Missions

In the Arctic, local sources of air pollution (which tend to increase in a context of climate warming) can have an impact on human health and ecosystems. During particularly cold winters, populated areas in this region are subject to episodes of increased pollution, resulting from a combination of high local emissions, primarily from residential heating and electricity production, and meteorological conditions that trap pollution near the surface. Pollution plumes from power plant stacks are also present in higher atmospheric layers and may contribute to surface pollution when subsiding. The relative contribution of different sources to the surface content of gaseous or particulate pollutants remains highly uncertain. The regional chemistry-aerosol model WRF-Chem will be used to analyze the observations from the ALPACA (Alaskan Layered Pollution and Chemical Analysis) campaign, which took place in January-February 2022 in Fairbanks, Alaska. Time series data at the surface and vertical profiles, specifically regarding aerosols and trace gases (CO, O3, NO, and NO2), were collected during ALPACA. The WRF-Chem simulations will be compared to the available data to evaluate the emissions of trace gases developed specifically for the campaign, as well as the model's boundary layer dynamics. The simulations will help quantify the impact of different pollution sources on surface air quality and characterize their chemical signatures, taking into account the chemical aging of air masses. Particular focus will be placed on elevated sources such as power plant chimneys, whose plumes were detected during ALPACA. This work is part of the ANR CASPA project (Climate-relevant Aerosol Sources & Processes in the Arctic) (2021-2026), which is coordinated by LATMOS and represents the French contribution to ALPACA

Activities

The candidate will carry out data analysis and numerical modeling using the WRF-Chem model. This includes running the model, as well as handling and visualizing the results. This work also involves evaluating the model against the available data and conducting a more in-depth examination of the ALPACA data.

Skills

The candidate must hold a Master (or equivalent) in a relevant field such as atmospheric sciences, air pollution, or meteorology. Experience in computer programming (Fortran, Unix, Python, shell scripting) and data analysis is desirable. They should preferably be fluent in English and have strong written English skills. The candidate must be motivated, possess excellent organizational and communication skills, and be able to work effectively in a team.

Work Context

The candidate will be based at LATMOS (Laboratory for Atmospheres, Observations, and Space Science), on the Jussieu campus of Sorbonne University, in the heart of Paris, near landmarks such as Notre-Dame Cathedral and the Jardin des Plantes (http://www.latmos.ipsl.fr/index.php/en/le-laboratoire). They will join a team working on Arctic atmospheric composition and climate, using both field campaigns and modeling. LATMOS is a CNRS laboratory and part of the Pierre Simon Laplace Institute (IPSL) (http://www.ipsl.fr/).
The postdoc will work closely with Brice Barret, a CASPA project partner, at LAERO (https://www.aero.obs-mip.fr/) in Toulouse (southwest France), as well as with other CASPA and ALPACA collaborators

Constraints and risks

none

Additional Information

This is a fixed-term position for 4 months. The position will remain open until filled. The start date is flexible, but ideally in January 2025.
Work at LATMOS in central Paris: the site is accessible by public transportation with partial reimbursement of transport costs, and access to a university cafeteria. The candidate will have 44 days of vacation per year and will receive health coverage.