Stimulating investment in pearl farming in ... - World Fish Center

Water Temperature and Cyclone Frequency in the Pacific: Implications for Pearl Farming Final, June 20082.3.3.6 Solomon IslandsIn the Solomon Islands, sea surface temperatures are consistently in the upper 20s (Sulu et al.2000). The temperature is generally coolest between August and October and warmerbetween January and March. On some occasions, mean monthly sea temperatures in excessof 29.5 °C have been recorded for 4 or 5 consecutive months. Ramofafia et al.(2001) notedthat the mean monthly seawater temperatures recorded daily at the ICLARM CoastalAquaculture Centre at Aruligo to the west of Honiara, Guadalcanal over the period May1995 to December 1998 varied between 27.3 °C (September/October 1997) and 30.2 °C(February/March 1996).The SEAFRAME gauge installed at Honiara on the north-west coast of Guadalcanal in July1994 indicates that sea temperatures since then have varied from a minimum of 26.5 °C inOctober 1998 to a maximum of 31.9 °C in March 2000 (Bureau of Meteorology, Australia2006d). The SEAFRAME records also show that mean water temperatures off Honiara wereabout 2 °C below normal during the 1997/1998 El Niño.2.3.3.7 VanuatuAccording to Wells and Jenkins (1988), the water temperature in Vanuatu ranges from 24.5°C in September to 28.1 °C in February. The SEAFRAME gauge installed at Port Vila onEfate Island, however, indicates that sea temperatures since January 1993 have varied from aminimum of 23.3 °C in September 1994 to a maximum of 31.7 °C in February 2000 (Bureau ofMeteorology, Australia 2006e).2.4 SST Measurements Derived from SatellitesNumerous SST data products were considered, but only four contained composite data thatcould be easily accessed using a Personal Computer. These were the Modern AverageGlobal SST dataset produced by the US Geological Survey, the SST web atlas for the GreatBarrier Reef region produced by the Australian Institute of Marine Science and CRC ReefResearch Centre, the National Oceanic and Atmospheric Administration’s Coral Reef WatchProgram and the surface temperature search tool maintained by the Australian Departmentof Defence.2.4.1 Modern Average Global SST DatasetComparable SST data for various locations in the regions of interest were obtained from themodern average global sea-surface temperature dataset produced by the US GeologicalSurvey (Schweitzer 1993). These data are derived from weekly measurements taken by anAdvanced Very High Resolution Radiometer (AVHRR) from October 1981 to December1990 in nine separate regions of the world’s oceans. The dataset was obtained bydownloading the SST display application in format EXE Stand-alone runtime for MicrosoftWindows. This software package was used to view the monthly images for the South-eastand South-west Pacific oceans and extract estimates of the monthly SST data averagedacross the 10 year study period. It should be noted that averaging the images in this waytends to reduce the number of grid cells that lack valid data and suppresses inter-annualvariability. Data for the locations of interest were obtained by overlaying alatitude/longitude grid over the image and selecting the nearest pixel which contained SSTrecords. Data are presented for five locations distributed across the geographic extent ofmost of the South Pacific countries of interest (Figure 6). The dataset was less completearound the Solomons Islands and Vanuatu, so data for fewer locations are presented.The Ecology Lab Pty Ltd – Marine and Freshwater Studies Page 8