Long term and high resolution historical biodiversity data are required to make accurate predictions about how the biodiversity will respond to human-induced alterations in the environment. Microorganisms, vital to ecosystem functioning and services, are hard to monitor using traditional surveillance methods and are commonly not included in models of how biodiversity responds to environmental change. By using high throughput DNA sequencing, and an unbroken line of air samples collected weekly over five decades we will reconstruct biodiversity and study the presence and temporal change in a wide range of organisms (plant, animal, fungal, bacterial and viral) in the environment.