An experienced geographer, David was appointed in 1967, becoming Professor in 1990 and Convenor of the Department for the periods 1992-1996, 1998-2002 and 2004-2006. A geomorphologist by training, he has particular interests in applied geomorphology and environmental hazards and risk. His geomorphological research has involved studies in the UK as well as many parts of the Middle-East and Asia.

More recently his research has focused on hazard and risk management. He was co-ordinator of the UK national literature survey of landsliding funded by the Department of the Environment, which culminated in the publication of the co-authored book Landsliding in Great Britain, (HMSO, 1994), and his co-authored book Landslide Risk Assessment (Thomas Telford 2004), the 2nd edition of which was published in 2013.

His other work on risk includes collaborating in the production of chapters in the Royal Society report Risk: analysis, perception and management, and co-editing Accident and Design: contemporary debates in risk management.

In September 2016 he celebrated his 50th year in the Department and gave a talk to staff about its varied history. See photos from the talk.