@article{fdi:010090180,
  title = {{F}irst description of in situ chlorophyll fluorescence signal within {E}ast {A}ntarctic coastal polynyas during fall and winter},
  author = {{B}ourreau, {L}. and {P}authenet, {E}tienne and {L}e {S}ter, {L}. and {P}icard, {B}. and {P}ortela, {E}. and {S}allee, {J}. {B}. and {M}c{M}ahon, {C}. {R}. and {H}arcourt, {R}. and {H}indell, {M}. and {G}uinet, {C}. and {B}estley, {S}. and {C}harrassin, {J}. {B}. and {D}u{V}ivier, {A}. and {S}ylvester, {Z}. and {K}rumhardt, {K}. and {J}enouvrier, {S}. and {L}abrousse, {S}.},
  editor = {},
  language = {{ENG}},
  abstract = {{A}ntarctic coastal polynyas are persistent and recurrent regions of open water located between the coast and the drifting pack-ice. {I}n spring, they are the first polar areas to be exposed to light, leading to the development of phytoplankton blooms, making polynyas potential ecological hotspots in sea-ice regions. {K}nowledge on polynya oceanography and ecology during winter is limited due to their inaccessibility. {T}his study describes i) the first in situ chlorophyll fluorescence signal (a proxy for chlorophyll-a concentration and thus presence of phytoplankton) in polynyas between the end of summer and winter, ii) assesses whether the signal persists through time and iii) identifies its main oceanographic drivers. {T}he dataset comprises 698 profiles of fluorescence, temperature and salinity recorded by southern elephant seals in 2011, 2019-2021 in the {C}ape-{D}arnley ({CDP};67{S}-69{E}) and {S}hackleton ({SP};66{S}-95{E}) polynyas between {F}ebruary and {S}eptember. {A} significant fluorescence signal was observed until {A}pril in both polynyas. {A}n additional signal occurring at 130m depth in {A}ugust within {CDP} may result from in situ growth of phytoplankton due to potential adaptation to low irradiance or remnant chlorophyll-a that was advected into the polynya. {T}he decrease and deepening of the fluorescence signal from {F}ebruary to {A}ugust was accompanied by the deepening of the mixed layer depth and a cooling and salinification of the water column in both polynyas. {U}sing {P}rincipal {C}omponent {A}nalysis as an exploratory tool, we highlighted previously unsuspected drivers of the fluorescence signal within polynyas. {CDP} shows clear differences in biological and environmental conditions depending on topographic features with higher fluorescence in warmer and saltier waters on the shelf compared with the continental slope. {I}n {SP}, near the ice-shelf, a significant fluorescence signal in {A}pril below the mixed layer (around 130m depth), was associated with fresher and warmer waters. {W}e hypothesize that this signal could result from potential ice-shelf melting from warm water intrusions onto the shelf leading to iron supply necessary to fuel phytoplankton growth. {T}his study supports that {A}ntarctic coastal polynyas may have a key role for polar ecosystems as biologically active areas throughout the season within the sea-ice region despite inter and intra-polynya differences in environmental conditions.},
  keywords = {sea ice ; {A}ntarctic polynya ; biotelemetry ; chlorophyll-a ; {CTD} ; {ANTARCTIQUE}},
  booktitle = {},
  journal = {{F}rontiers in {M}arine {S}cience},
  volume = {10},
  numero = {},
  pages = {1186403 [17 p.]},
  year = {2023},
  DOI = {10.3389/fmars.2023.1186403},
  URL = {https://www.documentation.ird.fr/hor/fdi:010090180},
}