This dataset contains the Hydrology (HYD) data collected on Franklin voyage FR 04/2001. The voyage took place from Hobart up the Tasmanian East Coast on to Sydney, then across the Tasman sea to Wellington (New Zealand)in May 2001. This dataset has been processed and archived within the CSIRO Marine and Atmospheric Research Data Centre in Hobart. Additional information regarding this dataset is contained in the cruise report for this voyage and/or the data processing report (as available). Franklin on-voyage hydrology data are typically obtained from water samples collected in Niskin bottles at various depths during each CTD cast. Parameters measured normally comprise temperature, salinity, dissolved oxygen, phosphate, nitrate, silicate and nitrite.