Postdoctoral Position on Ocean Flow Around Offshore Wind Turbine M - F H/F - 29

Join Ifremer, an ally of planetary well-being, to gain a better understanding of and better protection for the ocean.

From the abyss to the surface, from the coast to the open SEA, Ifremer is the French research institute that is wholly dedicated to the Ocean. Its teams carry out research, innovate and produce expert reports to protect the ocean, exploit its resources in a responsible manner and shares marine data.

Ifremer contributes its scientific expertise to throw light on public policies and develops solutions drawn from the ocean to meet the challenges of the ecological transition. Ifremer is the operator of France's oceanographic fleet with its shipbuilding subsidiary Genavir, and imagines, designs and deploys leading edge technological means to solve the ocean's mysteries.

Join our teams, made up of 1500 scientists and research support staff, present all along the coastal areas of France and French overseas territories.

www.ifremer.frDeadline for applications: 01/10/2025

- Presentation of the department, research unit or laboratory

The Laboratory of Physical and Spatial Oceanography (LOPS, www.umr-lops.fr) is a joint research unit affiliated to Ifremer, and to other three French research and higher education institutions : the French National Centre for Scientific Research (CNRS, www.cnrs.fr), the French National Research Institute for Sustainable Development (IRD, www.ird.fr) and the University of Bretagne Occidentale (UBO, www.univ-brest.fr). The LOPS is one of the seven labs that make up Institut Universitaire Européen de la Mer (IUEM, www-iuem.univ-brest.fr), and one of the three labs of the Océanographie et Dynamique des Ecosystèmes department at Ifremer. Research at LOPS is organized into 4 teams, working on the coastal ocean, the oceans and climate, satellite remote sensing and air-sea interface dynamics and ocean spatio-temporal scale interactions. The lab maintains and develops a unique know-how in oceanographic measurements at SEA, and the interpretation of satellite remote sensing data.

The position will be hosted in LOPS' « Coastal Ocean » team which is dedicated the understanding of the dynamics of the coastal ocean. This team work on 4 areas of scientific research : fine-scale dynamics and the coastal environment ; extreme (or rare) events and climate change ; dynamics of boundary layers ; involvement in research support infrastructures.

- Introduction of the position to be filled and its position in the organization chart

As plans for massive deployments of Offshore Wind Farms (OWF) are made at the international levels, the question of the effects of OWF on the physical environments represent an outstanding scientific question for the oceanographic community [Rezaei et al. 2023]. Out of the multiple expected effects, the mixing induced by turbulent wakes in the lee of wind turbines stands out and has attracted the attention of the scientific community for several years now [Carpenter et al. 2016, Floetter et al. 2017, Dorrel et al. 2022]. Much remains to be understood regarding how intense this mixing is, how sensitive it is to environmental parameters (e.g. currents, the oceanic stratification, waves and winds), and, how it integrates temporally and spatially to produce an effect on the larger scales (park and region). This knowledge is a prerequisite that is lacking at the moment for the design of parametrization of wake induced mixing in numerical model of the ocean circulation aiming at quantifying the larger scale and long-term effects of OWF on the marine environment.

The postdoctoral position will be hosted in the LOPS laboratory and will be supported by the EMOI project. EMOI is a 3 years long project (2025-2027) lead by the French national institute for marine sciences (Ifremer) whose aim is to improve the state of the art of our scientific knowledge of OWF effects on the marine environment (biology, ecology, chemistry, physics). The postdoctoral researcher will directly contribute to the work package dedicated to the understanding of OWF effects on the physical environment with focus on wake induced mixing.

- General areas of responsibility

This postdoctoral position aims at improving our understanding of the effects of Offshore Wind Farms on the physical environment. This scientific question is outstanding given the massive deployments planned worldwide. The focus is on the mixing associated with hydrological wakes in the lee of wind turbines. We propose to combine in situ experiments, high resolution numerical simulations and satellite observations in order to describe turbulent processes associated with wind turbine wakes and the induced mixing. Sensitivities to environmental conditions will be quantified (e.g. currents, hydrological stratification, waves). This job will be conducted as part of an ambitious multi-disciplinary project EMOI which aims at quantifying the effect of Offshore Wind Farms on the marine environment in general.

- Principal activities

The objectives of this postdoctoral position are in general to improve our understanding of wake induced mixing. Several approaches will be employed to do that:

In situ experiments - core approach

Several in situ experimental campaigns will be conducted within the framework of EMOI which will aim at characterizing hydrological wakes (mean and turbulent properties, mixing) in the lee of wind turbines. Such observations remain a challenge owing to the small scales associated with these wakes and their marginal temporal stability. Towed CTD chains, shipboard ADCP measurements and drifting surface and subsurface platforms will be deployed.

Two other approaches may be considered depending on the candidate background and progresses made on the analysis of the in situ data:

Numerical modeling

CFD numerical simulations of wake flows will be performed. The analysis of simulation outputs will first be compared to in situ experimental observations in order to validate the ability of these simulations to accurately represent hydrological wakes. Pending satisfactory results, further simulations will be performed in order to explore the parameter space defined by the relevant environmental conditions (e.g. currents, hydrological stratification).

Satellite Observations

The third objective is more exploratory and deals with satellite observations of wakes. Reports on such observations have been made with optical imagery [Vanhellemont et al. 2014], radars [Li et al. 2014]. The goal is here to investigate what quantitative information may be extracted from satellite observations of hydrological wakes in the lee of wind turbines.

- Collaborative work environment

Internal collaborative relationship

- The postdoctoral researcher will interact with researchers, engineers and technicians from LOPS as well as from Ifremer's laboratory of marine hydrodynamics (Boulogne/Mer) and the LERN laboratory (Port en Bessin).
- External collaborative relationship
- N/A