Boletín de la Sociedad Geológica Mexicana Volumen 72, núm. 2, A150819, 2020 http://dx.doi.org/10.18268/BSGM2020v72n2a150819

Assessing the impact of climate change on water resources in a semi-arid area in central Mexico using a SWAT model

Monitoreo del impacto del cambio climático en los recursos hídricos en un área semi-árida de México central mediante un modelo SWAT

Chao Deng¹, Bruno Pisani², Horacio Hernández¹, Yanmei Li^1,*

¹ Engineering Division, Campus of Guanajuato, University of Guanajuato, Lascurain de Retana, 5, Center, 36000, Guanajuato, Mexico.

² Escuela Técnica Superior de Ingenieros de Caminos, Canales y Puertos, University of A Coruña, Rúa da Maestranza 9, 15001, La Coruña, Spain.

* Corresponding author: (Y. Li) This email address is being protected from spambots. You need JavaScript enabled to view it.

How to cite this article:

Deng, C., Pisani, B., Hernández, H., Li, Y., 2020, Assessing the impact of climate change on water resources in a semi-arid area in central Mexico using a SWAT model: Boletín de la Sociedad Geológica Mexicana, 72 (2), A150819. http://dx.doi.org/10.18268/BSGM2020v72n2a150819

Abstract

A Soil and Water Assessment Tool model (SWAT) was developed for the Cuenca Independencia, a 6992 km² watershed with a significant seasonal climate situated in the semi-arid highlands of Guanajuato State in central Mexico. This area is dominated by agricultural land cover (43.32 %), followed by pasture (25.7 %). Good to very good results for the coefficient of determination (R², 0.66 ~ 0.89) and the Nash-Sutcliffe Efficiency (NSE, 0.65 ~ 0.88) were obtained during both the calibration and the validation periods, while the percent bias (PBIAS) was not so good as the former indicators, but with satisfactory to very good results. According to the projections of seven general circulation models (GCM) under Coupled Model Intercomparison Project Phase 5 (CMIP5) for climate change prediction, the Cuenca Independencia may experience more precipitation and higher temperature under emission scenarios of Representative Concentration Pathway (RCP) 4.5 and RCP 8.5 for the mid-century period (2030 – 2059), as well as the end of this century (2070 – 2099), compared to the baseline condition (1970 – 1999). Potential evapotranspiration (PET) and real evapotranspiration (ET) are predicted to increase continuously. Both mean annual surface runoff and aquifer recharge are predicted to increase more rapidly under the condition of scenario RCP 8.5 than RCP 4.5. However, increasing demands of agricultural irrigation are expected to consume the larger water volume seeping into the groundwater system, making aquifer recovery unlikely through natural processes under the current water resources management framework.

Keywords: Soil and Water Assessment Tool model (SWAT), Cuenca Independencia, Semi-arid, Climate change, RCP scenario.