General information
Offer title : Postdoctoral researcher in continental surface modeling (M/F) (H/F)
Reference : UAR636-ALERUB-019
Number of position : 1
Workplace : PARIS 05
Date of publication : 30 September 2025
Type of Contract : Researcher in FTC
Contract Period : 12 months
Expected date of employment : 1 December 2025
Proportion of work : Full Time
Remuneration : From 3081,33€
Desired level of education : Doctorate
Experience required : Indifferent
Section(s) CN : 01 – Interactions, particles, nuclei, from laboratory to cosmos
Missions
The postdoctoral researcher will conduct research on land surface modeling, in order to improve simulations of water, energy and carbon balances exchanged with the atmosphere, using the ORCHIDEE model (developed at the Institut Pierre Simon Laplace, IPSL). He or she will seek to improve the representation of sub-grid processes, focusing mainly on hydrology. The mission involves three axes. The first concerns the improvement of the stability of the numerical scheme dealing with vertical water movements in the soil (advection – diffusion) in specific cases of strong gradients. The second concerns the implementation of the effect of soil organic carbon on the hydraulic properties of soils (mainly porosity), paying particular attention to high latitudes, in order to develop an adequate representation of this effect in a land surface model. Finally, the last predominant axis concerns the implementation of a multiple energy and water balance in ORCHIDEE in order to be able to represent the sub-grid heterogeneity of these balances (the current model having only 1 energy balance and 3 water balances). The objective in partnership with other developers of the ORCHIDEE model is to implement a flexible scheme to have independent water/energy balances for each plant functional type represented in the model. In general, he or she will collaborate with various researchers at IPSL to integrate the developments made into the rest of the model and to parameterize them. He or she will contribute to the publication of the associated research results in scientific journals and will participate in international conferences to present his or her work and exchange with the scientific community on the progress made.
Activities
The main activities of the postdoctoral researcher for this position will include the following tasks:
• Implementing an energy balance multi-tiling in the ORCHIDEE model
• Investigating the effect of soil organic carbon on soil hydraulic properties and developing an adequate representation of this effect, with particular attention to high latitudes
• Improving the numerical scheme governing vertical water transfers in the soil to overcome numerical instabilities under certain conditions.
• Collaborate with other researchers to integrate and configure the various developments that will be made within the main ORCHIDEE model version.
• Analyze and interpret the results obtained with these new developments to draw relevant scientific conclusions.
• Write scientific articles for publication in specialized journals.
• Participate in international meetings and conferences to present progress and engage with the scientific community
Skills
• PhD in environmental sciences, applied mathematics, physics, or a related field.
• Strong expertise in numerical modeling.
• Proven experience working with a model of Earth’s surface functioning
Work Context
Position located at IPLS, Paris
