The data set comprises measurements of temperature, salinity, oxygen, chlorophyll and nutrients from six locations near Port Erin, Isle of Man. The data collected at Port Erin breakwater (54 05.113N, 04 46.083W) and the Cypris station in Port Erin Bay (54 05.5N, 004 50.0W) are described separately in the "Port Erin (Isle of Man, Irish Sea) Temperature, Salinity and Nutrient Data Set (1904-)". The remaining four stations are described here. Data have been collected at the Resa (also known as Bayrnagh), approximately 5km east of Santon Head, Isle of Man (54 05.00N, 04 30.00W) at least once per month since 1994, with a hiatus from 2003-2006. The data comprise measurements of temperature at 0, 5, 10, 20 and 37m; salinity, dissolved oxygen, phosphate, nitrate, nitrite, silicate and ammonia at 0 and 37m; and chlorophyll-a at the surface. Total dissolved nitrogen was also measured at 0 and 37m between 1996 and 2003, while total dissolved phosphorus was measured at 0 and 37m between 1996 and June 2002. Corresponding data have been collected at Laxey Bay (54 12.00N, 04 23.00W), Ramsey Bay (54 20.47N, 04 17.47W) and Jurby Head Targets area (54 21.50N, 04 38.00W) at least once a month since 2006. Laxey Bay data comprise temperature at 0, 5, 10, 20 and 24m; salinity, dissolved oxygen, phosphate, nitrate, nitrite, silicate and ammonia at 0 and 24m; and chlorophyll-a at the surface. Ramsey Bay data comprise temperature at 0, 5, 10 and 19m; salinity, dissolved oxygen, phosphate, nitrate, nitrite, silicate and ammonia at 0 and 19m; and chlorophyll-a at the surface. Targets data comprise temperature at 0, 5, 10, 20 and 43m; salinity, dissolved oxygen, phosphate, nitrate, nitrite, silicate and ammonia at 0 and 24m; and chlorophyll-a at the surface. Prior to 2006 water samples and temperature measurements were collected using either a Nansen-Pettersen bottle with an insulated thermometer or an NIO bottle with a mercury reversing thermometer. Since 2006 an NIO bottle and a Sensoren Instrumente Systeme (SIS) RTM 4002 X digital deep sea reversing thermometer have been used. Salinity was determined by titration against silver nitrate until 1965, thereafter using inductively coupled salinometers (Plessey 6230N until June 1998; Guildline Portasal from July 1998). Nutrients are estimated colorimetrically and dissolved oxygen is determined by the Winkler technique, as outlined in Jacobsen et al. (1950). Until 2006, chlorophyll-a was estimated using the trichromatic methods recommended by SCOR-UNESCO Working Group 17. Since that year the spectroscopic methods of Aminot & Rey (2000) have been used. Dissolved nitrogen and dissolved phosphorus were measured using the persulphate digestion method adapted from Valderama (1981). The data were collected by the Port Erin Marine Laboratory (part of the University of Liverpool) until its closure in 2006. Sampling has since been taken over by the Isle of Man Government Laboratory (GAL). The data are managed by the British Oceanographic Data Centre.

The data set comprises measurements of temperature, salinity, oxygen, chlorophyll and nutrients from two locations near Port Erin, Isle of Man. Sea surface temperature has been measured at Port Erin breakwater (54 05.113N, 04 46.083W) on a twice-daily basis from 1904 to the present day, accompanied by twice-daily sea surface salinity measurements since 1965. Since 1954, further measurements have been taken at the Cypris station in Port Erin Bay, 5km west of Port Erin (54 05.5N, 004 50.0W). The Cypris data have been collected at frequencies ranging from weekly to monthly depending on season, boat availability and weather, and comprise measurements of temperature at 0, 5, 10, 20 and 37m since 1954; salinity, dissolved oxygen and phosphate at 0 and 37m since 1954; silicate at 0 and 37m since 1958; nitrate and nitrite and 0 and 37 m since 1960; chlorophyll a at 0 m since 1966; ammonia at 0 and 37m since 1992; total dissolved nitrogen at 0 and 37m from 1996-2005; and total dissolved phosphorus at 0 and 37m from 1996-June 2002. At Port Erin temperatures were recorded using a Meteorological Office issue thermometer from the mid-1900s to October 2006. Since then Vemco temperature autologgers and Star-Oddi DST CTD loggers have been deployed from the Port Erin lifeboat slip and are exchanged on an approximately monthly basis. Until November 1961 temperature was recorded in degrees Fahrenheit; these data have since been converted to degrees Celsius. At the Cypris station water samples were collected with either a Nansen-Pettersen or an NIO bottle from 1954-2005. The Nansen-Pettersen bottle was used in conjunction with an insulated thermometer, while the NIO bottle was used in conjunction with a mercury reversing thermometer. From 2006 onwards an RTM 4002 X digital deep sea reversing thermometer has been used with an NIO bottle. Salinity was determined by titration against silver nitrate until 1965, thereafter using inductively coupled salinometers (Plessey 6230N until June 1998; Guildline Portasal from July 1998). Nutrients are estimated colorimetrically and dissolved oxygen is determined by the Winkler technique. Until 2006 chlorophyll-a was estimated using the trichromatic methods recommended by SCOR-UNESCO Working Group 17. Since that year the spectroscopic methods of Aminot & Rey (2000) have been used. Dissolved nitrogen and phosphorus were measured using the persulphate digestion method adapted from Valderama (1981). The Cypris station data are frequently split into the Cypris I (D. John Slinn) data set comprising data from 1954-1992 and the Cypris II data set from 1992-present. Data from the Port Erin and Cypris stations are sometimes known collectively as the ‘Port Erin Bay’ data set. Data from Port Erin Bay form part of the Isle of Man GAL Coastal Monitoring Sites network, which is described in a separate EDMED entry. The data were collected by the Port Erin Marine Laboratory (part of the University of Liverpool) until its closure in 2006. Sampling has since been taken over by the Isle of Man Government Laboratory. The data are managed by the British Oceanographic Data Centre.