Investigation on influence of RCP-based climate scenarios on the hydrodynamic and morphodynamic changes during extreme events

Abstract

The hydrodynamics and morphodynamic changes induced by climate change is a serious threat to a coastal community, in which researches are scanty. This study describes how a tropical cyclone and its associated surge, wave and morphological changes would behave in future with persistently changing Representative Concentration Pathway (RCP)-based climate change scenarios. For the prediction of morphodynamics, to fully capture the tidal effects on waves and vice versa, TELEMAC-2D, TOMAWAC and SISYPHE modules are internally coupled with each other. In this study, we considered three scenarios of RCP (4.5, 6.0 and 8.5) in the Near-Future (2025–2045) and Far-Future (2065–2085). To endorse the efficacy of the model in coupled environment, the predicted wind speed, surface elevation and wave climate for an extreme event is compared with the field conditions. The result shows that, in RCP 6.0 and RCP 8.5 in far future, the effects of climate change in terms of maximum wind speed and maximum significant wave height increased in an order of to 10% to 15% and 9% to 14%, respectively. The effect of climate change scenarios in storm surge and current magnitudes does not follow any particular trend. The bed level changes for future scenarios (RCP 6.0 and RCP 8.5) in the area of assessment is doubled from the Control run. The numerical modeling results from this study conveys fresh visions about the effect of tropical cyclone on environmental parameters, in the present and future climate scenarios.