Can flood paths be identified in mountainous areas? What is the solution? And what solutions can be offered to prevent flooding in human settlements in cities and villages?

like incessant rain, increased hydrostatic pressure, and rapid ice melt, a large amount of lake water can be suddenly released. This leads to dam instability and eventual breach, triggering a GLOF (number . Similarly, LLOFs also involve breaching dams. However, LLOFs dams are formed by earthquakes or rainfall-induced landslides blocking streams and rivers. The landslide carries soil, debris, and other materials blocking streams and rivers to form landslide dams .which in turn create dammed lakes. Rising lake levels and erosion of the dam’s sidewall can destabilize its structural integrity. If the dam fails, it can suddenly release large volumes of water downstream, triggering an LLOF (number .Overall, climate conditions interact with cryospheric and geological environments, collectively driving the occurrence and development of GLOFs and LLOFs. Y. Bai et al. Science Bulletin Our analysis shows that humans and infrastructure in HMA have been exposed to increased risk from various floods in the past seven decades. PFs have the broadest impact, causing at least 23,900 deaths and displacing 105 million people from 1950 to 2023. The PFs triggered by monsoon rains are particularly concerning due to their widespread impact, prolonged duration, and tendency to cause severe casualties and displacements (Fig. S11 online). Additionally, our statistical analysis reveals a significant positive correlation between the number of fatalities and rainfall intensity . Unlike PFs, SFs often mobilize large ice blocks and meltwater, potentially transforming or cascading into debris flows and landslides. On average, each SF in HMA has caused 18 fatalities, affected approximately 128,000 people, damaged 3,378 ha of crops and killed 553 livestock . GLOFs on the other hand have far-reaching impacts, also causing devastating damage to settlements and infrastructure downstream. For instance, over 6,000 fatalities were reported in June 2013 due to the Chorabari glacial lake outburst in the western Himalayas . Like GLOFs, when LLOFs occur, they release a huge volume of water, generating extremely high peak flows and catastrophic floods. Meanwhile, we observe a marked population growth and expansion of infrastructure (e.g., hydropower, buildings, and transportation) in HMA (Fig. S13 online), with an average annual growth rate of 1.53% and 7.11%, respectively. This growth trend is expected to continue under various socio-economic development scenarios .and the exposure to flood risks may further intensify in the future. Besides their direct impact on population and infrastructure, floods can trigger a series of environmental issues and landscape instabilities . Very extreme floods can transport large amounts of sediment and pollutants which could accumulate in downstream river channels and floodplains. These pose serious threats to human health and environmental safety and even delay postflood recovery efforts. For instance, in 1975, spring SFs in Xinjiang, China, washed a large amount of sediment into channels, resulting in 70,000 m3 of sediment accumulation and delaying channel discharge for several months (Fid16 in Table S2 online). Extreme floods can also alter river morphology, resulting in riverbed elevation changes, channel widening, or even river avulsion . For instance, such processes were observed when the Kosi River was flooding in 2008. . Additionally, floods may transport long buried soil organic carbon .and mercury, affecting the regional carbon cycle and drinking water quality. Our state-of-the-art flood inventory is comprehensively compiled from public databases, flood yearbooks, media reports, and literature, and highlights the changes of flood complexity over the past seven decades. We highlight the flood complexity and increasing flood exposure risks due to the growth of infrastructure and population in HMA. The complex trends in flooding frequency arise from the interplay between climate warming, shifted precipitation patterns, rapid melting of glaciers, snow cover, and permafrost, as well as more research and public attention (Supplementary Text S6 online). In a warming future accompanied by accelerating glacier melting, snowfall-rainfall shift, more frequent rainfall extremes, and growing human activities, flooding risk in HMA is expected to further increase without effective adaptive measures. We emphasize that identifying risk-sensitive areas and adjusting the spatial distribution of population and socio-economic activities are essential in the future. Additionally, international data sharing and encouraging indigenous people, especially the youth, to participate in local flood mitigation efforts are vital for creating further awareness and addressing climate challenges in HMA.