Dynamic of ENSO towards upwelling and thermal front zone in the east coast of Peninsular Malaysia

• Published in: Acta oceanologica Sinica 2019, Vol.38 (1), p.48-60
• Main Authors: Daud, Nurul Rabitah, Akhir, Mohd Fadzil, Muslim, Aidy M.
• Format: Article
• Language: English
• Subjects: Climatology; Cloud cover; Coastal fronts; Coastal upwelling; Coastal zone; Coasts; Cold water; Data; Earth and Environmental Science; Earth Sciences; Ecology; El Nino; El Nino phenomena; El Nino-Southern Oscillation event; Empirical analysis; Engineering Fluid Dynamics; Environmental Chemistry; Fish industry; Fisheries; Fishery industry; Imaging techniques; Marine & Freshwater Sciences; MODIS; Ocean circulation; Ocean dynamics; Oceanography; Oceans; Orthogonal functions; Sea surface; Sea surface temperature; Southern Oscillation; Spatial data; Spectroradiometers; Stratification; Surface temperature; Temperature; Temperature effects; Thermal fronts; Upwelling; Water circulation; Water column; Water stratification; Water temperature; Wavelet analysis; Wavelet transforms
• ISSN: 0253-505X; 1869-1099
• DOI: 10.1007/s13131-019-1369-7

The El Niño Southern Oscillation (ENSO) is a natural phenomenon that relates to the fluctuation of temperatures over the Pacific Ocean. The ENSO significantly affects the ocean dynamics including upwelling event and coastal front. A recent study discovered the seasonal upwelling in the east coast of Peninsular Malaysia (ECPM), which is significant to the fishery industry in this region. Thus, it is vital to have a better understanding of the influence of ENSO towards the coastal upwelling and thermal front in the ECPM. The sea surface temperature (SST) data achieved from moderate resolution imaging spectroradiometer (MODIS) aboard Aqua satellite are used in this study to observe the SST changes from 2005 to 2015. However, due to cloud cover issue, a reconstruction of data set is applied to MODIS data using the data interpolating empirical orthogonal function (DINEOF) to fill in the missing gap in the dataset based on spatial and temporal available data. Besides, a wavelet transformation analysis is done to determine the temperature fluctuation throughout the time series. The DINEOF results show the coastal upwelling in the ECPM develops in July and reaches its peak in August with a clear cold water patch off the coast. There is also a significant change of SST distribution during the El Niño years which weaken the coastal upwelling event along the ECPM. The wavelet transformation analysis shows the highest temperature fluctuation is in 2009–2010 which indicates the strongest El Niño throughout the time period. It is suggested that the El Niño is favourable for the stratification in water column thus it is weakening the upwelling and thermal frontal zone formation in ECPM waters.