The Earth Surface Science group at Queen Mary University of London (QMUL) are seeking a 24-month PDRA to work on a Human Frontier Science Project (HFSP) funded project ‘The atmosphere: a living, breathing ecosystem?’. The project is a collaboration between QMUL’s School of Geography, the University of Guelph (Canada), Monash University (Australia) and Arizona State University (USA). The team aim to resolve the composition, capabilities, and activities of atmospheric microbes at a global scale, with the overall goal to distinguish whether the atmosphere exhibits structure and microbial activity characteristic of a true ecosystem, or if it is simply a passive dispersal medium for microorganisms.