Severe Water Scarcity Research Articles

Modeling water availability under climate change scenarios: a systemic approach in the metropolitan area in Morelos, México

The research investigates integrated water management with complex socio-environmental interactions in worsening climate change scenarios. The proposed methodology involves the integration of Atmosphere–Ocean General Circulation Models (AOGCM) with Water Evaluation and Planning models (WEAP) to ensure water availability in the future. Two Shared Socioeconomic Pathways (SSP) integrate environmental, socioeconomic, and political elements under climate change scenarios with greater rainfall variability, extreme droughts, and floods in the metropolitan area of Morelos, located in the Center of México. Water availability in this region, along with population growth, industrialization, service activities, and agriculture, depends on forest conservation in the Ravines System of Northwest Morelos (RSNM). Public policy lacks interdisciplinary socio-environmental development, which prioritizes unsustainable economic growth overexploiting aquifers and polluting rivers. Official data from national and state governments do not reflect water conditions, and aquifer statistics date back decades. The majority of the analyzed models predict a delay in the monsoon, higher temperatures, extreme climate events, depletion of groundwater, and severe water scarcity during the hot months, rendering them unable to meet the increasing demand. This research provides valuable insights into the complex socioeconomic dynamics of a region with future water scarcity, which could be useful for similar conditions in the Global South.

Water Volume and 3D Topographic Analysis of Hub Dam, Karachi, Using Remote Sensing and Global Bathymetry Data

Background: Karachi one of the largest and fastest-growing cities in the world, the city faces severe water scarcity and aggravated by climate change, excessive groundwater extraction in dense urban areas and inefficient water distribution systems. The Hub Dam, along with the Keenjhar Lake, is the source of water for Karachi's population as well as for the industrial and urban agricultural sectors. It is therefore important to have current information on the dam's storage capacity, its topographic features and the hydrological dynamics of its catchment area, which remains poorly understood to date. Objectives: This study's primary objectives are (1) to assess the hydrography of Hub Dam using global bathymetric and remote sensing data and (2) to create a detailed 3D model of the dam to facilitate analysis of its hydrological features. (3) Also generate data-driven insights to guide improvements in Karachi’s urban water management policies. Methods: The methodology integrates global bathymetric data with remote sensing and Google Earth Engine (GEE) for analysing Hub Dam’s hydrological and topographic characteristics. Data processing and visualization were conducted in Google Colab by python codes. This process enabling an efficient workflow for handling and analysing large datasets. Results: Hub Dam 3D model is developed. The approaches is enhancing visualization of the dam's water volume and terrain features to support detailed hydrological analysis. 3D volumetric analysis estimates with total water volume at approximately 79.954 · 106 m3. It was found that currently, the Hub Dam reservoir has enough water to fulfil Karachi needs for 503 days, a critical reserve for urban planning, resource management. Using a topographic analysis that includes surrounding slopes and watershed features, key elements affecting dam performance were identified. This result helps to adjust the filling of the dam with water. The Hub Dam's ability to store water was confirmed through a preliminary volume assessment. Conclusion: The study successfully achieved its objectives. The results obtained highlight the importance of adaptive well informed strategies for sustaining well managed water resources in response to environmental pressures. The current study further advance rational water management by integrating remote sensing and data-driven methodologies into this area of knowledge. That is, the effectiveness of Using Remote Sensing and Global Bathymetry Data has been repeatedly proven by other studies in different areas of knowledge. However, in the current study, this scientific approach has successfully demonstrated the efficient and rapid acquisition of accurate, up-to-date information on reservoir capacity and hydrological characteristics, which opens up new opportunities for efficient water management.

Potential Sites for Rainwater Harvesting Focusing on the Sustainable Development Goals Using Remote Sensing and Geographical Information System

An innovative way to combat water scarcity brought on by population increase and climate change is rainwater harvesting (RWH), particularly in arid and semiarid areas. Currently, Pakistan is facing major water issues due to underprivileged water resource management, climate change, land use changes, and the sustainability of local water resources. This research aims to find out the suitable sites and options for RWH structures in the Quetta district of Pakistan by integrating the depression depth technique, Boolean analysis, and weighted linear combination (WLC) with hydrological modeling (HM), multicriteria analysis (MCA), a geographic information system (GIS), and remote sensing (RS). To find suitable sites for RWH, a collection of twelve (12) thematic layers were used, including the slope (SL), land use land cover (LULC), subarea (SA), runoff depth (RD), drainage density (DD), lineament density (LD), infiltration number (IFN), distance from built-up area (DB), distance from roads (DR), distance from lakes (DL), maximum flow distance (MFD), and topographic wetness index (TWI). The Boolean analysis and WLC approach were integrated in the GIS environment. The consistency ratio (CR) was calculated to make sure the assigned weights to thematic layers were consistent. Overall, results show that 6.36% (167.418 km2), 14.34% (377.284 km2), 16.36% (430.444 km2), 18.92% (497.663 km2), and 18.64% (490.224 km2) of the area are in the categories of very high, high, moderate, low, and very low suitability, respectively, for RWH. RWH potential is restricted to 25.35% (666.86 km2) of the area. This research also identifies the five (5) best locations for checking dams and the ten (10) best locations for percolation tanks on the streams. The conducted suitability analysis will assist stakeholders in selecting the optimal locations for RWH structures, facilitating the storage of water, and addressing the severe water scarcity prevalent in the area. This study proposes a novel approach to handle the problems of water shortage in conjunction with environmental and socioeconomic pressures in order to achieve the sustainable development goals (SDGs).

Challenges of restoring streams to a free-flowing state in semi-arid Mediterranean areas: Lotic systems in Cyprus from the perspective of the Water Framework Directive

Hydromorphological alterations are the most common pressures that occur in freshwater ecosystems, largely responsible for the overall decline of freshwater biodiversity. The EU 2030 Biodiversity Strategy, recognizing the crucial role of hydromorphological alterations, sets the target of 25 000 km of free flowing rivers in Europe by 2030. In this article, we discuss the hydromorphological restoration and mitigation measures in stream ecosystems implemented in Cyprus, the most arid country in the EU. We also assess their ability to contribute to the accomplishment of a free-flowing state, and we highlight the need for restoration guidelines for semi-arid areas in light of the climate crisis and the anticipated changes in water flow regimes. Our study showed that important progress has been made towards reconnecting streams in Cyprus, with the Water Framework Directive (WFD) being the main driving force behind this effort. However, even in semi-arid areas with severe water scarcity, emphasis should be placed on the demolition of dams and other water storage obstructions, as they are primarily responsible for the interruption of stream continuity. Thus, the development of a prioritization tool is required. Although we focus on the hydromorphological restorations in Mediterranean streams, we argue that the issues raised in this paper concern other geographical regions and river types with similar flow regimes and future challenges.

Remote Sensing-Based Drought Monitoring in Iran’s Sistan and Balouchestan Province

Drought is a natural phenomenon that has adverse effects on agriculture, the economy, and human well-being. The primary objective of this research was to comprehensively understand the drought conditions in Sistan and Balouchestan Province from 2002 to 2017 from two perspectives: vegetation cover and hydrology. To achieve this goal, the study utilized MODIS satellite data in the first part to monitor vegetation cover as an indicator of agricultural drought. In the second part, GRACE satellite data were employed to analyze changes in groundwater resources as an indicator of hydrological drought. To assess vegetation drought, four indices were used: Vegetation Health Index (VHI), Vegetation Drought Index (VDI), Visible Infrared Drought Index (VSDI), and Temperature Vegetation Drought Index (TVDI). To validate vegetation drought indices, they were compared with Global Land Data Assimilation System (GLDAS) precipitation data. The vegetation indices showed a strong, statistically significant correlation with GLDAS precipitation data in most regions of the province. Among all indices, the VHI showed the highest correlation with precipitation (moderate (0.3–0.7) in 51.7% and strong (≥0.7) in 45.82% of lands). The output of vegetation indices revealed that the study province has experienced widespread drought in recent years. The results showed that the southern and central regions of the province have faced more severe drought classes. In the second part of this research, hydrological drought monitoring was conducted in fifty third-order sub-basins located within the study province using the Total Water Storage (TWS) deficit, Drought Severity, and Total Storage Deficit Index (TSDI Index). Annual average calculations of the TWS deficit over the period from April 2012 to 2016 indicated a substantial depletion of groundwater reserves in the province, amounting to a cumulative loss of 12.2 km3 Analysis results indicate that drought severity continuously increased in all study basins until the end of the study period. Studies have shown that all the studied basins are facing severe and prolonged water scarcity. Among the 50 studied basins, the Rahmatabad basin, located in the semi-arid northern regions of the province, has experienced the most severe drought. This basin has experienced five drought events, particularly one lasting 89 consecutive months and causing a reduction of more than 665.99 km3. of water in month 1, placing it in a critical condition. On the other hand, the Niskoofan Chabahar basin, located in the tropical southern part of the province near the Sea of Oman, has experienced the lowest reduction in water volume with 10 drought events and a decrease of approximately 111.214 km3. in month 1. However, even this basin has not been spared from prolonged droughts. Analysis of drought index graphs across different severity classes confirmed that all watersheds experienced drought conditions, particularly in the later years of this period. Data analysis revealed a severe water crisis in the province. Urgent and coordinated actions are needed to address this challenge. Transitioning to drought-resistant crops, enhancing irrigation efficiency, and securing water rights are essential steps towards a sustainable future.

Modelling scenarios for water supply and sanitation technologies in Jordan

The influx of refugees, population growth and current agricultural practices have led to an increase in water demand in Jordan, placing pressure on existing water provision. Climate change further exacerbates declining water availability. Against this backdrop, the techno-economic feasibility of four water supply and sanitation alternatives for small and medium scale cities in Jordan were explored, using local unit costs and Al-Mafraq as a case study. City level piped network combined with household rooftop rainwater harvesting and surface runoff collection into local ponds and piped networks with treatment using the nature-based solution of root-zone for sanitation were demonstrated to provide the highest benefits in terms of cost, convenience and water conservation. Our work highlights the need to invest in long-term urban infrastructure networks to promote sustainable future growth of cities. This is vital to address severe water scarcity challenges that ultimately impact those at the urban fringes most.

Investigating the impacts of different degrees of deficit irrigation and nitrogen interactions on assimilate translocation, yield, and resource use efficiencies in winter wheat

Water and nitrogen (N) are recognized as the primary determinants influencing the development and output of winter wheat. They affect the growth of winter wheat not only through their own changes, but also through their interaction. The translocation and accumulation of pre- and post-anthesis assimilates (including dry matter and N) are important physiological processes in winter wheat, which are closely related to the resource use efficiency and yield. However, a dearth of research exists that examines the complex interplay between varying water levels, especially severe water deficit, and N deficiency levels on the growth dynamics of winter wheat. The purpose of this study was to quantify and compare the effects of different degrees of water deficit and N interaction on assimilate translocation, water and N use efficiency and yield of winter wheat. A four-year long-term field experiment conducted under the rain-out shelter including four irrigation and two N levels was launched during 2019–2023. This method avoided the impact of precipitation on water treatment and helped to achieve serious water deficit treatment. The findings indicated that the higher N application improved the wheat's ability by 49.6 % - 362.3 % to utilize the available soil water. The pre- and post-anthesis translocation and accumulation of assimilates (including dry matter and N) in winter wheat increase alongside elevated levels of water and N application, except under severe water deficit treatment. Plants under mild to moderate water deficit were better able to translocate the pre-anthesis assimilates. However, the severe water deficit hindered the re-translocation of assimilates before anthesis. Providing additional N during periods of severe water scarcity leads to a 13.4 % - 44.7 % reduction in water use efficiency (WUE). Furthermore, both the irrigation water use efficiency and WUE diminished by 10.3 % - 60.5 % and 4.5 % - 41.4 % with higher levels of irrigation, while improved by 24.4 % - 48.2 % and 12.6 % - 39.4 % with higher N application rates. Conversely, N partial factor productivity and N use efficiency followed the opposite trend. Similar to WUE, increasing N application under severe water deficit would result in a yield reduction of 38.7 %. The reduction in crop yield resulting from severe water stress was primarily ascribed to the decline in the kernels number per spike (up to 74.9 %), with the reduction in spike number per unit area following closely behind (up to 29.1 %). This integrated approach, combining resource use efficiency with a detailed assessment of assimilate dynamics, provides a holistic view of how water and N management strategies impact winter wheat performance. The findings will offer precise insights for developing targeted irrigation and N scheduling strategies for sustaining both winter wheat production and environmental sustainability.

Detección de roca intrusiva alterada mediante tomografía de resistividad eléctrica: El caso del área de San Luis, zona central de Panamá

This work investigates the potentiality of the 2D electrical resistivity tomography method to delineate an altered intrusive rock domain. The detection and characterization of such altered domains are crucial to understanding local hydrogeological conditions. Here, the target is the San Luis area, located in the northern part of the Estibaná River watershed, within the Los Santos Province in the central region of the Isthmus of Panama. First, a detailed geological survey was carried out to better constrain the tectonic structures. Then, two geological sections were developed based on two 2D electrical resistivity tomographies. A geoelectrical simulation process was conducted in both sections to set theoretical models whose model responses (synthetic field data set) would be consistent with the observations. After appropriate selection of the inversion parameters by using the Boundless Electrical Resistivity Tomography (BERT) code, the observations were processed, resulting in low calculation errors (2 < 0.51). Based on the superficial geological information and the results of the geophysical modelling, two profiles were established, depicting the lateral and in-depth distribution of rocks and sediments. The limit of the Ocú-Parita fault zone was identified as well. The results of the 2D inversion of the synthetic data, obtained with the established theoretical models, are consistent with the 2D inversion of the observations. Electrical resistivity tomography studies can be useful in establishing groundwater management models, particularly in areas that experience severe water scarcity during the dry season.

Evaluation of water resource balance in the Urmia Lake Basin: Integrating carrying capacity and water footprint model for sustainable management

Given the scarcity of water resources and the ever-growing demand, effective water flow management becomes crucial. The Lake Urmia Basin, a critical region in Iran, faces severe water scarcity exacerbated by climatic changes, land use alterations, over-extraction of groundwater, and mismanagement. This study evaluates the water resource balance by integrating carrying capacity and water footprint models to assess sustainable water management practices. Utilizing the InVEST model, water provisioning ecosystem services have been estimated as the supply, while the ecological footprint method quantifies water demand across various sectors. Three scenarios are evaluated: continuation of the current situation, an ideal scenario with substantial reductions in water consumption and pollution, and implementation of operational programs. The findings reveal significant water deficits in certain sub-basins, highlighting the need for a fundamental revision of resource allocation based on each region’s ecological capacity. Lake Urmia, the central nucleus of the basin, has experienced a significant size reduction, approximately 10 % of its original size, from the early 1990s to 2018, due to climatic changes, land use alterations, over-extraction of groundwater, and mismanagement. The environmental deficit in some sub-basins raises serious concerns, even in the best scenario where ecological footprint reduction is considered. These results underscore the effectiveness of ecosystem-based comprehensive capacity analysis for sustainable watershed development. This research offers a unified spatial system for quantifying ecological footprints and land resilience, providing critical insights into addressing water scarcity and supporting holistic regional planning.

Population genetic diversity and environmental adaptation of Tamarix hispida in the Tarim Basin, arid Northwestern China.

Arid ecosystems, characterized by severe water scarcity, play a crucial role in preserving Earth's biodiversity and resources. The Tarim Basin in Northwestern China, a typical arid region isolated by the Tianshan Mountains and expansive deserts, provides a special study area for investigating how plant response and adaptation to such environments. Tamarix hispida, a species well adapted to saline-alkaline and drought conditions, dominates in the saline-alkali lands of the Tarim Basin. This study aims to examine the genetic diversity and environmental adaptation of T. hispida in the Tarim Basin. Genomic SNPs for a total of 160 individuals from 17 populations were generated using dd-RAD sequencing approach. Population genetic structure and genetic diversity were analyzed by methods including ADMIXTURE, PCA, and phylogenetic tree. Environmental association analysis (EAA) was performed using LFMM and RDA analyses. The results revealed two major genetic lineages with geographical substitution patterns from west to east, indicating significant gene flow and hybridization. Environmental factors such as Precipitation Seasonality (bio15) and Topsoil Sand Fraction (T_SAND) significantly shaped allele frequencies, supporting the species' genetic adaptability. Several genes associated with environmental adaptation were identified and annotated, highlighting physiological and metabolic processes crucial for survival in arid conditions. The study highlights the role of geographical isolation and environmental factors in shaping genetic structure and adaptive evolution. The identified adaptive genes related to stress tolerance emphasize the species' resilience and highlight the importance of specific physiological and metabolic pathways.

Climate change, conflict, and urban migration

The adverse effects of man-made climate change and protracted conflict intensify rural-to-urban migration in many developing countries. This article examines the impacts of climate and conflict migration on urban environments and on migrants themselves. To trace the distinctive pathways by which climate change and conflict drive migration as well as shared challenges for urban planning and services, we employ qualitative case studies of Jordan, Pakistan, and Honduras informed by interviews and secondary literature. These countries are chosen as they exemplify the compounding, cumulative impacts of climate change and conflict on urban expansion and the challenges in providing adequate public services in these contexts. Across all three cases, climate hazards threaten rural livelihoods and agricultural productivity, increasing rural to urban migration, while civil conflict and gang violence further induce urban migration, both internally and across borders. In Jordan, we assess the impacts of increasing water scarcity and conflict-driven refugee flows on infrastructure and public services. Pakistan’s experience highlights the impacts of rapid-onset natural disasters, severe water scarcity, and enduring refugee flows from Afghanistan on environmental quality and pollution within cities. In Honduras, we analyze how increasing droughts and hurricanes, combined with gang presence in cities, affect migrants in terms of increased violence and negative physical and mental health impacts. Together, these cases illuminate the need for context-specific proactive policy measures that address the independent and interrelated ways that climate change and conflict lead to migration and the subsequent profound impacts on urban development and human well-being.

Effect of Droplet-Removal Processes on Fog-Harvesting Performance on Wettability-Controlled Wire Array with Staggered Arrangement.

Development of freshwater resources is vital to overcoming severe worldwide water scarcity. Fog harvesting has attracted attention as a candidate technology that can be used to obtain fresh water from a stream of foggy air without energy input. Drainage of captured droplets from fog harvesters is necessary to maintain the permeability of harp-shaped harvesters. In the present study, we investigated the effect of the droplet-removal process on the amount of water harvested using a harvester constructed by wettability-controlled wires with an alternating and staggered arrangement. Droplet transfer from hydrophobic to hydrophilic wires, located upstream and downstream of the fog flow, respectively, was observed with a fog velocity greater than 1.5 m/s. The proportion of harvesting resulting from droplet transfer exceeded 30% of the total, and it reflected more than 20% increase of the harvesting performance compared with that of a harvester with wires of the same wettability: this value varied with the adhesive property of the wires and fog velocity. Scaled-up and multilayered harvesters were developed to enhance harvesting performance. We demonstrated certain enhancements under multilayered conditions and obtained 15.99 g/30 min as the maximum harvested amount, which corresponds to 13.3% of the liquid contained in the fog stream and is enhanced by 10% compared with that without droplet transfer.

Island Water Management Cyprus Facts Finding Mission and Gap Identifications

Water management on islands faces unique challenges due to limited size, isolation, climate change impacts, and economic development needs. These factors intensify water scarcity, highlighting the need for sustainable resource development through multidisciplinary approaches. Cyprus, the third-largest Mediterranean island, exemplifies these challenges, with the lowest water availability per capita in the region and severe water scarcity exacerbated by climate change. Addressing these issues requires a comprehensive master plan that integrates technical, environmental, social, and economic factors, focusing on climate change impacts on the water cycle. The Energy, Environment, and Water Research Center (EEWRC) plays a pivotal role in global resource management, emphasizing sustainable development goals and Integrated Water Resources Management Policy. EEWRC’s key initiatives include hydrodiplomacy and WEF Nexus and Integrated Water Resource Management IWRM, monitoring sediment transport pollution, water quality monitoring of basins and aquifers, smart water management of conventional and non-conventional water, and nature-based solutions for water and land management integration. To improve water management in Cyprus, establishing a National Commission for Water Experts is recommended. This commission would provide a detailed roadmap for water management, aligning with Sustainable Development Goals (SDGs) and the Climate Change Initiative coordinated by the Cyprus Institute. Additionally, organizing a conference focused on “Cyprus Island Water Management” would help launch this concept. In conclusion, it is crucial to develop a long-term strategy for optimal water resource management in Cyprus, addressing water issues, promoting conservation, launching climate-resilient initiatives, and fostering collaboration with national and international entities for success.

Exploring household water conservation methods in rural South Africa: a case of the Mbhashe and Mnquma local municipalities

Amidst the persistent drought disaster declared in 2015, the Amathole District Municipality grapples with severe water scarcity issues, particularly affecting local municipalities such as Mbhashe and Mnquma. Consequently, households in these areas confront the challenges of unreliable and contaminated water sources, prompting them to adopt water conservation measures to mitigate shortages. This study investigates the efficacy of water conservation methods among rural households in these drought-affected regions. It identifies associated challenges and potential interventions to ensure access to clean and dependable water. Employing a mixed methods approach, the study examines household water conservation practices through narrative analysis and descriptive statistics of survey data. Findings reveal that storing water in drums, containers, and tanks is the most prevalent conservation method, alongside measures like greywater reuse, lifestyle adjustments, and rainwater harvesting. With financial constraints and infrastructural limitations hindering broader adoption, the study found water conservation to be a challenge among the households as a minority (7.8%) of respondents adopted multiple water conservation strategies. In comparison, most respondents (73.6%) could only afford to practice one water conservation strategy at a time, and others (18.6%) had no conservation strategies. Drought conditions, lack of infrastructure, poverty, and attitudinal factors are primary barriers to effective water conservation. The study underscores the need for municipal-level initiatives to enhance water sources and advocates for increased investment in education, awareness campaigns, and policy interventions to address rural communities’ water scarcity challenges.

Between a rock and a hard place: A geosocial approach to water insecurity in Kabul

Approximately 50% of the global population currently experiences severe water scarcity, a situation likely to intensify due to climate change. At the same time, the poorest population segments bear the greatest burden of water insecurity. This intersection of geophysical, geochemical, and socio-economic dimensions of water (in)security challenges requires a geosocial perspective, one that attends simultaneously to geophysical, geochemical, and socio-economic dimensions. Our qualitative study, conducted through 68 semi-structured interviews across two distinct sub-basins in Kabul, revealed disparities in groundwater levels, water quality, water prices, and lived experiences of water insecurity. While environmental stressors like drought and groundwater contamination contribute to water insecurity, socio-economic factors such as gender and property ownership exacerbate these impacts: Women and children bear a heavy burden of securing water, with children’s involvement in water-fetching leading to instances of violence. Furthermore, trucked water costs 33 times that of piped water, echoing alarming global trends where less privileged communities endure disproportionately greater challenges of water inaccessibility. We outline policy implications for monitoring groundwater abstraction and underscore the need for tailored strategies to combat water scarcity, such as pro-poor water strategies. Additionally, our work draws attention to the role of local gatekeepers who have informally regulated water usage in response to drought-induced scarcity, particularly in the absence of functioning government policies, underscoring the importance of collaboration with local stakeholders to ensure sustainable access to water. We argue that a geosocial approach to water (in)security can provide high-resolution findings and reveal critical gaps between common metrics and the realities of water (in)security, which also underlines the need for integrated approaches incorporating both quantitative and qualitative research.

Untapped Potential of Groundwater Resources of Bihar

"Bihar is endowed with rich water resources due to the high precipitation, extensive river basin network, and alluvial aquifer with significant storage space for groundwater. Majority of its population is dependent on agriculture and related activities for their sustenance. However, there is uneven distribution of groundwater potentials due to variability of rainfall. Although evidence at the aggregate level indicates the under-utilization of groundwater resources in Bihar, there are few areas with depleting groundwater levels as well. This is indicated by the increase in the over-exploited and critical blocks from zero per cent to 1.5 and 2.2 per cent respectively. Irrigation being the predominant consumer of groundwater bears the prime responsibility of using this resource sustainably. Presently, groundwater irrigates 63% of the net irrigated area and its share has been rising. Various studies on water quality and quantity indicate that Bihar may experience severe scarcity of water in the nearby future. Water shortages will become chronic in this water surplus condition, necessitating quick remedial measures to conserve and protect this vital water supply. As groundwater is largely underutilized, there exists a huge scope to accelerate sustainable use of groundwater for harnessing a positive groundwater-agricultural development linkage. The untapped groundwater resource should be utilized by private and government agencies for irrigation."

Performance modeling and cost optimization of a solar desalination system using forward osmosis with energy storage

This study presents the design and performance evaluation of a solar-driven water desalination system based on forward osmosis (FO) with thermally responsive ionic liquids (ILs). FO is a two-step process involving dilution of the ILs with water, followed by heating above a critical temperature to induce phase separation of liquid water from the IL. This regeneration step can be achieved by integrating FO with low-grade solar energy, which is abundant in regions that face severe water scarcity. A system design is presented that couples an FO membrane module with a compound parabolic concentrator solar collector and thermal energy storage to minimize solar intermittency and produce clean water at a distributed scale of 10 m3/day. To determine the optimal sizing of components in the system, a technoeconomic analysis using the TRNSYS software is performed with the goal of minimizing the levelized cost of water (LCOW). Notably, over 96 % of the energy required for regeneration comes from solar energy and/or the thermal energy storage (TES) in all cases, with auxiliary heat from electricity being used to maintain a continuous process. To evaluate the potential of solar-FO in three different locations within the United States, a case study is presented for Phoenix, AZ; San Diego, CA; and Atlanta, GA. The simulation results reveal that for a small-scale desalination system, LCOW values as low as $1.31/m3 can be attained, with the potential to approach $1/m3 by lowering the costs of the solar collector and FO module based on a sensitivity analysis.

Climate-adaptive crop distribution can feed food demand, improve water scarcity, and reduce greenhouse gas emissions

Optimizing crop distribution stands as a pivotal approach to climate change adaption, enhancing crop production sustainability, and has been recognized for its immense potential in ensuring food security while minimizing environmental impacts. Here, we developed a climate-adaptive framework to optimize the distribution of staple crops (i.e., wheat, maize, and rice) to meet the multi-dimensional needs of crop production in China. The framework considers the feasibility of the multiple cropping systems (harvesting more than once on a cropland a year) and adopts a multi-dimensional approach, incorporating goals related to crop production, water consumption, and greenhouse gas (GHG) emissions. By optimizing, the total irrigated area of three crops would decrease by 7.7 % accompanied by a substantial 69.8 % increase in rain-fed areas compared to the baseline in 2010. This optimized strategy resulted in a notable 10.0 % reduction in total GHG emissions and a 13.1 % decrease in irrigation water consumption while maintaining consistent crop production levels. In 2030, maintaining the existing crop distribution and relying solely on yield growth would lead to a significant maize production shortfall of 27.0 %, highlighting a looming challenge. To address this concern, strategic adjustments were made by reducing irrigated areas for wheat, rice, and maize by 2.3 %, 12.8 %, and 6.1 %, respectively, while simultaneously augmenting rain-fed areas for wheat and maize by 120.2 % and 55.9 %, respectively. These modifications ensure that production demands for all three crops are met, while yielding a 6.9 % reduction in GHG emissions and a 15.1 % reduction in irrigation water consumption. This optimization strategy offers a promising solution to alleviate severe water scarcity issues and secure a sustainable agricultural future, effectively adapting to evolving crop production demands in China.

Water Scarcity Assessment of Hydropower Plants in China under Climate Change, Sectoral Competition, and Energy Expansion.

Hydropower plays a pivotal role in low-carbon electricity generation, yet many projects are situated in regions facing heightened water scarcity risks. This research devised a plant-level Hydropower Water Scarcity Index (HWSI), derived from the ratio of water demand for electricity generation to basin-scale available runoff water. We assessed the water scarcity of 1736 hydropower plants in China for the baseline year 2018 and projected into the future from 2025 to 2060. The results indicate a notable increase in hydropower generation facing moderate to severe water scarcity (HWSI >0.05), rising from 10% in 2018 to 24-34% of the national total (430-630 TWh), with a projected peak in the 2030s-2040s under the most pessimistic scenarios. Hotspots of risk are situated in the southwest and northern regions, primarily driven by decreased river basin runoff and intensified sectoral water use, rather than by hydropower demand expansion. Comparative analysis of four adaptation strategies revealed that sectoral water savings and enhancing power generation efficiency are the most effective, potentially mitigating a high of 16% of hydropower risks in China. This study provides insights for formulating region-specific adaptation strategies and assessing energy-water security in the face of evolving environmental and societal challenges.

Economic significance and environmental impacts of the Song Dam Drinking Water Project (SDDWP) in Garhwal Himalaya

With the population growth through natural growth and migration, coupled with the city expansion, it is the fact that Dehradun City in India faces severe water scarcity. Therefore, the Song Dam Drinking Water Project (SDDWP) is proposed to provide ample drinking water to Dehradun City and its suburban areas. This paper examined economic significance and environmental impacts of the SDDWP in Garhwal Himalaya, India. To conduct this study, we collected data from both primary and secondary sources. There are 12 villages and 3 forest divisions in the surrounding areas of the proposed dam project, of which 3 villages will be fully submerged and 50 households will be affected. For this study, 50 heads of the households were interviewed in the 3 submerged villages. The questions mainly focused on economic significance, environmental impacts, and rehabilitation issues of the dam project. The findings of this study indicate that economic significance of the dam project is substantial, including providing ample water for drinking and irrigation, contributing to groundwater recharge, creating job opportunities, and promoting the development of tourism and fisheries in the Doon Valley. In terms of the rehabilitation of the affected people, there are only 50 households in need of rehabilitation. Currently, the arable land of these affected people is not sufficient to sustain their livelihoods. The entire landscape is fragile, rugged, and precipitous; therefore, the affected people are willing to rehabilitate to more suitable areas in the Doon Valley. Moreover, it is essential to provide them with sufficient compensation packages including the compensation of arable land, houses, cash, common property resources, institutions, belongingness, and cultural adaptation. On the other hand, the proposed dam project will have adverse environmental impacts including arable land degradation, forest degradation, loss of fauna and flora, soil erosion, landslides, and soil siltation. These impacts will lead to the ecological imbalances in both upstream and downstream areas. This study suggests that the affected people should be given sufficient compensation packages in all respects. Afforestation programs can be launched in the degraded areas to compensate for the loss of forest in the affected areas.