The UK SOLAS Cape Verde Atmospheric Observatory (16.848N, 24.871W) exists to advance understanding of climatically significant interactions between the atmosphere and ocean and to provide a regional focal point and long-term data context for SOLAS field campaigns. The observatory is based on Calhau Island of São Vicente, Cape Verde in the tropical Eastern North Atlantic Ocean, a region which is data poor but plays a key role in atmosphere-ocean interactions of climate-related and biogeochemical parameters including greenhouse gases. It is an open-ocean site that is representative of a region likely to be sensitive to future climate change, and is minimally influenced by local effects and intermittent continental pollution. Measurements began at the site in October 2006 and are continuing to this day. Note that only observations for the period 2006-2009 were used in the context of the SOLAS project.