[1] This study presents temporal variations in concentrations of chlorophyll a (Chl a), particula... more [1] This study presents temporal variations in concentrations of chlorophyll a (Chl a), particulate and dissolved dimethylsulfoniopropionate (DMSPp and DMSPd) in the sea ice and underlying water column in the Canadian Arctic Archipelago during the spring of 2010 and 2011. During both years, bottom-ice Chl a, DMSPp and DMSPd concentrations were high (up to 1328 µg L-1, 15 000 nmol L-1, and 6000 nmol L-1, respectively) in May and decreased thereafter. The release of bottom ice algae and DMSPp in the water column was gradual in 2010 and rapid (8 days) in 2011. Bottom brine drainage during the pre-snowmelt period in 2010 and a rapid loss of the snow cover in 2011 coinciding with rain events explain most of the difference between the two years. During both years, less than 13% of the DMSPd lost from the ice was detected in the water column, suggesting a rapid microbial consumption. An under-ice diatom bloom developed in both years. In 2010, the bloom was dominated by centric diatoms whil...
ABSTRACT: The downward export of organic material was assessed during the productive period (late... more ABSTRACT: The downward export of organic material was assessed during the productive period (late spring to early autumn) in the North Water polynya area (NOW; northern Baffin Bay). Freedrifting short-term particle interceptor traps were deployed at 3 depths below the ...
Proceedings of the National Academy of Sciences of the United States of America, Jun 30, 2017
Summertime Arctic shipboard observations of oxygenated volatile organic compounds (OVOCs) such as... more Summertime Arctic shipboard observations of oxygenated volatile organic compounds (OVOCs) such as organic acids, key precursors of climatically active secondary organic aerosol (SOA), are consistent with a novel source of OVOCs to the marine boundary layer via chemistry at the sea surface microlayer. Although this source has been studied in a laboratory setting, organic acid emissions from the sea surface microlayer have not previously been observed in ambient marine environments. Correlations between measurements of OVOCs, including high levels of formic acid, in the atmosphere (measured by an online high-resolution time-of-flight mass spectrometer) and dissolved organic matter in the ocean point to a marine source for the measured OVOCs. That this source is photomediated is indicated by correlations between the diurnal cycles of the OVOC measurements and solar radiation. In contrast, the OVOCs do not correlate with levels of isoprene, monoterpenes, or dimethyl sulfide. Results fro...
ABSTRACT: Newly formed sea ice was sampled at 32 stations on the Mackenzie shelf, between 30 Sept... more ABSTRACT: Newly formed sea ice was sampled at 32 stations on the Mackenzie shelf, between 30 September and 19 November 2003. At each station, sea ice and surface waters were analysed to assess the concentration and enrichment of nutrients, exopolymeric ...
A steady-state model of the planktonic food web of the Bizerte Lagoon (Tunisia, South-western Med... more A steady-state model of the planktonic food web of the Bizerte Lagoon (Tunisia, South-western Mediterranean) was developed to characterize its structure and functioning through four stations: MA under urban discharge, MB impacted by industrial input, MJ located at ...
[1] This study presents temporal variations in concentrations of chlorophyll a (Chl a), particula... more [1] This study presents temporal variations in concentrations of chlorophyll a (Chl a), particulate and dissolved dimethylsulfoniopropionate (DMSPp and DMSPd) in the sea ice and underlying water column in the Canadian Arctic Archipelago during the spring of 2010 and 2011. During both years, bottom-ice Chl a, DMSPp and DMSPd concentrations were high (up to 1328 µg L-1, 15 000 nmol L-1, and 6000 nmol L-1, respectively) in May and decreased thereafter. The release of bottom ice algae and DMSPp in the water column was gradual in 2010 and rapid (8 days) in 2011. Bottom brine drainage during the pre-snowmelt period in 2010 and a rapid loss of the snow cover in 2011 coinciding with rain events explain most of the difference between the two years. During both years, less than 13% of the DMSPd lost from the ice was detected in the water column, suggesting a rapid microbial consumption. An under-ice diatom bloom developed in both years. In 2010, the bloom was dominated by centric diatoms whil...
ABSTRACT: The downward export of organic material was assessed during the productive period (late... more ABSTRACT: The downward export of organic material was assessed during the productive period (late spring to early autumn) in the North Water polynya area (NOW; northern Baffin Bay). Freedrifting short-term particle interceptor traps were deployed at 3 depths below the ...
Proceedings of the National Academy of Sciences of the United States of America, Jun 30, 2017
Summertime Arctic shipboard observations of oxygenated volatile organic compounds (OVOCs) such as... more Summertime Arctic shipboard observations of oxygenated volatile organic compounds (OVOCs) such as organic acids, key precursors of climatically active secondary organic aerosol (SOA), are consistent with a novel source of OVOCs to the marine boundary layer via chemistry at the sea surface microlayer. Although this source has been studied in a laboratory setting, organic acid emissions from the sea surface microlayer have not previously been observed in ambient marine environments. Correlations between measurements of OVOCs, including high levels of formic acid, in the atmosphere (measured by an online high-resolution time-of-flight mass spectrometer) and dissolved organic matter in the ocean point to a marine source for the measured OVOCs. That this source is photomediated is indicated by correlations between the diurnal cycles of the OVOC measurements and solar radiation. In contrast, the OVOCs do not correlate with levels of isoprene, monoterpenes, or dimethyl sulfide. Results fro...
ABSTRACT: Newly formed sea ice was sampled at 32 stations on the Mackenzie shelf, between 30 Sept... more ABSTRACT: Newly formed sea ice was sampled at 32 stations on the Mackenzie shelf, between 30 September and 19 November 2003. At each station, sea ice and surface waters were analysed to assess the concentration and enrichment of nutrients, exopolymeric ...
A steady-state model of the planktonic food web of the Bizerte Lagoon (Tunisia, South-western Med... more A steady-state model of the planktonic food web of the Bizerte Lagoon (Tunisia, South-western Mediterranean) was developed to characterize its structure and functioning through four stations: MA under urban discharge, MB impacted by industrial input, MJ located at ...
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Papers by Michel Gosselin