A CTD — an acronym for Conductivity, Temperature and Depth — is the primary tool for determining essential physical properties of sea water. It gives scientists a precise and comprehensive charting of the distribution and variation of water temperature and salinity depending on the depth that helps to understand how the oceans affect life.CTD measurements are carried out on the every station and via towed CTD system. The data are needed background for all studies.Passage from Hornsund to Kongsfjorden is about 20 hrs. Here there are research of plankton, bentos and chemical properties of sea water.