North West of Sabah

In Sabah waters, the coastal upwelling was documented in the northwest coast (Figure 1) during the northeast monsoon (Abbas et al., 2012). The presence of coastal upwelling in this area is usually evidenced through the presence of elevated chlorophyll-a concentrations and low water temperature (Abbas et al., 2012; Abdul-Hadi et al., 2013). According to Chang et al. (2018) strong northeasterly winds that blows along the northwest Sabah coast generate the surface cooling, which introduced strong vertical mixing in the water column and thus lead to the occurrence of upwelling in this area. Recently, Satar et al. (2020) compiled an extensive monthly climatology data obtained from three different sources and found Ekman transport and Ekman pumping as another responsible factors that generate the upwelling feature in the northwest coast of Sabah.

References

Abbas, A. A., Mansor, S. B., Pradhan, B., & Tan, C. K. (2012). Spatial and seasonal variability of Chlorophyll-a and associated oceanographic events in Sabah water. Proceedings of the 2nd International Workshop on Earth Observation and Remote Sensing Applications, EORSA 2012, (June), 215–219.

Abdul-Hadi, A., Mansor, S., Pradhan, B., & Tan, C. K. (2013). Seasonal variability of chlorophyll-a and oceanographic conditions in Sabah waters in relation to Asian monsoon – a remote sensing study. Environmental Monitoring and Assessment, 185(5), 3977–3991.

Chang, H. W. J., Francis, A. S., Dayou, J., Sentian, J., & Chee, F. P. (2018). Upwelling event characteristics of chlorophyll-a concentration in the surface layer of Sabah waters. Indian Journal of Geo-Marine Sciences, 47(12), 2532–2540.

Satar, M. N., Akhir, M. F., Kok, P. H., & Daud, N. R. (2020). Upwelling in the northwest Sabah during the northeast monsoon and its relaion with El-Niño. Research in Marine Sciences, 5(2), 681–698.