea (Canadian Arctic) in August 2009 (Malina project) is analyzed in order to describe apparent optical properties (AOPs) in this sea, which has been subject to dramatic environmental changes for several decades. The two properties derived from the measurements are the spectral diffuse attenuation coefficient for downward irradiance, Kd, and the spectral remote sensing reflectance, Rrs. The former controls light propagation in the upper water column. The latter determines how light is backscattered out of the water and becomes eventually observable from a satellite ocean color sensor. The data set includes offshore clear waters of the Beaufort Basin as well as highly turbid waters of the Mackenzie River plumes. In the clear waters, we show Kd values that are much larger in the ultraviolet and blue parts of the spectrum than what could be anticipated considering the chlorophyll concentration. A larger contribution of absorption by colored dissolved organic matter (CDOM) is responsible for these high Kd values, as compared to other oligotrophic areas. In turbid waters, attenuation reaches extremely high values, driven by high loads of particulate materials and also by a large CDOM content. In these two extreme types of waters, current satellite chlorophyll algorithms fail. This questions the role of ocean color remote sensing in the Arctic when Rrs from only the blue and green bands are used. Therefore, other parts of the spectrum (e.g., the red) should be explored if one aims at quantifying interannual changes in chlorophyll in the Arctic from space. The very peculiar AOPs in the Beaufort Sea also advocate for developing specific light propagation models when attempting to predict light availability for photosynthesis at depth.
This article is published under the Open Access publishing model and distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0/. Please refer to the licence to obtain terms for any further reuse or distribution of this work.
Showing items related by title, author, creator and subject.
Refining the chronostratigraphy of the Karoo Basin, South Africa: Magnetostratigraphic constraints support an early Permian age for the Ecca GroupBelica, M.; Tohver, E.; Poyatos-Moré, M.; Flint, S.; Parra-Avila, L.; Lanci, L.; Denyszyn, S.; Pisarevskiy, Sergei (2017)© The Authors 2017. The Beaufort Group of the Karoo Basin, South Africa provides an important chrono- and biostratigraphic record of vertebrate turnovers that have been attributed to the end-Permian mass extinction events ...
Recreating the shading effects of ship wake induced turbidity to test acclimation responses in the seagrass Thalassia hemprichiiBrowne, Nicola; Yaakub, S.; Tay, J.; Todd, P. (2017)Elevated sediment delivery and resuspension in coastal waters from human activities such as shipping can have detrimental effects on seagrass health by limiting light penetration. Managing seagrasses requires knowledge ...
The apparent paradox of abundant foramol facies in low latitudes: their environmental significance and effect on platform developmentWilson, Moyra; Vecsei, A. (2005)Recent studies of low-latitude carbonates from SE Asia and Australia have revealed deposits and platform-types that do not fit easily into the perceived view of dwarm-waterT tropical carbonates. The sediments are classified ...