The internal computer network will look after all data acquisition and storage process. According to the type of mission, some data will be immediately sent to the control station, so that scientists can evaluate the work that is being done, and the eventual need of redefining any mission parameters. The amount of data that is sent on real time to the control station can be defined by the operators, and is only limited by the cost and time required for that transmission. All the data can be retrieved when she returns to harbour. That only depends on the mission specification and cost of transmissions.
Satellite transmission are expensive but radio links are cheap.
If the vessel is within the range of radio links, then she will probably be in permanent contact. The vessel will have navigation instruments to tell the computers its position. Ocean surface layer . Caravela will measure temperature, salinity, and chlorophyll at the upper layer of the ocean. Ocean deep layers .