Roy Chester recently retired from his post as the Proudman Professor of Oceanography in what was then the Department of Earth Sciences at the University of Liverpool. During his career he wrote over 140 scientific publications, and in 1999 was awarded the Hans Pettersson Bronze Medal by the Royal Swedish Academy of Sciences. He is also the author of ‘Furnace of Creation, Cradle of Destruction - A journey to the birthplace of Earthquakes, Volcanoes and Tsunamis‘. Tim Jickells is a marine biogeochemist with over 150 publications. He has been based at the University of East Anglia for more than 25 years and before that worked in Bermuda and Scotland. His main research interests are in atmospheric inputs to the oceans and coastal nutrient cycling and his field work has included tropical, temperate and polar environments. He was awarded the Challenger medal in 2006.