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The Jordan River Basin is experiencing significant water security stress, primarily due to increases in population and agricultural demands. The complex geopolitical dynamics of the region pose challenges in collecting field data such as precipitation and evapotranspiration. Consequently, remote sensing data have emerged as indispensable tools for assessing water availability in the basin. The objective of this research study is to utilize data compiled from the water years of 2003 to 2021 to evaluate water availability in the basin. The water flux data, derived from satellite-observed precipitation (Climate Hazards Group InfraRed Precipitation with Station data, CHIRPS) and evapotranspiration (Simplified Surface Energy Balance, SSEBop), offer a comprehensive summary of hydrologic information for each land use class and country. The annual land use maps were acquired from the European Space Agency Climate Change Initiative (ESA CCI). Results indicate an overall rise in evapotranspiration (3.2%) in the basin between the periods of 2003–2011 and 2012–2020. Increased water consumption, particularly in croplands and urban areas (42%), poses a significant future challenge. These findings can guide the development of effective water resource management policies to enhance water security in a region that is vulnerable to the impacts of climate change.

Glacial retreat causes the formation of glacier lakes with the potential of producing glacial lake outburst floods (GLOFs). Imja Lake in Nepal is considered at risk for a GLOF. Communities in the path of a potential Imja GLOF are implementing adaptation projects, yet no quantitative data or guidance is available to understand the benefits of these projects or how to weigh benefits against the cost of implementation. We develop and demonstrate a decision-making methodology for GLOF risk management, incorporating available scientific information and uncertainty. The methodology consists of (1) identifying flooding scenarios, (2) evaluating scenario consequences, and (3) performing an economic analysis of proposed adaptation projects. The methodology is applied to assess benefits in Dingboche of lowering Imja Lake by 3, 10 and 20 m. The results show that the baseline case (no lake lowering) has the lowest expected cost because of low valuation of agricultural land and homes in the literature. Nonetheless, the result is sensitive to changes in the analysis variables. We also found that lowering the lake by 10 or 20 m is efficient according only to the methodology used here; however, considering only direct economic damages and literature cost estimates, the costs outweigh the benefits for these projects.

Glacial lakes in the Nepal Himalaya can threaten downstream communities and have large socio-economic consequences if an outburst flood occurs. This study identified 131 glacial lakes in Nepal in 2015 that are greater than 0.1 km2 and performed a first-pass hazard and risk assessment for each lake. The hazard assessment included mass entering the lake, the moraine stability, and how lake expansion will alter the lake’s hazard in the next 15–30 years. A geometric flood model was used to quantify potential hydropower systems, buildings, agricultural land, and bridges that could be affected by a glacial lake outburst flood. The hazard and downstream impacts were combined to classify the risk associated with each lake. 11 lakes were classified as very high risk and 31 as high risk. The potential flood volume was also estimated and used to prioritize the glacial lakes that are the highest risk, which included Phoksundo Tal, Tsho Rolpa, Chamlang North Tsho, Chamlang South Tsho, and Lumding Tsho. These results are intended to assist stakeholders and decision makers in making well-informed decisions with respect to the glacial lakes that should be the focus of future field studies, modeling efforts, and risk-mitigation actions.