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Water Temperature and Cyclone Frequency in the Pacific: Implications for Pearl Farming Final, June 2008The annual sea temperature range has also been recorded in outer (37 m depth) and inner(11 m depth) waters of the Dampier Archipelago, North Western Australia. These recordsindicate that the annual range for these waters is approximately 22–30 ºC and 20–30 ºC,respectively, and that minimum and maximum readings occurred in July/August andFebruary/March (Woodside Petroleum Development Pty. Ltd, 1979a, b in Jones 2004). Itwas also noted that temperatures within shallow embayments in the archipelago can rangefrom 18 ºC in winter to 34 ºC in summer (Jones 2004).In the late 1980s/early 1990s, the Australian Institute of Marine Science installed a series ofremote weather stations on the Great Barrier Reef (GBR) in Queensland, four of whichmeasure sea temperature at a depth of ~1 m at low tide. (AIMS 2003). The mean monthlytemperature ranges, daily minimum and maximum records for these stations from theircommencement of operation until July 2000 are as follows:• Agincourt Reef (16° 2’S, 145° 49’E) - 24.0 ºC to 28.6 ºC, 22.6 ºC and 31.7 ºC;• Myrmidon Reef (18° 16’S, 147° 22’E) - 24.2 ºC to 28.9 ºC, 22.1 ºC and 29.5 ºC;• Davies Reef (18° 50’S, 147° 41’E) -23.4 ºC to 28.4 ºC; 22 ºC and 30.8 ºC;• Hardy Reef (19° 44’S, 149° 10’E) – 22.3 º C to 28.4 º C, 20.8 ºC and 30.0 ºC.The pattern of change in temperature through time was consistent across all four stationswith peaks occurring in February and troughs in August (Figure 3).In the mid-1990s, the Great Barrier Reef Marine Park Authority established a long-term seatemperature monitoring program based on in situ data loggers installed at representativesites on and adjacent to the Great Barrier Reef, on the north-east coast of Australia. Loggershave been deployed at three levels: on the reef flat at the astronomical low tide level, on theupper reef slope at depths ranging from 5-9 m and on the lower reef slope at depths of about20m.2.3.3.2 Cook IslandsWells and Jenkins (1988) indicate that the mean sea surface temperature in the Cook Islandsvaries from 25.5 °C in June to 27.3 °C in January.The SEAFRAME (Sea Level Fine Resolution Acoustic Measuring Equipment) gauge installedin Avaitu Harbour, Rarotonga in February 1993 indicates that sea temperatures since thenhave varied from a minimum of 22.0 °C in August 1998 to a maximum of 30.2 °C inFebruary 2002 (Bureau of Meteorology, Australia 2006a).2.3.3.3 FijiWells and Jenkins (1988) indicate that the sea temperature in Fiji has an annual range of 6 °C,reaches a maximum of 30 °C in summer and is always greater than 20 °C.Underwater temperature recorders were deployed at a depth of approximately 10 m at SuvaBarrier Reef in September 1996 and at Vuna Point, Taveuni in July 1997 as part of the SeawaterTemperature Monitoring Project run by the University of the South Pacific, Fiji(Cumming et al. 2000). The records from Suva Barrier Reef show that temperaturesexceeded the maximum monthly mean (MMM) of 28.5 °C for five months, remained above29 °C for 3.5 months and peaked at 30-30.5 °C between early March and early April. Similarpatterns and peak temperatures were noted at Vuna Point, Taveuni, except that the MMMwas 0.3 °C lower.The Ecology Lab Pty Ltd – Marine and Freshwater Studies Page 6