Analysis of climate variability and its linkage with large-scale climate oscillations: implications to pastoral and agropastoral livelihood resilience in Siti Zone, Somali Region, Ethiopia

Purpose The Somali Region of Ethiopia is extremely vulnerable to climate variability and its effects because of its arid and semi-arid environment. This study aims to examine precipitation and temperature from 1990 to 2020 together with climate indices. It examined the correlation between rainfall and temperature extreme indices in Aysha and Dembel Woredas and global climate indices. Design/methodology/approach Rainfall and temperature variability were analyzed using the coefficient of variation. Spatiotemporal sea surface temperature was established using the Pearson correlation method. Mann–Kendal and Sen’s slope estimator trend test were also used for trend analysis. Extreme indices were used to assess daily temperature and precipitation events that exceed or fall below specific thresholds. Drought was assessed using two multi-scalar drought indices SPI and SPEI at three-month and 12-month timescales were used to investigate drought and flood events in the Aysha and Dembel Woredas. Findings This study reveals that Aysha and Dembel in the Somali region have experienced highly variable rainfall patterns and a general decrease in rainfall, along with rising temperatures. These trends have led to severe moisture stress, resulting in potential water shortages and reduced pasture, significantly impacting pastoral livelihoods. Rainfall and temperature trends differ notably between the sites. Aysha has seen an increase in summer rainfall, whereas Dembel has faced a sharper annual decline, illustrating varied rainfall patterns across the study sites. Seasonal and annual rainfall change points indicate that in Aysha, seasonal rainfall increased in Spring 2004, Summer 2014 and Autumn 1997, with a decrease in Winter rainfall from 2008. In Dembel, rainfall declined significantly in Spring 1996, Winter 2008 and annually from 1997, with minor decreases in Autumn 1998 and Summer 2011. From 1990 to 2020, Aysha showed an increase in consecutive dry days (CDD), especially in the northeast, whereas consecutive wet days (CWD) declined in the central area. In Dembel, CDD rose uniformly, with a slight increase in CWD. In addition, Aysha saw an increase in heavy rainfall events, maximum one-day (Rx1day), five-day rainfall (Rx5days) and very wet days (R95P), particularly in the central and northeastern regions. Conversely, Dembel experienced declines in these indicators, further highlighting the site’s vulnerability to climate extremes. Practical implications The decline in rainfall and higher temperatures are intensifying moisture stress, threatening water and pasture resources vital to pastoral livelihoods. Adaptive strategies, such as sustainable water management and flexible, climate-responsive agriculture, are crucial. These findings emphasize the need for targeted interventions to enhance resilience and protect vulnerable communities facing climate extremes. Originality/value Through original research methods and unique data sets, this work offers new insights and contributes valuable, authentic perspectives to the existing body of knowledge in this field.