Scientists working on the ocean acidification project walk back to their labs after collecting water samples from both the fjord and the 'mesocosms' (experiment water enclosures). The Greenpeace ship Esperanza (in the background) and its crew are working with scientists from the German marine research institute IFM-GEOMAR to investigate ocean acidification, by deploying nine large mesocosms in Kongsfjord, near the Arctic scientific research station of Ny-Ålesund in Svalbard.