|
|
|
|
|
| Chenillat, Fanny; Riviere, Pascal; Capet, Xavier; Di Lorenzo, E.; Blanke, Bruno. |
| On interannual and longer time scales, dynamical and biogeochemical fluctuations in the North Pacific are dominated by two modes of variability, namely the Pacific Decadal Oscillation and the North Pacific Gyre Oscillation (NPGO). In this study the regional expression of the NPGO in the California Current System (CCS) is detailed. The statistical relationship between the NPGO index and nearshore wind variability (mostly upwelling favorable) along the U. S. West coast is strongest in the wintertime (December to March) off Central California. Most importantly, NPGO fluctuations are associated with a seasonal shift of 1-2 months in the onset of the upwelling season. Regional numerical simulations show that an early (late) onset of upwelling during the... |
| Tipo: Text |
|
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00063/17396/15062.pdf |
| |
|
|
| Franks, Peter J. S.; Di Lorenzo, Emanuele; Goebel, Nicole L.; Chenillat, Fanny; Riviere, Pascal; Edward, Christopher A.; Miller, Arthur J.. |
| Understanding the effects of climate change on planktonic ecosystems requires the synthesis of large, diverse data sets of variables that often interact in nonlinear ways. One fruitful approach to this synthesis is the use of numerical models. Here, we describe how models have been used to gain understanding of the physical-biological couplings leading to decadal changes in the southern California Current ecosystem. Moving from basin scales to local scales, we show how atmospheric, physical oceanographic, and biological dynamics interact to create long-term fluctuations in the dynamics of the California Current ecosystem. |
| Tipo: Text |
|
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00156/26735/24829.pdf |
| |
|
|
| Chenillat, Fanny; Blanke, Bruno; Grima, Nicolas; Franks, Peter J. S.; Capet, Xavier; Rivière, Pascal. |
| Eulerian models coupling physics and biology provide a powerful tool for the study of marine systems, complementing and synthesizing in situ observations and in vitro experiments. With the monotonic improvements in computing resources, models can now resolve increasingly complex biophysical interactions. Quantifying complex mechanisms of interaction produces massive amounts of numerical data that often require specialized tools for analysis. Here we present an Eulerian-Lagrangian approach to analyzing tracer dynamics in moving fluids. As an example of its utility, we apply this tool to quantifying plankton dynamics in oceanic mesoscale coherent structures. In contrast to Eulerian frameworks, Lagrangian approaches are particularly useful for revealing... |
| Tipo: Text |
Palavras-chave: Biophysicalinteractions; Planktondynamics; Ecosystemfunctioning; Lagrangiantrajectories; Ocean dynamics; Mesoscaleprocesses; Eddytracking; Coherentstructures. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00469/58028/60447.pdf |
| |
|
|
| Chenillat, Fanny; Riviere, Pascal; Capet, Xavier; Franks, Peter J. S.; Blanke, Bruno. |
| The variability of the California Current System (CCS) is primarily driven by variability in regional wind forcing. In particular, the timing of the spring transition, i.e., the onset of upwelling-favorable winds, varies considerably in the CCS with changes in the North Pacific Gyre Oscillation. Using a coupled physical-biogeochemical model, this study examines the sensitivity of the ecosystem functioning in the CCS to a lead or lag in the spring transition. An early spring transition results in an increased vertical nutrient flux at the coast, with the largest ecosystem consequences, both in relative amplitude and persistence, hundreds of kilometers offshore and at the highest trophic level of the modeled food web. A budget analysis reveals that the... |
| Tipo: Text |
|
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00146/25706/24010.pdf |
| |
|
|
|
