Janet Rethemeyer

The University of Cologne, one of Europe's largest and oldest universities, is offering a doctoral position in biochemistry/isotope geochemistry with a focus on radiocarbon. The position is based in the Institute of Geology and Mineralogy, specifically within the Organic Geochemistry & Radiocarbon group. The research project centers on characterizing microbial communities and their role in carbon cycling in permafrost soils of the Arctic, particularly as the region becomes warmer and wetter. Key research activities include measuring microbial activity, utilizing carbon isotopes (¹³C, ¹⁴C) to quantify carbon uptake, respiration, and CO2 emission sources, and assessing the impact of plant-derived carbon inputs and mineral-associated carbon stabilization on microbial processes. The successful candidate will plan and conduct field measurements in Arctic regions, organize fieldwork logistics, sample sediments and water, and measure CO2 and CH4 fluxes. Laboratory work will involve analyzing organic matter composition and microbial communities using organic-geochemical techniques, conducting experiments, and applying or improving methods such as CO2 and CH4 samplers and vacuum systems. Data analysis will be performed using statistical methods, and results will be published in peer-reviewed journals and presented at conferences. Applicants must have an M.Sc. in geosciences, environmental sciences, chemistry, or related fields. Essential qualifications include a strong background in biogeochemical cycles, isotope geochemical and/or organic geochemical methods, creativity in digital data analysis, ability to work independently and collaboratively, technical and analytical skills, and proficiency in English. The position requires participation in several 2-3 week field campaigns in the Arctic. The University of Cologne offers a diverse working environment with equal opportunities, support for work-life balance, advanced training, occupational health management, flexible working models, and remote work options. The position is part-time (27.88 hours/week), available from 1 May 2026, and limited until 30 April 2029. Salary is based on remuneration group 13 TV-L of the German public sector, contingent on fund allocation. Women and candidates from diverse backgrounds are encouraged to apply. Applications should be submitted online via the University of Cologne job portal, including a letter of motivation, CV, list of publications, and copies of certificates (no photo), referencing Wiss2601-10. The deadline is 23 March 2026. For further inquiries, contact Professor Dr. Janet Rethemeyer at [email protected].