Future projection of droughts in Morocco and potential impact on agriculture

Abstract

The present study evaluates the future drought hazard in Morocco using a Multi-Model Ensemble (MME) approach. First, the artificial neural network-based MME is constructed using the General Circulation Models (GCMs) from the Climate Models Intercomparison Project phase 6 (CMIP6) which are most successful in representing the historical temperature and precipitation values. Next, the future changes in the precipitation, Potential EvapoTranspiration (PET) calculated using temperatures data, aridity index, and drought indices calculated via the Standardized Precipitation Evapotranspiration Index (SPEI) values were projected for the historical period 1980-2014, near future 2025-2050, mid future 2051-2075, and far future 2076-2100. The obtained results indicate that there will be a decrease in values of the precipitation and an increase in values of the PET, leading to an increase in aridity risk for Morocco. The future projections using the SPEI results show that the average index values will mostly be in the drought zone, indicating that the drought severity will increase. The spatial analysis of SPEI values in different regions of Morocco demonstrates that the northern part of the country has relatively more drought occurrences, and drought severity tends to increase with each passing period. The study also reveals that drought severity will significantly increase after 2050 in the Shared Socio-economic Pathways 5-8.5 (SSP5-8.5) scenario. The research concludes that the increase in drought severity will significantly impact Morocco's water resources, agriculture and food security among others.

Keywords: Artificial neural network; CMIP6; Climate change; Drought analysis; Projections.