Light absorption and partitioning in Arctic Ocean surface waters: impact of multiyear ice melting
Ice melting in the Arctic Ocean exposes the surface water to more radiative energy with poorly understood effects on photo-biogeochemical processes and heat deposition in the upper ocean. In August 2009, we documented the vertical variability of light absorbing components at 37 stations located in t...
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ftcopernicus:oai:publications.copernicus.org:bg18677 2023-05-15T15:00:38+02:00 Light absorption and partitioning in Arctic Ocean surface waters: impact of multiyear ice melting Bélanger, S. Cizmeli, S. A. Ehn, J. Matsuoka, A. Doxaran, D. Hooker, S. Babin, M. 2018-09-27 application/pdf https://doi.org/10.5194/bg-10-6433-2013 https://www.biogeosciences.net/10/6433/2013/ eng eng doi:10.5194/bg-10-6433-2013 https://www.biogeosciences.net/10/6433/2013/ eISSN: 1726-4189 Text 2018 ftcopernicus https://doi.org/10.5194/bg-10-6433-2013 2019-12-24T09:54:59Z Ice melting in the Arctic Ocean exposes the surface water to more radiative energy with poorly understood effects on photo-biogeochemical processes and heat deposition in the upper ocean. In August 2009, we documented the vertical variability of light absorbing components at 37 stations located in the southeastern Beaufort Sea including both Mackenzie River-influenced waters and polar mixed layer waters. We found that melting multiyear ice released significant amount of non-algal particulates (NAP) near the sea surface relative to subsurface waters. NAP absorption coefficients at 440 nm ( a NAP (440)) immediately below the sea surface were on average 3-fold (up to 10-fold) higher compared to subsurface values measured at 2–3 m depth. The impact of this unusual feature on the light transmission and remote sensing reflectance ( R rs ) was further examined using a radiative transfer model. A 10-fold particle enrichment homogeneously distributed in the first meter of the water column slightly reduced photosynthetically available and usable radiation (PAR and PUR) by ∼6 and ∼8%, respectively, relative to a fully homogenous water column with low particle concentration. In terms of R rs , the particle enrichment significantly flattered the spectrum by reducing the R rs by up to 20% in the blue-green spectral region (400–550 nm). These results highlight the impact of meltwater on the concentration of particles at sea surface, and the need for considering non-uniform vertical distribution of particles in such systems when interpreting remotely sensed ocean color. Spectral slope of a NAP spectra calculated in the UV (ultraviolet) domain decreased with depth suggesting that this parameter is sensitive to detritus composition and/or diagenesis state (e.g., POM (particulate organic matter) photobleaching). Text Arctic Arctic Ocean Beaufort Sea Mackenzie river Copernicus Publications: E-Journals Arctic Arctic Ocean Mackenzie River Biogeosciences 10 10 6433 6452 |
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Copernicus Publications: E-Journals |
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ftcopernicus |
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English |
description |
Ice melting in the Arctic Ocean exposes the surface water to more radiative energy with poorly understood effects on photo-biogeochemical processes and heat deposition in the upper ocean. In August 2009, we documented the vertical variability of light absorbing components at 37 stations located in the southeastern Beaufort Sea including both Mackenzie River-influenced waters and polar mixed layer waters. We found that melting multiyear ice released significant amount of non-algal particulates (NAP) near the sea surface relative to subsurface waters. NAP absorption coefficients at 440 nm ( a NAP (440)) immediately below the sea surface were on average 3-fold (up to 10-fold) higher compared to subsurface values measured at 2–3 m depth. The impact of this unusual feature on the light transmission and remote sensing reflectance ( R rs ) was further examined using a radiative transfer model. A 10-fold particle enrichment homogeneously distributed in the first meter of the water column slightly reduced photosynthetically available and usable radiation (PAR and PUR) by ∼6 and ∼8%, respectively, relative to a fully homogenous water column with low particle concentration. In terms of R rs , the particle enrichment significantly flattered the spectrum by reducing the R rs by up to 20% in the blue-green spectral region (400–550 nm). These results highlight the impact of meltwater on the concentration of particles at sea surface, and the need for considering non-uniform vertical distribution of particles in such systems when interpreting remotely sensed ocean color. Spectral slope of a NAP spectra calculated in the UV (ultraviolet) domain decreased with depth suggesting that this parameter is sensitive to detritus composition and/or diagenesis state (e.g., POM (particulate organic matter) photobleaching). |
format |
Text |
author |
Bélanger, S. Cizmeli, S. A. Ehn, J. Matsuoka, A. Doxaran, D. Hooker, S. Babin, M. |
spellingShingle |
Bélanger, S. Cizmeli, S. A. Ehn, J. Matsuoka, A. Doxaran, D. Hooker, S. Babin, M. Light absorption and partitioning in Arctic Ocean surface waters: impact of multiyear ice melting |
author_facet |
Bélanger, S. Cizmeli, S. A. Ehn, J. Matsuoka, A. Doxaran, D. Hooker, S. Babin, M. |
author_sort |
Bélanger, S. |
title |
Light absorption and partitioning in Arctic Ocean surface waters: impact of multiyear ice melting |
title_short |
Light absorption and partitioning in Arctic Ocean surface waters: impact of multiyear ice melting |
title_full |
Light absorption and partitioning in Arctic Ocean surface waters: impact of multiyear ice melting |
title_fullStr |
Light absorption and partitioning in Arctic Ocean surface waters: impact of multiyear ice melting |
title_full_unstemmed |
Light absorption and partitioning in Arctic Ocean surface waters: impact of multiyear ice melting |
title_sort |
light absorption and partitioning in arctic ocean surface waters: impact of multiyear ice melting |
publishDate |
2018 |
url |
https://doi.org/10.5194/bg-10-6433-2013 https://www.biogeosciences.net/10/6433/2013/ |
geographic |
Arctic Arctic Ocean Mackenzie River |
geographic_facet |
Arctic Arctic Ocean Mackenzie River |
genre |
Arctic Arctic Ocean Beaufort Sea Mackenzie river |
genre_facet |
Arctic Arctic Ocean Beaufort Sea Mackenzie river |
op_source |
eISSN: 1726-4189 |
op_relation |
doi:10.5194/bg-10-6433-2013 https://www.biogeosciences.net/10/6433/2013/ |
op_doi |
https://doi.org/10.5194/bg-10-6433-2013 |
container_title |
Biogeosciences |
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10 |
container_issue |
10 |
container_start_page |
6433 |
op_container_end_page |
6452 |
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1766332723681558528 |