The Max Planck Institute for Biogeochemistry (MPI-BGC) in Jena is dedicated to interdisciplinary fundamental research in the field of Earth system sciences with a focus on climate and ecosystems. The internationally renowned institute, which currently employs around 250 people, celebrated its 25th anniversary in 2022. Jena is known for high-tech industry, internationally renowned research institutions and a modern university, but it also has a beautiful natural setting in the green Saale valley with steep limestone slopes. The city of Jena has an active student scene and a diverse cultural life. We are looking to fill a PhD position (m/f/d) - Improving understanding of seasonal and interannual carbon and water fluxes using process-based modelling for 3 years, starting in September 2025 at the earliest.

Background and position description

The Amazon Tall Tower Observatory (ATTO) project is a German-Brazilian research collaboration dedicated to improving our understanding of processes in intact Amazonian forests and their interactions with the atmosphere in the changing Earth system. Building on insights gained from previous and ongoing observational studies at ATTO, this project will use vegetation modeling as a powerful tool to investigate the impacts of current climate extremes and future projections on the Amazon rainforests. The focus of this project is on advancing the representation of key processes such as leaf phenology and plant hydraulics of tropical ecosystems that remain incompletely represented in the current generation of models, but are fundamental to understanding seasonal and interannual variations, as well as the impacts of extremes.

Specifically, the successful PhD candidate will use the terrestrial biosphere model QUINCY to improve our understanding of tropical process representation. Extensive experimental data from previous ATTO phases, including phenocam and eddy-covariance observations, but also functional traits of species will be used. Subsequently, the improved QUINCY model will be used to scale insights gained at the ATTO site to the Amazon basin, enabling a comprehensive investigation of extreme event impacts on the rainforest.

This project is part of the BMBF-funded ATTO-Synthesis project, an international and highly collaborative project. The PhD student will closely collaborate with experimentalists from the ATTO project, the terrestrial biosphere modelling group at MPI BGC, and other international Institutes and Universities. There will also be the possibility of regularly participating in the ATTO workshop and project meetings in Manaus, Brazil. For questions about the project, please do not hesitate to contact Phillip Papastefanou or Sönke Zaehle.

Your tasks

• Applying and analysing the QUINCY model at the ATTO site and on the Amazon basin level
• Integrating different observational data sources into model calibration and testing
• Based on comparison to data, contribute to the further development of relevant processes regarding phenology and plant hydraulics
• Interacting with experimental groups of the ATTO project to discuss data-model integration

Your profile

• Diploma or Master´s degree in geosciences, environmental sciences, physics, or related disciplines
• Knowledge about ecosystem processes, climate change and biogeochemical cycles, as well as the representation of such processes in vegetation models is an asset
• Experience with (scientific) programming (Python, R or other languages)
• Comfortable with mathematics and analytical systems thinking
• Curiosity and willingness to expand their knowledge in related disciplines
• Very good written and spoken English

Our offer

The full-time position as a PhD researcher (m/f/d) is to be filled with a start in September 2025 or later. Part-time work is generally possible. The position will be evaluated and graded following the collective agreement according to TVöD Bund. The Max Planck Society (MPS) strives for gender equality and diversity. The MPS aims to increase the proportion of women in areas where they are underrepresented. Women are therefore explicitly encouraged to apply. We welcome applications from all fields. The Max Planck Society has set itself the goal of employing more severely disabled people. Applications from severely disabled persons are expressly encouraged.

Your application

Are you interested? Please send us your application with cover letter, curriculum vitae as well as names and contact information of two references summarised in a PDF file (max. 10 MB) by June 15, 2025, quoting the reference number 10/2025 by e-mail to bewerbung@bgc-jena.mpg.de or to the

Max-Planck-Institut für Biogeochemie
Personalbüro: Kennwort „PhD position 1”
Hans-Knöll-Straße 10
07745 Jena
Germany

We ask that you do not use application folders, but only submit copies, as your documents will be destroyed in accordance with data protection regulations after the application process has been completed. We look forward to receiving your application!