Professor Peter Croot is a marine biogeochemist whose research focuses on understanding the role of biogeochemical and physical processes on the concentration and distribution of trace elements and chemical species in the ocean. His work combines different strands of ocean observations (in situ and satellite, physical and biological), with laboratory studies to elucidate the kinetics and mechanisms underpinning the transformation of chemical species in the ocean from the surface to the deep. A key theme of his recent work is to combine satellite data with in situ optical measurements, nutrient and trace metal concentrations along with measured cell abundances (via flow cytometry) to examine the influence of picoplankton on biogeochemical cycles in the global ocean. Dr Croot has extensive at sea experience in the oxygen minimum zones of the Tropical Atlantic and Pacific and in the iron limited Southern Ocean (Participating in 4 iron enrichment experiments: SOIREE, SOFeX, EisenEx, EIFeX). He is a co-PI in the SFI research centre iCRAG (Irish Centre for Research in Applied Geoscience) and an active collaborator in the marine biogeochemical community through the GEOTRACES, IMBER, GO-SHIP and SOLAS communities. In April 2017 he was the Chief Scientist for the GO-SHIP repeat hydrography survey along the A02 line in the North Atlantic, this marked the first time that an Irish research vessel had undertaken an international hydrographic survey.