Kajian klorofil-a dan nutrien serta interelasinya dengan dinamika massa air di perairan barat Sumatera dan Selatan Jawa – Sumbawa

Abstract

Data for this research consists of: (1) wind data from European Center for Medium Range Forecast (ECMWF) in the period of 1990-2002; (2) Sea Surface Temperature (SST) data from National Oceanographic and Atmospheric Administration (NOAA) of 1990-2005 and also from Moderate Resolution Imaging Spectro Radiometer (MODIS) AQUA of 2002-2005; (3) chlorophyll-a data from SeaWifS image of 1997-2005 and from MODIS AQUA of 2002-2005 as well; (4) the sea level anomaly data of 2001-2005 from TOPEX/POISEDON, European Remote Sensing Satellite (ERS-1 and ERS-2); (5) nitrate and chlorophyll data from NOBM (NASA Ocean Biogeochemical Model) Assimilated Dayled Global Products of 1997-2005; (6) CTD data from the expedition of Baruna Jaya I in 1990 and (7) the archives of World Ocean Data – National Ocean Data Center (WOD-NODC). All of the collected data were utilized to analyze and investigate characteristics and dynamics of water mass by using the Ekman Transport and Ekman Pumping methods. Also, the analyses included the interrelationship between the dynamics of water mass and distribution of nutrient and chlorophylla in the waters of West Sumatera and South Java – Sumbawa. Results of the Ekman Transport analyses showed that water mass transported from beach towards off-shore was the larger during the East Season in the West Java and around Sunda strait than that of the West Sumatera and the South of Central Java – Sumbawa. The Ekman Pump analysis showed that upwelling process occurred at along side of West Sumatera and South Java – Sumbawa waters from June to October. The highest level of upwelling was found in the South of Central Java – East Java. Indications of the upwelling occurred in the East season were of the lower of SST, and sea level anomaly under sea surface level. In addition, the concentration of chlorophyll-a, nitrate, phosphate, and silicate increased. The more intensive upwelling occurred in the south of Central Java – East Java was because of Ekman Transport moving away from beach, and perhaps due to the bigger gradient of wind stress on each component and influence of South Equator Current as well.