Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean
The spring bloom dominates the annual cycle of phytoplankton abundance in large regions of the world oceans. The mechanisms that trigger blooms have been studied for decades, but are still keenly debated, due in part to a lack of data on phytoplankton stocks in winter and early spring. Now however a...
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ftnerc:oai:nora.nerc.ac.uk:525895 2023-05-15T17:31:04+02:00 Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean Rumyantseva, Anna Henson, Stephanie Martin, Adrian Thompson, Andrew F. Damerell, Gillian M. Kaiser, Jan Heywood, Karen J. 2019-10-10 text http://nora.nerc.ac.uk/id/eprint/525895/ https://nora.nerc.ac.uk/id/eprint/525895/1/untitled.pdf https://doi.org/10.1016/j.pocean.2019.102202 en eng https://nora.nerc.ac.uk/id/eprint/525895/1/untitled.pdf Rumyantseva, Anna; Henson, Stephanie orcid:0000-0002-3875-6802 Martin, Adrian orcid:0000-0002-1202-8612 Thompson, Andrew F.; Damerell, Gillian M.; Kaiser, Jan; Heywood, Karen J. 2019 Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean. Progress in Oceanography, 178. 102202. https://doi.org/10.1016/j.pocean.2019.102202 <https://doi.org/10.1016/j.pocean.2019.102202> cc_by_4 CC-BY Publication - Article PeerReviewed 2019 ftnerc https://doi.org/10.1016/j.pocean.2019.102202 2023-02-04T19:49:39Z The spring bloom dominates the annual cycle of phytoplankton abundance in large regions of the world oceans. The mechanisms that trigger blooms have been studied for decades, but are still keenly debated, due in part to a lack of data on phytoplankton stocks in winter and early spring. Now however autonomous underwater gliders can provide high-resolution sampling of the upper ocean over inter-seasonal timescales and advance our understanding of spring blooms. In this study, we analyze bio-optical and physical observations collected by gliders at the Porcupine Abyssal Plain observatory site to investigate the impact of atmospheric forcing and light conditions on phytoplankton blooms in the temperate North Atlantic. We contrast three hypotheses for the mechanism of bloom initiation: the critical depth, critical turbulence, and dilution-recoupling hypotheses. Bloom initiation at our study site corresponded to an improvement in growth conditions for phytoplankton (increasing light, decreasing mixing layer depth) and was most consistent with the critical depth hypothesis, with the proviso that mixing depth (rather than mixed layer depth) was considered. After initiation, the observed bloom developed slowly: over several months both depth-integrated inventories and surface concentrations of chlorophyll a increased only by a factor of ~2 and ~3 respectively. We find that periods of convective mixing and high winds in winter and spring can substantially decrease (up to an order of magnitude) light-dependent mean specific growth rate for phytoplankton and prevent the development of rapid, high-magnitude blooms. Article in Journal/Newspaper North Atlantic Natural Environment Research Council: NERC Open Research Archive Progress in Oceanography 178 102202 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
The spring bloom dominates the annual cycle of phytoplankton abundance in large regions of the world oceans. The mechanisms that trigger blooms have been studied for decades, but are still keenly debated, due in part to a lack of data on phytoplankton stocks in winter and early spring. Now however autonomous underwater gliders can provide high-resolution sampling of the upper ocean over inter-seasonal timescales and advance our understanding of spring blooms. In this study, we analyze bio-optical and physical observations collected by gliders at the Porcupine Abyssal Plain observatory site to investigate the impact of atmospheric forcing and light conditions on phytoplankton blooms in the temperate North Atlantic. We contrast three hypotheses for the mechanism of bloom initiation: the critical depth, critical turbulence, and dilution-recoupling hypotheses. Bloom initiation at our study site corresponded to an improvement in growth conditions for phytoplankton (increasing light, decreasing mixing layer depth) and was most consistent with the critical depth hypothesis, with the proviso that mixing depth (rather than mixed layer depth) was considered. After initiation, the observed bloom developed slowly: over several months both depth-integrated inventories and surface concentrations of chlorophyll a increased only by a factor of ~2 and ~3 respectively. We find that periods of convective mixing and high winds in winter and spring can substantially decrease (up to an order of magnitude) light-dependent mean specific growth rate for phytoplankton and prevent the development of rapid, high-magnitude blooms. |
format |
Article in Journal/Newspaper |
author |
Rumyantseva, Anna Henson, Stephanie Martin, Adrian Thompson, Andrew F. Damerell, Gillian M. Kaiser, Jan Heywood, Karen J. |
spellingShingle |
Rumyantseva, Anna Henson, Stephanie Martin, Adrian Thompson, Andrew F. Damerell, Gillian M. Kaiser, Jan Heywood, Karen J. Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean |
author_facet |
Rumyantseva, Anna Henson, Stephanie Martin, Adrian Thompson, Andrew F. Damerell, Gillian M. Kaiser, Jan Heywood, Karen J. |
author_sort |
Rumyantseva, Anna |
title |
Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean |
title_short |
Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean |
title_full |
Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean |
title_fullStr |
Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean |
title_full_unstemmed |
Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean |
title_sort |
phytoplankton spring bloom initiation: the impact of atmospheric forcing and light in the temperate north atlantic ocean |
publishDate |
2019 |
url |
http://nora.nerc.ac.uk/id/eprint/525895/ https://nora.nerc.ac.uk/id/eprint/525895/1/untitled.pdf https://doi.org/10.1016/j.pocean.2019.102202 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
https://nora.nerc.ac.uk/id/eprint/525895/1/untitled.pdf Rumyantseva, Anna; Henson, Stephanie orcid:0000-0002-3875-6802 Martin, Adrian orcid:0000-0002-1202-8612 Thompson, Andrew F.; Damerell, Gillian M.; Kaiser, Jan; Heywood, Karen J. 2019 Phytoplankton spring bloom initiation: The impact of atmospheric forcing and light in the temperate North Atlantic Ocean. Progress in Oceanography, 178. 102202. https://doi.org/10.1016/j.pocean.2019.102202 <https://doi.org/10.1016/j.pocean.2019.102202> |
op_rights |
cc_by_4 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1016/j.pocean.2019.102202 |
container_title |
Progress in Oceanography |
container_volume |
178 |
container_start_page |
102202 |
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1766128385554120704 |