Modelling tidal river salinity in coastal Bangladesh

Abstract

Understanding how changing climate may affect future salinity levels is important for ecosystem services within the delta. Observations of tidal river salinity in Bangladesh are limited so a field survey of salinity levels and river soundings were undertaken providing calibration for a hydrodynamic model. Modelled changes in salinity levels have a pronounced spatial pattern. The saltiest river waters continue to be found in the western section of the delta, including the Sundarbans. The largest changes are projected in the central estuaries, where rising sea levels move the saltwater front further inland, increasing salinity levels. In the eastern section, increased river flow and rising sea levels are more balanced, and little change is anticipated in future salinity at the mouth of the Meghna River.