Modelling Heat Transport in Coastal Aquifer Incorporating Tidal Effects

Heat transport has been recognized as a hydrologic tracer to indentify surface water infiltration and the exchange of surface water and groundwater. This paper investigates the heat transport with groundwater movement in coastal aquifers under tidal conditions. The aquifer vertically terminates at coastline with a thin submarine outlet-capping. Firstly, the time averaged analytical solution of tide-induced groundwater head fluctuations in the aquifer is incorporated into the governing equations of heat transport through calculating the Darcy velocity of groundwater flow. Then the time-averaged solution of heat transport in the aquifer is derived. The sensitivity analysis was conducted to determine the effects of model parameters on heat transport, which shows that the temperature in aquifer deceases with the decrease of the temperature decay coefficient (negative value). The comparisons of present solution and previous solution indicated that the outlet-capping maybe services as a temperature buffer storing heat in coastal aquifers. Our findings provide insights into the management of coastal ecohydrological systems and the heat flow regime in coastal areas responding to global climate change, urbanization and costal structures.