Rick Battarbee (1947-) is a palaeolimnologist whose studies of lake sediments deposited over recent timescales have transformed understanding of the timing and causes of environmental changes, including eutrophication and acidification. In particular, he has developed the use of diatom analysis – the study of siliceous remains of organisms called diatoms found in lake sediment cores – to deduce past changesin the composition (acidity, nutrient content, etc.) of lake water. Using this and other palaeoecological and historical-geographical techniques, he has been able to make decisive arguments in debates over the sources of pollution and causes of environmental problems, such as acid rain and climate change. Following formative early work in Northern Ireland, based at the New University of Ulster, Rick has spent most of his career at University College, London where he is now an Emeritus Professor in the Department of Geography’s Environmental Change Research Centre.