Project Overview: This PhD project investigates the role of organic carbon transport from land to sea during key climate events in Earth's history, with a focus on how these processes influence atmospheric CO₂ and future climate projections. By integrating organic geochemistry, Earth system modelling, and advanced statistical techniques, the research aims to quantify land-to-ocean carbon fluxes and organic carbon burial in marine shelves across a range of geological periods, from the Last Glacial Maximum to Cretaceous greenhouse states. Research Context: Human activities over the past 150 years have significantly increased atmospheric CO₂, warming the planet by approximately 1.5°C. The future trajectory of global warming depends on carbon cycle feedbacks—mechanisms that can either amplify or mitigate climate change. One such feedback is the export and burial of terrestrial organic carbon in marine environments, which may act as a negative feedback by sequestering CO₂. However, the strength and variability of this feedback through Earth's history remain poorly understood. Project Aims: The successful candidate will generate new organic geochemical measurements (including biomarkers and compound-specific isotopes) from ancient marine sediments and integrate these data with intermediate-complexity Earth-system models. The project will test the hypothesis that marine burial of terrestrial organic carbon is a negative climate feedback that intensifies during warm and wet climates. The results will provide critical insights for next-generation climate projections. Training and Environment: The PhD researcher will join Dr. Inglis's research group at the University of Southampton, working within a multidisciplinary team of PhD students, postdoctoral researchers, and technical specialists. The IGNITE programme offers comprehensive personal and professional development, including training in organic compound extraction, gas chromatography-isotope ratio-mass spectrometry, liquid chromatography-mass spectrometry, and programming (R, Python, Bash). Students will also gain experience in scientific communication through international conferences and meetings. Funding: The IGNITE Doctoral Landscape Award provides 3.5 years of funding (full- or part-time), including a tax-free stipend at the UKRI standard rate (£20,780 for 2025/26), full Home tuition fees, a waiver for the difference in international fees, and a Research Training Support Grant of £2,200 per year. Both UK and international students are eligible, though international studentships are limited to 30% of the cohort. Eligibility: Applicants should have a UK bachelor’s degree with upper second-class honours or higher in a relevant subject, or an international equivalent. English language proficiency is required (IELTS 6.5 overall, minimum 6.0 in all components, or equivalent). Experience in geochemistry, environmental science, or related fields is desirable, as are programming and laboratory skills. Application Process: Applications must be submitted online by 11:59pm on 8 January 2026. Prospective students are encouraged to contact the lead supervisor to discuss the project and their suitability before applying. Applicants may apply for up to two projects but are advised to tailor their application to one. The IGNITE programme supports diversity and offers a guaranteed interview scheme for qualifying UK applicants from racially minoritised backgrounds. References and Further Reading: See the project page for key references and further information about the research context and application process.