The surface–atmosphere exchanges of momentum, energy, water and trace gases (e.g. CO2) are central components of the Earth system. Their quantification, the understanding of their variability and their modeling can unlock key scientific questions like the impact of ecosystems on climate change and air pollution, and their capacity to cope with the ongoing climatic and atmospheric composition modifications. Meeting these challenges increasingly relies on observations at the ecosystem plot level obtained at experimental sites equipped with flux towers, which are organized in continental networks (ICOS for Europe), and the global FLUXNET database. In recent times, additional data are obtained through remote sensing, such as lidar, as well as drone measurements. Nevertheless, the overall three-dimensional characterization of the total fluxes remains challenging, as the measurements remain sparse in space and time. In recent years, data-assimilation algorithms have emerged that allow to combine sparse flow measurements in the atmospheric boundary layer with large-eddy simulations to reconstruct in the three-dimensional turbulent flow field (e.g. Bauweraerts & Meyers, J. Fluid Mech 906, 2012). Applying such algorithms for reconstruction of surface–atmosphere fluxes promises significant new insights in the underlying physical phenomena, and will allow to better characterize their impact on climate and environment.

Research: The research focuses on the development of data-assimilation methods that fuse together large-eddy simulations and experimental data for turbulent flux reconstruction of energy and trace gases in the atmospheric boundary layer. To this end, the KU Leuven LES code SP-Wind is used. This is a simulation code that is routinely run on the high-performance infrastructure of the Flemish Supercomputer Center, and is efficiently parallelized up to 10000 cores. Data from extensive experimental campaigns are provided by other researchers in the project.

Timeline and remuneration: Immediate start is possible. The PhD position lasts for the duration of four years, and is carried out at the University of Leuven. The candidate also takes up a limited amount (approx. 10% of the time) of teaching activities. The remuneration is generous and is in line with the standard KU Leuven rates. It consists of a net monthly salary of about 2400 Euro (in case of dependent children or spouse, the amount can be somewhat higher). Following Belgian law, the salary is automatically adjusted for inflation based on the smoothed health index.

Candidates have a master degree in one of the following or related fields: fluid mechanics, aerospace or mathematical engineering, numerical mathematics, or computational physics. They should have a good background or interest in fluid mechanics, optimization, simulation, and programming (Fortran, C/C++, MATLAB, Python, …). Proficiency in English is a requirement. The position adheres to the European policy of balanced ethnicity, age and gender. Persons of all origins and gender are encouraged to apply.

To apply, use the KU Leuven online application platform. (applications by email are not considered) Please include:
a) an academic CV and a PDF of your diplomas and transcript of course work and grades
b) a statement of research interests and career goals, indicating why you are interested in this position
c) a sample of technical writing, e.g. a paper with you as main author, or your bachelor or master thesis
d) at least one recommendation letter
d) a list of at least two additional references (different from recommendation letters): names, phone numbers, and email addresses
e) some proof of proficiency in English (e.g. language test results from TOEFL, IELTS, CAE, or CPE)

Please send your application as soon as possible, and before April 4th, 2024.
Decision: when a suitable candidate applies.
Starting date: immediate start possible, preferably before May 1st 2024. Later start can be negotiated.