Impacts of Sea Level Rise and River Discharge on the Hydrodynamics Characteristics of Jakarta Bay (Indonesia)

Abstract

Jakarta city has been vulnerable to sea level rise and flooding for many years. A Giant Seawall (GSW) was proposed in Jakarta Bay to protect the city. The impacts of sea level rise and river discharge on the tidal dynamics in Jakarta Bay and flooding areas in Jakarta city were investigated using the finite-volume coastal ocean model (FVCOM). Model results showed that the bay is diurnally dominated by the K1 tidal component. The diurnal tides propagate westward, while the semidiurnal tides propagate eastward in the bay. The rise of sea level increases the diurnal tidal component and the inundation areas due to the increased tidal forcing: when considering a sea level rise of 0.6 m, the K1 amplitude increases by ~1% (0.25 cm) near the coastline and the current magnitude increases by 16.6% (0.05 m/s). The inundation area increases with the sea level rise in the low land elevation areas occurring near the coastlines: the inundation area increased by 29.68 km2 (7.1%) with a sea level rise of 0.6 m. The increase of river discharge amplified the diurnal tidal component as well as the inundation areas at the river mouth due to increased fluvial forcing: if 10 times the mean river discharge occurs, the K1 amplitude increases by ~1% (0.25 cm) and the current magnitude increases by 100% (0.4 m/s), and the inundation areas increase by 26.61 km2 (6.2%). The K1 tidal phase remains almost unchanged under both the sea level rise and river discharge conditions. The combined increase of sea level rise and the river discharge amplifies the inundation areas and the tidal currents due to increased tidal and fluvial forcing. The construction of GSW would decrease the tidal prism and dissipation effects of the bay, thus slightly increasing the K1 amplitude of the tidal level: by less than 1% (0.2 cm). There would be no significant change of phase lag for the K1 component. Although this study is site specific, the findings could be applied more widely to any open-type bays.

Sea level rise and climate change acting as interactive stressors on development and dynamics of tropical peatlands in coastal Sumatra and South Borneo since the Last Glacial Maximum

“…From the Last Deglaciation to the Early Holocene, sea level in Sundaland rose rapidly (Geyh et al, 1979; Sathiamurthy & Voris, 2006). This likely caused an impeded drainage and rising groundwater level in the areas of present‐day Borneo, Sumatra and the Malaysia Peninsula (Sathiamurthy & Voris, 2006; Surya et al, 2019). In combination with increasing precipitation in Borneo (Section 4.2.2), it led to waterlogged conditions in Katingan, which allowed peat to accumulate rapidly (Dommain et al, 2011, 2014).…”

“…From the Last Deglaciation to the Early Holocene, sea level in Sundaland rose rapidly (Geyh et al, 1979;Sathiamurthy & Voris, 2006). This likely caused an impeded drainage and rising groundwater level in the areas of present-day Borneo, Sumatra and the Malaysia Peninsula (Sathiamurthy & Voris, 2006;Surya et al, 2019).…”

Assessment of Sensitivity and Validity Hydrodynamic Model in Cisadane Using Delft3d Flow Model

“…The skill range varies in a similar pattern for all domains; as we can see in 10 km 2 domain, the index of agreement (skill) range is 0.975 to 0.988, while the 20 km 2 domain is 0.965 to 0.987 next one, the 25 km 2 domain is 0.976 to 0.987, and the last is the 30 km 2 domain in the 0.971 to 0.987 range. Surya et al, (2019) proposed a statistical method for assessing model skill in the context of verification. This skill represents the degree of divergence between prediction and observation data.…”

“…Therefore, it can be concluded that the effect is negligible due to employing a hydrodynamic-only modeling scheme. A study by Surya et al (2019) demonstrates that the influence of river discharge affects the tidal component solely at the river mouth, while the overall study area remains unaffected by this river discharge. However, it should be noted that this boundary may exhibit significant alterations if a sediment module is incorporated into future studies.…”

“…Sea level and river discharge affect tidal dynamics and inundation areas in Jakarta Bay. This research was carried out by Surya et al (2019) using the finite volume coast model (FVCOM). Hydrodynamic modelling using MIKE 21 and Delft3D has been carried out in the Jakarta Bay area, and it is found that reclamation has no significant effect on current patterns (Jasmin et al, 2019;Ihsan, 2020;Nugroho and Magdalena, 2020).…”