Distribution and recurrence of phytoplankton blooms around South Georgia, Southern Ocean
South Georgia phytoplankton blooms are amongst the largest of the Southern Ocean and are associated with a rich ecosystem and strong atmospheric carbon drawdown. Both aspects depend on the intensity of blooms, but also on their regularity. Here we use data from 12 yr of SeaWiFS (Sea-viewing Wide Fie...
Published in: | Biogeosciences |
---|---|
Main Authors: | , |
Format: | Other/Unknown Material |
Language: | English |
Published: |
2018
|
Subjects: | |
Online Access: | https://doi.org/10.5194/bg-10-217-2013 https://www.biogeosciences.net/10/217/2013/ |
id |
ftcopernicus:oai:publications.copernicus.org:bg16368 |
---|---|
record_format |
openpolar |
spelling |
ftcopernicus:oai:publications.copernicus.org:bg16368 2023-05-15T18:25:09+02:00 Distribution and recurrence of phytoplankton blooms around South Georgia, Southern Ocean Borrione, I. Schlitzer, R. 2018-09-27 info:eu-repo/semantics/application/pdf https://doi.org/10.5194/bg-10-217-2013 https://www.biogeosciences.net/10/217/2013/ eng eng info:eu-repo/grantAgreement/EC/FP7/264879 doi:10.5194/bg-10-217-2013 https://www.biogeosciences.net/10/217/2013/ info:eu-repo/semantics/openAccess eISSN: 1726-4189 info:eu-repo/semantics/Text 2018 ftcopernicus https://doi.org/10.5194/bg-10-217-2013 2019-12-24T09:55:38Z South Georgia phytoplankton blooms are amongst the largest of the Southern Ocean and are associated with a rich ecosystem and strong atmospheric carbon drawdown. Both aspects depend on the intensity of blooms, but also on their regularity. Here we use data from 12 yr of SeaWiFS (Sea-viewing Wide Field-of-view Sensor) ocean colour imagery and calculate the frequency of bloom occurrence (FBO) to re-examine spatial and temporal bloom distributions. We find that upstream of the island and outside the borders of the Georgia Basin, blooms occurred in less than 4 out of the 12 yr (FBO < 4). In contrast, FBO was mostly greater than 8 downstream of the island, i.e., to the north and northwest, and in places equal to 12, indicating that blooms occurred every year. The typical bloom area, defined as the region where blooms occurred in at least 8 out of the 12 yr, covers the entire Georgia Basin and the northern shelf of the island. The time series of surface chlorophyll a (Chl a ) concentrations averaged over the typical bloom area shows that phytoplankton blooms occurred in every year between September 1997 and September 2010, and that Chl a values followed a clear seasonal cycle, with concentration peaks around December followed in many years by a second peak during late austral summer or early autumn, suggesting a bi-modal bloom pattern. The bloom regularity we describe here is in contrast with results of Park et al. (2010) who used a significantly different study area including regions that almost never exhibit bloom conditions. Other/Unknown Material Southern Ocean Copernicus Publications: E-Journals Austral Georgia Basin ENVELOPE(-35.500,-35.500,-50.750,-50.750) Southern Ocean Biogeosciences 10 1 217 231 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
South Georgia phytoplankton blooms are amongst the largest of the Southern Ocean and are associated with a rich ecosystem and strong atmospheric carbon drawdown. Both aspects depend on the intensity of blooms, but also on their regularity. Here we use data from 12 yr of SeaWiFS (Sea-viewing Wide Field-of-view Sensor) ocean colour imagery and calculate the frequency of bloom occurrence (FBO) to re-examine spatial and temporal bloom distributions. We find that upstream of the island and outside the borders of the Georgia Basin, blooms occurred in less than 4 out of the 12 yr (FBO < 4). In contrast, FBO was mostly greater than 8 downstream of the island, i.e., to the north and northwest, and in places equal to 12, indicating that blooms occurred every year. The typical bloom area, defined as the region where blooms occurred in at least 8 out of the 12 yr, covers the entire Georgia Basin and the northern shelf of the island. The time series of surface chlorophyll a (Chl a ) concentrations averaged over the typical bloom area shows that phytoplankton blooms occurred in every year between September 1997 and September 2010, and that Chl a values followed a clear seasonal cycle, with concentration peaks around December followed in many years by a second peak during late austral summer or early autumn, suggesting a bi-modal bloom pattern. The bloom regularity we describe here is in contrast with results of Park et al. (2010) who used a significantly different study area including regions that almost never exhibit bloom conditions. |
format |
Other/Unknown Material |
author |
Borrione, I. Schlitzer, R. |
spellingShingle |
Borrione, I. Schlitzer, R. Distribution and recurrence of phytoplankton blooms around South Georgia, Southern Ocean |
author_facet |
Borrione, I. Schlitzer, R. |
author_sort |
Borrione, I. |
title |
Distribution and recurrence of phytoplankton blooms around South Georgia, Southern Ocean |
title_short |
Distribution and recurrence of phytoplankton blooms around South Georgia, Southern Ocean |
title_full |
Distribution and recurrence of phytoplankton blooms around South Georgia, Southern Ocean |
title_fullStr |
Distribution and recurrence of phytoplankton blooms around South Georgia, Southern Ocean |
title_full_unstemmed |
Distribution and recurrence of phytoplankton blooms around South Georgia, Southern Ocean |
title_sort |
distribution and recurrence of phytoplankton blooms around south georgia, southern ocean |
publishDate |
2018 |
url |
https://doi.org/10.5194/bg-10-217-2013 https://www.biogeosciences.net/10/217/2013/ |
long_lat |
ENVELOPE(-35.500,-35.500,-50.750,-50.750) |
geographic |
Austral Georgia Basin Southern Ocean |
geographic_facet |
Austral Georgia Basin Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
eISSN: 1726-4189 |
op_relation |
info:eu-repo/grantAgreement/EC/FP7/264879 doi:10.5194/bg-10-217-2013 https://www.biogeosciences.net/10/217/2013/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/bg-10-217-2013 |
container_title |
Biogeosciences |
container_volume |
10 |
container_issue |
1 |
container_start_page |
217 |
op_container_end_page |
231 |
_version_ |
1766206395285241856 |