High-resolution temperature observations of a trapped nonlinear diurnal tide influencing cold-water corals on the Logachev mounds
A high-resolution thermistor string mooring of 120 m length was used to measure turbulence processes in the water layer above the foot of a densely populated cold-water coral mound at 919 m depth at the southeast slope of Rockall Bank in the Logachev area, North-East Atlantic Ocean. As expected from...
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Language: | English |
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ftnioz:oai:imis.nioz.nl:240819 2023-05-15T17:38:32+02:00 High-resolution temperature observations of a trapped nonlinear diurnal tide influencing cold-water corals on the Logachev mounds van Haren, H. Mienis, F Duineveld, G.C.A. Lavaleye, M.S.S. 2014 http://imis.nioz.nl/imis.php?module=ref&refid=240819 en eng info:eu-repo/semantics/altIdentifier/wos/000338415200002 info:eu-repo/semantics/altIdentifier/doi/oi.org/10.1016/j.pocean.2014.04.021 http://imis.nioz.nl/imis.php?module=ref&refid=240819 info:eu-repo/semantics/closedAccess %3Ci%3EProg.+Oceanogr.+125%3C%2Fi%3E%3A+16-25.+%3Ca+href%3D%22http%3A%2F%2Fdx.doi.org%2F10.1016%2Fj.pocean.2014.04.021%22+target%3D%22_blank%22%3Ehttp%3A%2F%2Fdx.doi.org%2F10.1016%2Fj.pocean.2014.04.021%3C%2Fa%3E info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2014 ftnioz https://doi.org/10.1016/j.pocean.2014.04.021 2022-05-01T13:59:41Z A high-resolution thermistor string mooring of 120 m length was used to measure turbulence processes in the water layer above the foot of a densely populated cold-water coral mound at 919 m depth at the southeast slope of Rockall Bank in the Logachev area, North-East Atlantic Ocean. As expected from previous current observations, the temperature data reveal a dominant diurnal (tidal) periodicity associated with topography-trapped, weakly bottom-intensified waves. These baroclinic diurnal waves are driven to (near-) resonance around the mound and have vertical amplitudes exceeding the mooring line. Their horizontal excursion length matches the size of the mound, which causes a residual current around and flux up the mound. As their particle velocities also match the phase speed of the wave traveling around the mound, these waves can become highly nonlinear and show largest turbulence due to wave-breaking at the transition from warming downslope to cooling upslope tidal phase. Averaged over the entire 9-day time series and the 120 m vertical range, mean turbulent kinetic energy dissipation amounts to 2.2 ± 1.1 × 10-7 W kg-1 (and mean vertical eddy diffusivity to 9 ± 5 × 10-3 m2 s-1) with short-term variations over four orders of magnitude. Such large turbulence, more than 100 times larger than open-ocean values and comparable with that observed in tidally energetic shelf break-shallow sea areas, will affect the nutrient replenishment of the cold-water corals. Article in Journal/Newspaper North East Atlantic NIOZ Repository (Royal Netherlands Institute for Sea Research) Rockall Bank ENVELOPE(-16.519,-16.519,55.821,55.821) Progress in Oceanography 125 16 25 |
institution |
Open Polar |
collection |
NIOZ Repository (Royal Netherlands Institute for Sea Research) |
op_collection_id |
ftnioz |
language |
English |
description |
A high-resolution thermistor string mooring of 120 m length was used to measure turbulence processes in the water layer above the foot of a densely populated cold-water coral mound at 919 m depth at the southeast slope of Rockall Bank in the Logachev area, North-East Atlantic Ocean. As expected from previous current observations, the temperature data reveal a dominant diurnal (tidal) periodicity associated with topography-trapped, weakly bottom-intensified waves. These baroclinic diurnal waves are driven to (near-) resonance around the mound and have vertical amplitudes exceeding the mooring line. Their horizontal excursion length matches the size of the mound, which causes a residual current around and flux up the mound. As their particle velocities also match the phase speed of the wave traveling around the mound, these waves can become highly nonlinear and show largest turbulence due to wave-breaking at the transition from warming downslope to cooling upslope tidal phase. Averaged over the entire 9-day time series and the 120 m vertical range, mean turbulent kinetic energy dissipation amounts to 2.2 ± 1.1 × 10-7 W kg-1 (and mean vertical eddy diffusivity to 9 ± 5 × 10-3 m2 s-1) with short-term variations over four orders of magnitude. Such large turbulence, more than 100 times larger than open-ocean values and comparable with that observed in tidally energetic shelf break-shallow sea areas, will affect the nutrient replenishment of the cold-water corals. |
format |
Article in Journal/Newspaper |
author |
van Haren, H. Mienis, F Duineveld, G.C.A. Lavaleye, M.S.S. |
spellingShingle |
van Haren, H. Mienis, F Duineveld, G.C.A. Lavaleye, M.S.S. High-resolution temperature observations of a trapped nonlinear diurnal tide influencing cold-water corals on the Logachev mounds |
author_facet |
van Haren, H. Mienis, F Duineveld, G.C.A. Lavaleye, M.S.S. |
author_sort |
van Haren, H. |
title |
High-resolution temperature observations of a trapped nonlinear diurnal tide influencing cold-water corals on the Logachev mounds |
title_short |
High-resolution temperature observations of a trapped nonlinear diurnal tide influencing cold-water corals on the Logachev mounds |
title_full |
High-resolution temperature observations of a trapped nonlinear diurnal tide influencing cold-water corals on the Logachev mounds |
title_fullStr |
High-resolution temperature observations of a trapped nonlinear diurnal tide influencing cold-water corals on the Logachev mounds |
title_full_unstemmed |
High-resolution temperature observations of a trapped nonlinear diurnal tide influencing cold-water corals on the Logachev mounds |
title_sort |
high-resolution temperature observations of a trapped nonlinear diurnal tide influencing cold-water corals on the logachev mounds |
publishDate |
2014 |
url |
http://imis.nioz.nl/imis.php?module=ref&refid=240819 |
long_lat |
ENVELOPE(-16.519,-16.519,55.821,55.821) |
geographic |
Rockall Bank |
geographic_facet |
Rockall Bank |
genre |
North East Atlantic |
genre_facet |
North East Atlantic |
op_source |
%3Ci%3EProg.+Oceanogr.+125%3C%2Fi%3E%3A+16-25.+%3Ca+href%3D%22http%3A%2F%2Fdx.doi.org%2F10.1016%2Fj.pocean.2014.04.021%22+target%3D%22_blank%22%3Ehttp%3A%2F%2Fdx.doi.org%2F10.1016%2Fj.pocean.2014.04.021%3C%2Fa%3E |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/000338415200002 info:eu-repo/semantics/altIdentifier/doi/oi.org/10.1016/j.pocean.2014.04.021 http://imis.nioz.nl/imis.php?module=ref&refid=240819 |
op_rights |
info:eu-repo/semantics/closedAccess |
op_doi |
https://doi.org/10.1016/j.pocean.2014.04.021 |
container_title |
Progress in Oceanography |
container_volume |
125 |
container_start_page |
16 |
op_container_end_page |
25 |
_version_ |
1766139021143048192 |