Investigation of transient sea level rise impacts on water quality of unconfined shallow coastal aquifers

Abstract

This study analyzes the impacts of 1 m gradual and instantaneous sea level rise combined with pumping activity on seawater wedge toe location in a shallow coastal aquifer located in the southern shores of the Caspian Sea. The gradual sea level rise scenario investigates the transition variation of seawater wedge toe due to linear and parabolic between the years 2015 and 2100. Moreover, the maximum value of saltwater intrusion due to variations in hydraulic conductivity and aquifer's recharge rates is analyzed and compared with flux-controlled and head-controlled boundary condition systems. A tree model is also applied to develop a linear regression between the sea level rise and aquifer parameters derived from different real coastal aquifers in the literature. The results indicate that 1 m gradual sea level rise in the study area by the end of the year 2100 considering all 1320 pumping wells leads to a 6.5% depletion of freshwater volume. The results also show that the peak saltwater intrusion rate during nonlinear gradual sea level rise rises with increasing the aquifer depth and horizontal hydraulic conductivity and the time to reach the saltwater intrusion peak rate considering the current recharge rate of an aquifer is about 48 m. The maximum saltwater intrusion lengths estimated by the tree model are 48 m and 10.42 m for head-controlled and flux-controlled boundary conditions, respectively, indicating that the saltwater intrusion in the aquifer due to instantaneous seal level rise is closer to head-controlled boundary conditions.

Sea level prediction using ARIMA, SVR and LSTM neural network: assessing the impact of ensemble Ocean-Atmospheric processes on models’ accuracy

“…There has been an unprecedented rise in global sea levels, with devastating physical and socioeconomical effects on the coastal communities (Nicholls and Cazenave 2010;Nidhinarangkoon et al 2020;Ranjbar et al 2020;Schaefer et al 2020;Shi et al 2020;Stammer et al 2013). Since the start of the 20th century, the Global Mean Sea Level (GMSL) has risen by about 16-21cm, with more than 7 cm of this occurring since 1993 (Global Change Research Program 2019;Jevrejeva et al 2016;Yi et al 2017).…”

“…Shoreline changes, rising frequency and intensity of flooding, erosion, change in coastal aquifers quality and groundwater are some of the physical impacts of SLR on coastal communities (A. Cazenave and Llovel 2010;Church and White 2011;Nicholls and Cazenave 2010;Ranjbar et al 2020;Werner and Simmons 2009). The socio-economic consequences of SLR include water and soil quality degradation, loss of lives, properties, damage to infrastructures, and depletion of agricultural resources (Ghazali et al 2018;IPCC, 2013).…”

Mean Sea Level: The Effect of the Rise in the Environment

“…The major supplier of freshwater globally is groundwater and freshwater globally is of limited amount. Unfortunately, this very little amount of freshwater becomes subjected to salt/seawater intrusion (Loáiciga et al 2012;Werner et al 2013;Sharip et al 2019;Ranjbar et al 2020). Sea level rise and tidal fluctuations induced by global warming will result in increased saltwater intrusion into freshwater bodies, invariably affecting groundwater quality (Li et al 2001;Pool et al 2014;Sefelnasr and Sherif 2014;Kuchaksaraei et al 2019;Ranjbar et al 2020).…”

“…Unfortunately, this very little amount of freshwater becomes subjected to salt/seawater intrusion (Loáiciga et al 2012;Werner et al 2013;Sharip et al 2019;Ranjbar et al 2020). Sea level rise and tidal fluctuations induced by global warming will result in increased saltwater intrusion into freshwater bodies, invariably affecting groundwater quality (Li et al 2001;Pool et al 2014;Sefelnasr and Sherif 2014;Kuchaksaraei et al 2019;Ranjbar et al 2020). Recently, some studies have shown that the predicted sea-level rise by the year 2100 will be between 0.2m and 0.8m, which will cause extensive flooding of coastal regions (Vermeer and Rahmstorf 2009;IPCC 2013Ranjbar et al 2020.…”

Numerical Modeling of Saltwater Intrusion in the Rmel-Oulad Ogbane Coastal Aquifer (Larache, Morocco) in the Climate Change and Sea-Level Rise Context (2040)

“…Abd-Elhamid et al [30] examined the individual and combined effects of predicted SLR and over-pumping on SWI using a coupled transient density-dependent finite element model to simulate SWI in the Gaza aquifer. Ranjbar [31] analyzed the effects of a 1 m gradual and immediate SLR associated with pumping activities on the location of seawater wedge toe in a shallow coastal aquifer on the Caspian Sea's southern shores. Essink and Schaars [32] developed a model to simulate GW flow, heat and salinity distribution, and seepage and salt load flux into the surface water system.…”