Tidal and Seasonal Variability Circulation Patterns in the Coral Reef System, Berau Continental Shelf, East Kalimantan

Ayi Tarya, A. J. F. Hoitink, M. van der Vegt

2018

Abstract

The present study examines tidal and seasonal circulation dynamics in the coral reefs, Berau Continental Shelf, East Kalimantan which exist multiple reef passages by using analysis field data and a three-dimensional hydrodynamic model. The predicted M2 tidal currents, velocities, salinity profiles and sea surface elevation show a good agreement with observed. The model results demonstrate the reef-scale circulation patterns on tidal to monsoonal variation. On the seasonal timescale, the circulation patterns strongly reflect the Monsoon seasonality. The coral reefs exposed by river plume when southwesterly wind prevailed. In this period, the vertical structure of salinity displays a thin stratified water column. The velocity profiles exhibit a classical estuarine circulation with outflow at the top layer and inflow at the bottom layer. For the tidal periods, the tidal currents present complex structures at the reef passages and exhibit the tidal eddies generated by irregularities reef gaps. The flow in the centre of the reef passage is often opposed to the flow near the reef boundaries. A mixed vertically water column occurs during spring tide. During neap tide, the water column structures form a thin stratified on top layer and a classical estuarine circulation for velocity profiles. At the cross-section of reef passages, the lateral velocities develop the two-cell circulation with upward flow at reef shores and an axial convergence (downward flow) at mid-reef passage during flood and reverse pattern during ebb. At the reef slope of continental shelf edge, the model results suggest an upward flow that generated by a Bernoulli effect during flood tide, which may be lifting the nutrient-rich water to the reef passage.

Paper Citation

in Harvard Style

Tarya A., Hoitink A. and van der Vegt M. (2018). Tidal and Seasonal Variability Circulation Patterns in the Coral Reef System, Berau Continental Shelf, East Kalimantan.In Proceedings of the 6th International Seminar on Ocean and Coastal Engineering, Environmental and Natural Disaster Management - Volume 1: ISOCEEN, ISBN 978-989-758-455-8, pages 9-15. DOI: 10.5220/0008372500090015

in Bibtex Style

@conference{isoceen18,
author={Ayi Tarya and A. Hoitink and M. van der Vegt},
title={Tidal and Seasonal Variability Circulation Patterns in the Coral Reef System, Berau Continental Shelf, East Kalimantan},
booktitle={Proceedings of the 6th International Seminar on Ocean and Coastal Engineering, Environmental and Natural Disaster Management - Volume 1: ISOCEEN,},
year={2018},
pages={9-15},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0008372500090015},
isbn={978-989-758-455-8},
}

in EndNote Style

TY - CONF

JO - Proceedings of the 6th International Seminar on Ocean and Coastal Engineering, Environmental and Natural Disaster Management - Volume 1: ISOCEEN,
TI - Tidal and Seasonal Variability Circulation Patterns in the Coral Reef System, Berau Continental Shelf, East Kalimantan
SN - 978-989-758-455-8
AU - Tarya A.
AU - Hoitink A.
AU - van der Vegt M.
PY - 2018
SP - 9
EP - 15
DO - 10.5220/0008372500090015