Lagrangian coherent structures deduced from HF radar measurements

Author(s):  
Francesco Enrile ◽  
Giovanni Besio ◽  
Marcello G. Magaldi ◽  
Carlo Mantovani ◽  
Simone Cosoli ◽  
...  
Author(s):  
Anusmriti Ghosh ◽  
Kabir Suara ◽  
Scott W. McCue ◽  
Yingying Yu ◽  
Tarmo Soomere ◽  
...  

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alberto Baudena ◽  
Enrico Ser-Giacomi ◽  
Donatella D’Onofrio ◽  
Xavier Capet ◽  
Cedric Cotté ◽  
...  

AbstractOceanic frontal zones have been shown to deeply influence the distribution of primary producers and, at the other extreme of the trophic web, top predators. However, the relationship between these structures and intermediate trophic levels is much more obscure. In this paper we address this knowledge gap by comparing acoustic measurements of mesopelagic fish concentrations to satellite-derived fine-scale Lagrangian Coherent Structures in the Indian sector of the Southern Ocean. First, we demonstrate that higher fish concentrations occur more frequently in correspondence with strong Lagrangian Coherent Structures. Secondly, we illustrate that, while increased fish densities are more likely to be observed over these structures, the presence of a fine-scale feature does not imply a concomitant fish accumulation, as other factors affect fish distribution. Thirdly, we show that, when only chlorophyll-rich waters are considered, front intensity modulates significantly more the local fish concentration. Finally, we discuss a model representing fish movement along Lagrangian features, specifically built for mid-trophic levels. Its results, obtained with realistic parameters, are qualitatively consistent with the observations and the spatio-temporal scales analysed. Overall, these findings may help to integrate intermediate trophic levels in trophic models, which can ultimately support management and conservation policies.


1986 ◽  
Vol 11 (2) ◽  
pp. 219-234 ◽  
Author(s):  
L. Wyatt ◽  
J. Venn ◽  
G. Burrows ◽  
A. Ponsford ◽  
M. Moorhead ◽  
...  

Author(s):  
S. Datta‐Barua ◽  
N. Pedatella ◽  
K. R. Greer ◽  
N. Wang ◽  
L. Nutter ◽  
...  

2014 ◽  
Vol 21 (3) ◽  
pp. 659-675 ◽  
Author(s):  
J. Marmain ◽  
A. Molcard ◽  
P. Forget ◽  
A. Barth ◽  
Y. Ourmières

Abstract. HF radar measurements are used to optimize surface wind forcing and baroclinic open boundary condition forcing in order to constrain model coastal surface currents. This method is applied to a northwestern Mediterranean (NWM) regional primitive equation model configuration. A new radar data set, provided by two radars deployed in the Toulon area (France), is used. To our knowledge, this is the first time that radar measurements of the NWM Sea are assimilated into a circulation model. Special attention has been paid to the improvement of the model coastal current in terms of speed and position. The data assimilation method uses an ensemble Kalman smoother to optimize forcing in order to improve the model trajectory. Twin experiments are initially performed to evaluate the method skills. Real measurements are then fed into the circulation model and significant improvements to the modeled surface currents, when compared to observations, are obtained.


2015 ◽  
Vol 65 (5) ◽  
pp. 679-690 ◽  
Author(s):  
Johannes Röhrs ◽  
Ann Kristin Sperrevik ◽  
Kai Håkon Christensen ◽  
Göran Broström ◽  
Øyvind Breivik

Sign in / Sign up

Export Citation Format

Share Document