Summarizing the impacts of future potential global change scenarios on seawater intrusion at the aquifer scale

Abstract

Climate change afects rainfall and temperature producing a breakdown in the water balance and a variation in the dynamic of freshwater-seawater in coastal areas, exacerbating seawater intrusion (SWI) problems. The target of this paper is to propose a method to assess and analyze impacts of future global change (GC) scenarios on SWI at the aquifer scale in a coastal area. Some adaptation measures have been integrated in the deinition of future GC scenarios incorporating complementary resources within the system in accordance with urban development planning. The proposed methodology summarizes the impacts of potential GC scenarios in terms of SWI status and vulnerability at the aquifer scale through steady pictures (maps and conceptual 2D cross sections for speciic dates or statistics of a period) and time series for lumped indices. It is applied to the Plana de Oropesa-Torreblanca aquifer. The results summarize the inluence of GC scenarios in the global status and vulnerability to SWI under some management scenarios. These GC scenarios would produce higher variability of SWI status and vulnerability. Keywords Global change impacts • Adaptation measures • Seawater intrusion • Status and vulnerability • Coastal aquifer • Lumped indexThis article is a part of the Topical Collection in Environmental Earth Sciences on "Impacts of Global Change on Groundwater in Western Mediterranean Countries", guest edited by Maria Luisa Calvache, Carlos Duque and David Pulido-Velazquez.

GIS-SWIAS: Tool to Summarize Seawater Intrusion Status and Vulnerability at Aquifer Scale

“…In this paper, we describe the development of a new ArcGIS tool called GIS-SWIAS, which is the implementation of the index-based method for assessing aquifer status and vulnerability to SWI proposed by [13,15]. It helps to analyze SWI status and/or vulnerability at aquifer scale using a mixed lumped-distributed analysis.…”

“…GIS-SWIAS is an ArcGIS ArcToolbox that contains the models required to analyze SWI status and vulnerability at aquifer scale, according to the methodology described in 2 Scientific Programming previous works [13,15]. Figure 1 shows the structure of the tool, which includes inputs, steps, and models, as well as the outputs generated.…”

“…When simple interpolation is used to draw the maps used to define the indices, analyses must be limited to the historical period for which there are data. In contrast, physical process models can be applied to propagate various potential conditions and so maps can be obtained for different scenarios (e.g., alternative management scenarios or future potential CC scenarios); in this latter case, the output can be used to determine the optimum strategy and therefore support the decision-making process [15].…”

A Preliminary Lumped Assessment of Pollution Risk at Aquifer Scale by Using the Mean Residence Time. Analyses of Potential Climate Change Impacts

“…All these methods provide distributed results that can be displayed on maps where different vulnerability levels are represented. Groundwater vulnerability can also be summarized at the aquifer scale through global indices that allow for lumped results between different aquifers to be compared [11][12][13]. In order to perform a risk assessment, we need to combine hazard and pollution vulnerability maps, with the hazard being defined as the potential source of contamination derived from the human activity at the land surface [14].…”

“…Groundwater vulnerability has also been analyzed under climate change scenarios. Some studies revealed that the vulnerability is not very sensitive to climate change [12,42] because many factors considered in the index-based assessment are static. However, other authors [43] found different patterns of groundwater vulnerability to contamination between drought, average, and wet periods.…”