Adrià Rubio-Martín (Spain) 1; Alberto García-Prats (Spain) 1; Héctor Macián-Sorribes (Spain) 1; Patricia Marcos-García (Spain) 1; Manuel Pulido-Velázquez (Spain) 1
1 - Instituto Universitario de Ingeniería del Agua y del Medio Ambiente (IIAMA-UPV)
In this contribution, we have developed a system dynamics (SD) model for the Jucar River Basin (located in eastern Spain) and have assessed the impact of climate change in the system, as well as the effect of a combination of adaptation strategies. The system has three main reservoirs, which allows for a multiannual management of the storage that compensates the highly variable inflows. The model consists of seven interlinked subsystems:
- Topology of the system network.
- Mancha Oriental aquifer and stream-aquifer interaction with the Jucar River.
- Monthly operating rules of each reservoir.
- Monthly urban, agricultural and environmental water demands.
- State index of the system and drought mitigation measures.
- Climate change adaptation strategies.
- Economic subsystem.
The comparison between observed and simulated values showed that the model provides a good representation of the historical reservoir storage and total water deficits. The interdisciplinary and open nature of SD allows adding new variables and dynamics to the model that are rooted on non-physical system components, including management, political, legal and social features. The structure-behaviour link of SD models is suitable for the analysis of how small changes on the system might affect the behaviour of the system as a whole. This allows testing how the system will respond under varying sets of conditions, including climate change scenarios. Several climate change scenarios have being tested through the input of water inflows corresponding to different climate scenarios. To obtain the future precipitation and temperature time series, we used the output of 11 combinations of Global Climate Models (GCMs) and Regional Climate Models (RCMs) considering two different scenarios (RCP 4.5 and RCP 8.5). Future inflows were computed using these climate variables (previously bias-corrected through a quantile mapping technique) as inputs to a hydrological model.
The adaptation plans for the Jucar system follows two approaches: a) increasing the amount of water available by reusing, desalinating or pumping water; b) control the demand by changing land use, changing crops or modernizing old irrigation systems. The evaluation of adaptation strategies has being executed for the whole basin in different combinations. An economic assessment of the impact of these strategies was also carried out for the main economic activities existing on the basin.
The European Research Area for Climate Services programme (ER4CS) supports this study under the INNOVA project (grant agreement: 690462).