Abstract
Climate change is causing extreme hydrological events in Central Asia (CA) and influencing the hydrological characteristics of river basins, flood risks, and water resource management. The goal of this systematic review is to synthesize the current knowledge on hydrological extremes and flood-related hazards in CA under changing hydro-climatic conditions, including an understanding of the dominant hydro-climatic processes, regional variability, methodological approaches, quality of the evidence, and implications for climate adaptation in CA. A PRISMA-guided systematic review and structured evidence appraisal framework were used to identify studies for this review from January 2021 to December 2025, published in peer-reviewed journals. A total of approximately 600 studies were found, and 42 studies were selected for inclusion in the final synthesis. Rather than a single factor causing flood-related hazards throughout CA, the review shows that hydro-climatic processes interact and contribute to these hazards. Extreme precipitation, alterations in the timing and amount of snowmelt, transitions between snow and rain, rain-on-snow processes, seasonal redistribution of runoff, and upstream–downstream human-climatic interactions are the most prominent drivers. The evidence also suggests significant regional variations in hydrological response, depending on the physiographic setting, hydro-climatic conditions, and availability of evidence. Despite recent advances in our understanding of climate-induced hydrological change, there are significant knowledge gaps in integrated multi-driver evaluations, mountain observations, transboundary synthesis, and the process of moving from science to decision-ready flood risk information. This review not only summarizes the current state of the science but also offers a structured evidence-based approach to assessing the scientific strength and regional representativeness of existing literature, as well as directions for future research. These findings provide comprehensive evidence to guide future research, flood risk assessment, and climate adaptation in CA, especially for national water authorities, river basin managers, infrastructure planners, and policymakers working on disaster risk reduction and climate adaptation.