The University of Bremen at MARUM - Center for Marine Environmental Sciences within the Cluster of Excellence «The Ocean Floor - Earth's Uncharted Interface» is seeking to fill - subject to the approval of funds - starting on January 1, 2026 at the earliest, up to 15 positions as Research Associates (Doctoral Candidates) (f/m/d) German Salary Scale 13 TV-L/TVöD (depending on the project partner) at 75% of the regular weekly working hours (29.4 working hours / week) for a fixed-term period of 4 years, until at most December 31, 2029 (according to § 2 WissZeitVG) with the aim of obtaining a doctorate. International applications are expressly encouraged. We aim to increase the proportion of women and strongly encourage female applicants to apply. The Cluster of Excellence is a joint project of the Universities of Bremen and Oldenburg and a consortium of five partner institutions: Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Max Planck Institute for Marine Microbiology, Leibniz Centre for Tropical Marine Research, Constructor University and the Hanse-Wissenschaftskolleg - Institute for Advanced Study. Funded by the German Excellence Strategy, the cluster quantifies exchange processes at the ocean floor and investigates their role in the Earth system. The cluster's research portfolio consists of projects that (i) decipher the processes that control the transport of biogenic particles to the ocean floor under changing climate conditions, (ii) balance the transfer of carbon and other elements between the ocean floor and seawater, (iii) investigate how ecosystems on the ocean floor react to environmental changes and (iv) develop scenarios for a «warmer world» from climate archives on the ocean floor with the help of climate models. Further information about the Cluster of Excellence can be found at https://theoceanfloor.de. Along these central research topics, the Cluster offers a structured training for doctoral students in an interdisciplinary framework of marine biogeochemistry, marine geosciences, marine (micro)biology and (paleo)climatology. The cluster offers a versatile qualification program in which doctoral researchers can strengthen their professional competence and develop their personal skills. The program offers rich opportunities for interdisciplinary exchange and collaboration across different disciplines of marine sciences, including research stays at partner institutions. Further details on the training program can be found at https://theoceanfloor.de/en/The-Ocean-Floor/ECR-support.html. In this context, the partner institutions of the cluster invite applications for: Doctoral researcher positions in the areas: EXC1-01 Carbon Sequestration at the Molecular Level https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-01.html EXC1-02 The role of iron cycling in sequestration and remobilization of organic matter https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-02.html EXC1-03 Molecular Gatekeepers of Carbon Sequestration https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-03.html EXC1-04 The role of lateral transport in enhancing carbon fluxes to the ocean floor https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-04.html EXC1-05 Unraveling the spatio-temporal development of cold-water coral ecosystems https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-05.html EXC1-06 Anthropogenic particulate carbon from source to sink https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-06.html EXC1-07 Lighting the Way: Metabolic Tracing of Plankton Sugars in Marine Sediments https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-07.html EXC1-08 From surface to seafloor: process-oriented modelling of particulate organic carbon https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-08.html EXC1-09 Metal-microbe interactions in hydrothermal plumes https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-09.html EXC1-10 Deconstructing Arctic hydrothermal systems https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-10.html EXC1-11 Nanoscale Interactions of Vent-Derived Particles https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-11.html EXC1-12 Deep-sea natural petroleum seeps and hydrothermal systems https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-12.html EXC1-13 Forecasting changes in pelagic ecosystem functions in a warmer ocean https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-13.html EXC1-14 Determining the pre-anthropogenic baseline of pelagic biodiversity change https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-14.html EXC1-15 Decoding feedbacks and thresholds https://theoceanfloor.de/en/The-Ocean-Floor/Career/Jobs/EXC-DR-1-15.html Follow the links for detailed project descriptions and application requirements. It is recommended to contact the cluster spokesperson Prof. Heiko Pälike ( speaker-exc-oceanfloor@uni-bremen.de ) or the responsible researchers of the individual projects for further information. Place of employment and remuneration (TV-L or TVöD) depend on the partner institutions where the project is located. Further information can be found in the project descriptions. We offer you: A secure salary and statutory health and social insurance. In the Cluster of Excellence, doctoral researchers are mentored by a team of experienced scientists and benefit from a large international network of doctoral researchers. We offer flexible working hours and the opportunity to work remotely. In addition, 30 days of vacation are standard with us. Our health management offers you, e.g., discounted company fitness programs, as well as internal health-promoting offers (e.g. health courses). Easy access to your workplace by public transport or bicycle. All partner institutions in the cluster pursue a strategy of diversity. We therefore welcome all applications regardless of gender, nationality, ethnic and social origin, religion/belief, disability, age, sexual orientation and identity. Disabled persons with essentially equal professional and personal qualifications will be given priority when applying. You can apply for up to three projects, stating a prioritization. The application must include a letter of motivation, your CV with certificates, a list of publications (if applicable) and the contact details of two references. Please send your application with your complete and informative documents, quoting the reference number A179-25, by 25.07.2025 as a PDF file (max. 5 MB) by unencrypted electronic mail to: office-exc-oceanfloor@uni-bremen.de or by mail to: MARUM - Center for Marine Environmental Sciences, University of Bremen University of Bremen Prof. Dr. Heiko Pälike Leobener Street 8 28359 Bremen Bremen, Germany Please note that no photos are to be attached to the application documents. We ask you to submit only copies (no portfolios), as we cannot return them. Once the selection process has been completed, your application documents will be stored in accordance with the legal requirements and then destroyed. Any costs for the application procedure cannot be reimbursed.