Climate modelling and drought monitoring and assessment indices case of the Lower Sebou basin, North-West Morocco

• Main Author: Oualid Hakam
• Other Authors: Baali Abdennasser
• Format: Doctoral or Postdoctoral Thesis
• Language: unknown
• Published: Zenodo 2023
• Subjects: Climate change; Drought indices; Climatic indices; Remote sensing indices; Cereal yields; Machine learning algorithms; Lower Sebou Basin; Morocco; North Atlantic; North Atlantic oscillation
• Online Access: https://doi.org/10.5281/zenodo.8183565

The Lower Sebou basin is unique in that it lies in the north of Morocco at the limit of the influence of the North Atlantic Oscillation (NAO) and under the oceanic influence, with continental effects towards the east. It also has the potential to play an important role in the socio-economic life of the region, which is dominated by agriculture, and to explain the impact of climate change in recent decades. The time series of climate data is dominated by precipitation in winter and spring and trends in December and March, determined by the Mann-Kendall test. The NAO and Mediterranean Oscillation (MO) have clearly shown their moderate to strong influence on precipitation by focusing on the NAO as a potential cause of precipitation variability, using the EOF technique. Based on climate data (1984-2016), mainly precipitation and temperature data, and taking into account the limitations and advantages of each drought index, four indices were developed, including the Standardized Precipitation Index (SPI) based solely on precipitation, the Standardized Precipitation Evapotranspiration Index (SPEI), the Drought Recognition Index (DRI) and the selfcalibrated Palmer Drought Severity Index (sc-PDSI) including potential evapotranspiration (PET), it has been confirmed that the SPI is the most suitable for detecting the duration and intensity of drought, particularly in sub-humid climate regions. However, the SPI underestimates drought changes by not taking the PET parameter into account. The four indices showed similar trends throughout the period studied, although the sc-PDSI tends to overestimate drought conditions due to its sensitivity to temperature and precipitation. Finally, using the SPI and SPEI indices to analyse seasonal trends showed significant trends, with an increase in temperature indicating increased warming in summer and a decrease in precipitation in winter. These trends are linked to the North Atlantic and Mediterranean oscillations, which are strongly influenced by cyclonic systems in the north-east ...