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Propagation of Upwelling on Western-Coast Sumatra During Madden-Julian Oscillation Event

Haryanto Y. D., Fitrianti N., Hartoko A., Anggoro S., Zainuri M.

Journal of Ecological Engineering

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2018

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Vol. 19, nr 1

122--128

EN

Madden-Julian oscillation (MJO) is an atmospheric oscillation due to atmospheric phenomenon that occurs due to the uniformity of solar energy received at the surface of the earth, MJO is a natural occurrence in the seaatmosphere system. When the MJO is active, in general there will be a disturbance in the upper air which is then followed by an anomaly at sea surface pressure causing the changes in the wind on the surface. The changes in the surface wind affect the sea surface currents which then cause the occurrence of coastal upwelling downwelling. The upwelling process itself is a process whereby a sea mass is pushed upward along the continent, when the beach is to the left of the wind direction, the ecological transport leads to the mass of water away from the coast. As a result, there is a mass vacuum (divergence) in the coastal area. This mass void will be filled by the mass of water from the inner layer that moves to the surface. Indonesian territory itself is passed by MJO in phases 3, 4 and 5, while for Sumatra region is passed by MJO phase 3 and 4. This research aims to identify the propagation of coastal upwelling during MJO on the west coast of Sumatera, therefore the data of geopotential height, surface pressure sea ( MSLP), zonal and meridional components and sea surface temperature are used to analyze how the MJO effect on the coastal upwelling occurs in the research area. The analysis was conducted in June, July and August by comparing the atmospheric conditions at the time of strong MJO in phases 3 and 4 with normal viewing of anomaly geopotential height and MSLP and then seeing the anomaly surface wind changes from zonal wind (u) and meridional wind (v) and changes in SST in Sumatra region. The result shows that there is a change of GH and MSLP when MJO passes the west coast of Sumatra and then follows the change in the value of u and v and SST to identify the upwelling, while the anomaly change negative SST does not occur when MJO is active but has time lag (lag). In this analysis it was found that SST anomaly occurs when the anomaly changes in both the upper and surface water occurring after 5 days in phases 3, 4 and 5.

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Effects of coastal upwelling on picophytoplankton distribution off the coast of Zhanjiang in South China Sea

Wu M-L., Wang Y-S., Wang D.-X., Dong J-D.

Oceanological and Hydrobiological Studies

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2014

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Vol. 43, No. 3

283--291

EN

Coastal upwelling occurred along the west coast of Guangdong in the northern South China Sea during the summer of 2006. The effects of upwelling on the vertical and horizontal distributions of Prochlorococcus and Synechococcus were investigated. A distinct vertical temperature difference between the surface water and water at a depth of 30 m was observed in the coastal upwelling region. There was a clear spatial variability of temperature, and an increasingly obvious horizontal gradient was created from the coast to offshore waters. Picophytoplankton communities observed from the coast to offshore waters were significantly different. In the coastal upwelling waters, the picophytoplankton community was dominated by Synechococcus within the euphotic zone. Prochlorococcus dominated the picophytoplankton community in the euphotic zone in the non-upwelling region. This difference in the picophytoplankton community structure was due to different hydrodynamics. The results of canonical correspondence analysis demonstrate that temperature, salinity, and phosphate concentration may be important factors affecting the distribution of Prochlorococcus and Synechococcus.

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Upwelling dynamics in the Baltic Sea studied by a combined SAR/infrared satellite data and circulation model analysis

Gurova E., Lehmann A., Ivanov A.

Oceanologia

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2013

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No. 55 (3)

687--707

EN

Data from the space-borne synthetic aperture radar (SAR) aboard the Envisat satellite and MODIS spectroradiometers on board the Terra/Aqua satellites, and the high resolution Sea Ice-Ocean Model of the Baltic Sea (BSIOM) have been used to investigate two upwelling events in the SE Baltic Sea. The combined analysis was applied to the upwelling events in July 2006 along the coasts of the Baltic States, and in June 2008 along the Polish coast and Hel Peninsula. Comparisons indicated good agreement between the sea surface temperatures and roughness signatures detected in satellite imagery and model results. It is shown that BSIOM can simulate upwelling events realistically. The utilization of modelled hydrodynamics and wind stress data together with SAR and SST information provides an extended analysis and deeper understanding of the upwelling processes in the Baltic Sea. During the active phase of upwelling when the wind is strong, the resulting coastal jet is controlled by vorticity dynamics related to depth variations in the direction of the flow. Typical upwelling patterns are related to the meandering coastal jet and thus associated with topographic features. The longshore transport of the coastal jet is of the order of 104 m3 s-1, and the offshore transport at the surface is of the order of 103 m3 s-1,, which respectively correspond to the total and largest river runoff to the Baltic Sea.

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Influence of coastal upwelling on chlorophyll a concentration in the surface water along the Polish coast of the Baltic Sea

Krężel A., Szymanek L., Kozłowski Ł., Szymelfenig M.

Oceanologia

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2005

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No. 47 (4)

433-452

EN

Space-time variations in chlorophyll a (Chl a) concentrations in the surface water of upwelling regions along the Polish coast of the Baltic Sea were analysed. Carried out between 1998 and 2002 in the warmer season (from April till October), the measurements were targeted mainly at the Hel upwelling. Satellite-derived sea surface temperature (AVHRR) and Chl a data (SeaWiFS) were used. Generally speaking, the Chl a concentration increased in the upwelling plume, except along the Hel Peninsula, where two scenarios took place: a reduction in Chl a concentration in spring and an increase in autumn.