The dissolved oxygen concentration of seawater can indicate the type of life which may be present or if pollution has occurred. Dissolved oxygen levels are also affected by salinity and temperature. The Rugged Dissolved Oxygen (RDO) probe features automatic temperature compensation for the most accurate oxygen measurements. The RDO meter compensates readings for the sample salinity. See Electrode Log 54 Correcting DO Measurement for Salinity for instructions on salinity measurements and corrections.