Sea-level projections using a NARX-NN model of tide gauge data for the coastal city of Kuala Terengganu in Malaysia.

The impact of global warming presents an increased risk to the world's shorelines. The Intergovernmental Panel on Climate Change (IPCC) reported that the twenty-first century experienced a severe global mean sea-level rise due to human-induced climate change. Therefore, coastal planners require reasonably accurate estimates of the rate of sea-level rise and the potential impacts, including extreme sea-level changes, floods, and shoreline erosion. Also, land loss as a result of disturbance of shoreline is of interest as it damages properties and infrastructure. Using a nonlinear autoregressive network with an exogenous input (NARX) model, this study attempted to simulate (1991 to 2012) and predict (2013-2020) sea-level change along Merang kechil to Kuala Marang in Terengganu state shoreline areas. The simulation results show a rising trend with a maximum rate of 28.73 mm/year and an average of about 8.81 mm/year. In comparison, the prediction results show a rising sea level with a maximum rate of 79.26 mm/year and an average of about 25.34 mm/year. The database generated from this study can be used to inform shoreline defense strategies adapting to sea-level rise, flood, and erosion. Scientists can forecast sea-level increases beyond 2020 using simulated sea-level data up to 2020 and apply it for future research. The data also helps decision-makers choose measures for vulnerable shoreline settlements to adapt to sea-level rise. Notably, the data will provide essential information for policy development and implementation to facilitate operational decision-making processes for coastal cities.

The shape of fluvial bedload gravels: A large, high-quality dataset of active-channel deposits.

Isotropic bedload gravels from an active fluvial system were collected from seven stations along the length of the Sabeto River of western Viti Levu, Fiji. Sampling was confined to clasts of Navilawa Monzonite, an intrusive rock that crops out only along the upper reaches of the river. The sampled gravels consisted of stream-bed surface material obtained from transects normal to the active channel. An additional sample was collected from an outcrop of fresh Navilawa Monzonite undergoing active physical breakdown on the side of the bedrock channel immediately adjacent to the river. A total of 883 clasts, ranging in diameter (b-axis) from 12 to 337 mm, was collected. The long (a), intermediate (b) and short (c) axis of each clast was measured, along with the diameter of the sharpest corner of the maximum projection outline (Di ) and the diameter of the maximum inscribed circle (Dk ). At six of the stations, the mass of each clast was recorded. Measurements were also made of the density of fresh Navilawa Monzonite. The dataset includes measurements of Navilawa Monzonite density and determinations of the Modified Wentworth Roundness, Maximum Projection Sphericity and Oblate-Prolate Index of each clast. At six of the stations the volume of each particle was estimated using measurements of particle mass and rock density. The repository, in Mendeley Data [1], provides a large, high-quality dataset of the shape of isotropic bedload gravels from an active fluvial system, affording information on the downstream evolution of particle shape. The dataset will be useful for sedimentologists, fluvial geomorphologists, hydraulic engineers and those concerned with fluvial bedload transport.