The Dominant Climate Change Event for Salinity Intrusion in the GBM Delta

Abstract

Salinity intrusion through the estuaries in low-lying tide-dominated deltas is a serious threat that is expected to worsen in changing climatic conditions. This research makes a comparative analysis on the impact of salinity intrusion due to a reduced upstream discharge, a sea level rise, and cyclonic conditions to find which one of these event dominates the salinity intrusion. A calibrated and validated salinity model (Delft3D) and storm surge model (Delft Dashboard) are used to simulate the surface water salinity for different climatic conditions. Results show that the effects of the reduced upstream discharge, a sea level rise, and cyclones cause different levels of impacts in the Ganges-Brahmaputra-Meghna (GBM) delta along the Bangladesh coast. Reduced upstream discharge causes an increased saltwater intrusion in the entire region. A rising sea level causes increased salinity in the shallower coast. The cyclonic impact on saltwater intrusion is confined within the landfall zone. These outcomes suggest that, for a tide dominated delta, if a sea level rise (SLR) or cyclone occurred, the impact would be conditional and local. However, if the upstream discharge reduces, the impact would be gradual and along the entire coast.

Thalassic Rotifers from the United States: Descriptions of Two New Species and Notes on the Effect of Salinity and Ecosystem on Biodiversity

“…Because small species respond quickly to environmental changes due to their rapid life cycle, they can be used also to determine the impact of habitat loss and modification due to human activities. Moreover, salinization plays a fundamental role under a climate change scenario and investigating the biodiversity of small species will provide fundamental information for long-term ecosystem biomonitoring programs [107]. As suggested by Zeppilli et al [108], this work supports the value of investigating the biodiversity of small invertebrates as ideal models to evaluate and understand the either short-or long-term effects of human activities on the surrounding environments.…”

Dynamics of salinity intrusion in the surface and ground water of Sundarban Biosphere Reserve, India

“…Sea level rise is pushing in saline sea water in most of the deltaic regions across the globe destabilizing the salinity profile in the region. Delta of Mekong, Nile, Ganga-Brahmaputra-Meghna, Irrawaddy, Red Rivers are all being impacted with salinity intrusion due to sea level rise-climate change [11][12][13][14][15][16]. Ganga-Brahmaputra-Meghna delta is facing serious salinity intrusion may be because of sea level rise as well as subsidence due to sedimentation [17].…”

Saltwater Intrusion in a Mediterranean Delta Under a Changing Climate

“…Previous studies have investigated changes in SWI in several estuaries and deltas worldwide. River discharge variability and SLR have been found to be the main factors enhancing salinity intrusion in the Yangtze, Pearl, Changjiang, Mekong, Ganges, Brahmaputra, Meghna, and Nandu rivers (Akter et al., 2019; Bricheno & Wolf, 2018; Chen et al., 2016; He et al., 2018; Hong et al., 2020; Liu et al., 2019; Smajgl et al., 2015; Zhu et al., 2018). The results of this study confirm such general behavior.…”