Tim leads a group across the University of Oxford exploring proposed geoengineering techniques and the governance mechanisms required to ensure that any research in this field is undertaken in a responsible way.

He has investigated in detail one potential geoengineering technique, that of adding alkalinity to the ocean as a way of enhancing its capacity to act as a carbon sink and to counteract the effects of ocean acidification.

He is also a co-author of the Oxford Principles – a set of draft principles for the conduct of geoengineering research, which have been adopted as policy by the UK government.