Temperature Variability at Senunu Bay, West Sumbawa

Abstract

Senunu Bay is a very dynamics and unique waters. The purposes of this study are to assess the character of the temperature and its relation to regional processes in the Senunu Bay, and to analyze its variability. The result showed that there was a clear vertical stratification. The thickness of mixed layer is about 39-119 m and was represented by the 27˚C isotherm. The thickness of thermocline layer is about 83-204 m and represented by 14 – 26 ˚C isotherms, and the deep layer from the thermocline lower limit to the sea bottom was represented by less then 13 ˚C isotherms. Temperature and the thickness of each layers varied according to the season in which during the North West Monsoon the temperature was warmer and the mixed layer was thicker than those at the South East Monsoon. In the South East Monsoon, the thermocline layer rise about 24 m. In 2001, 2006 and 2009 was alleged as a La Nina period. In 2003 and 2008 thickening of mixed layer occurred in transition season I and was associated with Kelvin Wave. In 2002 and 2004 was alleged as an El Nino period and in 2007 was believed to be related with positive IODM. The temperature spectral density of mixed layer and thermocline was dominated by annual period fluctuation. The cross-correlation between wind and temperature showed a significance cross-correlation in the annual period while SOI and temperature significance cross-correlation occurred at the period of annual; DMI and temperature significance cross-correlation at the period of semi-annual, intra-annual and annual.