Water and and migration: the nexus between water availability for food and livestock production, hydroclimatic changes, and environmental migration

Water is an essential natural resource for establishing and sustaining life, ecosystems, and economic development on earth. Despite humankind's rapid development and technological achievements, millions still lack access to food, energy, and water, and climate change exacerbates the pressure on limited natural resources. As a result, water governance is increasingly recognized as a critical factor in mitigating human-water problems and their socio-political consequences, including forced migration. When water access and quality deteriorate due to mismanagement or inadequate governance, communities may face heightened displacement risks, particularly in regions already grappling with environmental stressors like droughts, water scarcity, and food insecurity. Our study in the following chapters explores the nexus between water resources availability for food and livestock production, hydroclimatic changes, and environmental migration through a socio-hydrological framework that could be used to inform future water governance approaches addressing complex, multilayered and multicausal human-water problems focusing on East Africa. Communities in East Africa have been quite resilient against changes in rainfall patterns. However, when these changes spread to activate exacerbating factors, a holistic view of environmental drivers and their regional interactions is necessary. Our study focused on the crop and livestock production sectors to understand how water limitations associated with drought, agricultural water scarcity, and the consequent food insecurity can relate to environmental migration patterns. The nexus between these indicators and environmental migrations in the region plays an important role in shaping the response of farmers and agropastoralist communities, which account for roughly 80% of the population, to either adapt to the changing environment or depart. Environmental threats to shelter, livelihoods, and food security are often considered push factors for intra-African human migration. Research in this field is often fragmented into a myriad of case studies on specific subregions or events, thus preventing a more comprehensive understanding of the phenomenon. Our research begins with an introductory chapter overviewing some work on water governance and human-water problems. It focuses on the multidimensionality of water’s nature in shaping sustainable development in all sectors by analyzing influential actors working to solve the problems for the past two decades. Then, we proceed to more specific works on the relationship between hydroclimatic changes and migration across a broader study area, Sub-Saharan Africa, and close examination of East Africa for specific mechanisms by which hydroclimatic factors influence migration trends in Somalia and Ethiopia. Despite the growing interest in environmental migrations observed in scholarly literature and the media, the nexus between hydroclimatic drivers and human displacement, conclusive empirical evidence of the relationship remains poorly investigated, particularly concerning the need for more comprehensive data and analyses to understand the specific mechanisms by which environmental factors influence migration decisions and patterns. Furthermore, the following chapters investigate the spatial interaction between the three indicators of the scarcity of water that highly influence East Africa's food and livestock production and primary internal displacement reasons: drought, agricultural water scarcity, and food insecurity. We draw insights from various sources of ground data from our study countries and combine them with remotely sensed climate data, multiple rounds of surveys on environmental migrants and internally displaced people, and socioeconomic development pathways (SSPs) from the Regional Climate Model. We used metanalysis, Qualitative Comparative Analysis, statistical correlation, multivariate spatial autocorrelation and clustering method, and agrohydrological and Persistence Index models to disentangle the complex multicausal phenomena of environmental migration and examine the multifaceted challenges posed by slow onset hydroclimatic extremes on environmental migration by taking account of the time lag of events exhibited before the people feel their effect. Understanding and predicting societal difficulties during global hydroclimatic and environmental changes is crucial, as well as the degree of susceptibility and the societal resilience to adapt and mitigate these changes. Therefore, in the end, we leveraged the above-mentioned methodological approaches to anticipate high-risk regions susceptible to future environmental migration or internal displacement based on climate change (RCP) and development scenarios (SSP). The results across these chapters show that the complex web of causal links are the main drivers of environmental migration in Sub-Saharan Africa, while individual extreme or slow-onset events with high intensity and severity are very critical migration inducers. However, non-environmental underlying factors play a significant role by exposing the population to cumulative environmental changes and hindering their resilience. Multivariate spatial analysis and clustering provide the co-occurrence of scarcity of water indicators is found to be a statistically significant indicator and predictor of human displacement in the region. These results demonstrate that understanding and identifying areas prone to environmental migration flux depend highly on a cumulative driver approach that accounts for the persistence effect (slow onset events) rather than individual drivers. Overall, the research highlights that addressing the multifaceted layers of environmental migration drivers in East Africa requires integrating climate change and migration into policies across critical sectors like agriculture, water, livestock, forestry, and infrastructure to support adaptation.