Publication Date:
2024-04-04
Description:
Seamounts, such as the Ewing Seamount in the south-east Atlantic, offer a habi-
tat for Vulnerable Marine Ecosystems (VMEs) with increased biological activity
compared to the surrounding deep sea. This is due to characteristic circulation
features, such as a ’Taylor cap’ with a horizontal anticyclonic cell and vertical cir-
culation cells that transport nutrient-rich water from the depths to the slopes and
summit of the seamount. With the help of ocean model data and Lagrangian simu-
lations, favourable conditions for marine species can be observed and quantified.
One method for this is the description of the ’retention potential’, the likelihood of
particles, for example nutrients or larvae, to remain in a certain area. Experiments
with Parcels were carried out to investigate how the different model formulations
and resolutions of INALT20 and ROMS-AGRIF affect the particle spreading at the
Ewing Seamount. These model configurations differ both in the horizontal and ver-
tical resolution, the formulation of the vertical axis and the atmospheric and tidal
forcing. With coarser resolution and a vertical axis with levels of constant depth,
there is no anticyclonic cell around the summit. Additionally, velocities near the
bathymetry are generally low compared to when using terrain-following coordi-
nates. As a result, particles are carried away from the seamount at a slower rate,
which increases the retention potential. Tides, in turn, reduce this potential, and
an atmospheric forcing with interannual variability contributes to greater variabil-
ity in the particle distribution.
Keywords:
Course of study: MSc Climate Physics
Type:
Thesis
,
NonPeerReviewed
Format:
text
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