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• Paper explores the local state, a framework to connect analyses of state, market and civil society in communities below the national level. • The local state concept is employed here to assess climate change adaptation (CCA), focusing on a case study of water resources in Tucson, AZ. • The Tucson case examines rainwater harvesting and the role of the water industry, local government organizations and civil society groups. • Barriers to CCA can be explained in the context of pre-existing policies and the complex dynamics of the local state. As climate change becomes a more obvious existential threat to many communities, sharper tools are needed to analyze policymaking and especially the variations in effective adaptive planning. While policy creation, preparedness and disaster management are essentially local activities, much analysis simply focuses on cities and overlooks robust tools to understand what happens within communities of all types. This paper explores the local state, an analytical framework which can connect our understanding of state, market and civil society within communities below the level of the nation state. The local state concept is resurgent within the academic literature and this paper shows the potential of this analysis, drawing on empirical examples of climate change adaptation from Tucson AZ and New Orleans, coupled with broader discussion from several countries. [ABSTRACT FROM AUTHOR]

The ability of Bayesian networks (BNs) to model complex systems and uncertainties makes it a perfect tool for the research on subfields related to climate change. In fact, in the past 30 years, BNs have been widely used in this field, with 1502 articles in total. Quantitatively understanding influential researchers, institutions, mainstream topics and research trends will help us quickly go deeper into this field. Thus, a scientometric method was conducted. In this paper, we identified the influential authors, journals, countries, institutions, topics and disciplines, key articles and research trends by collaboration network analysis, keyword co-occurrence network and document co-citation network analysis. As a result, we found that environmental sciences technology and water resources were the most popular research subfields, followed by energy fuels and meteorological atmospheric sciences. While as time goes on, research focuses have gradually shifted. Public environmental occupational health will become one of the most popular research subfields in the future. • We review papers of Bayesian networks in the subfields of climate change. • Influential journals, institutions, landmark papers, citation bursts are identified. • Recent topics focus on environmental sciences technology. • Public environmental occupational health will become new hot issues. [ABSTRACT FROM AUTHOR]

This paper reports on a study of the determinants of adaptive behavior in face of climate-driven water insecurity, using a survey of 400 urban dwellers in Lima, Peru. Lima is characterized by continuous water stress and is at risk of permanent water scarcity due to climate change. Residents show a general understanding that the climate is changing and have recent experience with climate extremes. We use regression analyses to identify the socioeconomic, socio-institutional, and psychological determinants of adaptive behavior. We examine the differences between climate-responsive and general adaptive behavior, using five indices -- structural, knowledge, consumption, planning, and environmental -- to identify and compare the determinants of both behaviors. Our findings show that education, extended water availability, climate change concern, and cultural environmental values influence adaptive behavior, and each thematic index has distinct set of significant behavioral determinants. We discuss the importance of water-related determinants, the intentionality of adaption behavior, and the need to contextualize the social and psychological realities of urban dwellers in the Global South. • Education, extended water availability, climate change concern, and cultural environmental values influence adaptive behavior. • The climate-responsive and general adaptive behavior determinants that differ are related to self-transcendence values. • Water-specific urban processes prove significant to explain adaptive behavior. • Individuals' social distance to climate change does not prevent them from adapting to climate change. • The assumption that social trust is a condition for adaptation is contested. [ABSTRACT FROM AUTHOR]

• A novel approach is proposed for evaluating future intra-basin water resources. • Under the SSP2–4.5 scenario, the MRBM is projected to face water scarcity by 2050. • Population and land use imbalance upstream/downstream reduce the PWR by 37 % and 69 %. • Precipitation, ET, population, agricultural land, and PWR increase downstream. • The upstream areas are expected to have greater PWR per capita and agriculture area. The Major River Basins in Madagascar (MRBM) play a crucial role in providing water to the Malagasy population as well as the ecosystem. Little is known about the impact of climate change on these basins, and it is not clear what factors have the most significant impact on them. There are two central objectives of this study: 1. To assess the future potential water available for daily life and agriculture use across the MRBM. 2. To compare the projected change within the MRBM with the historical trends analysis and identify the water-stressed basins. In this paper, a new method for assessing the future available Intra-basin water resources combined with the impacts of climate change, land use, and population is proposed. Three imbalance indicators are introduced to quantify the spatial availability (indicator N°1), distribution (indicator N°2), and variability (indicator N°3) of the Potential Water Resources (PWR) available and have been applied to the MRBM. Under the SSP2–4.5 scenario, results showed a decreasing trend of the PWR in most of the basins by 2050 with a rise in evapotranspiration and a decline in precipitation. The increasing trend and uneven distribution of the population and agricultural land upstream/downstream are found to cause the reduction of the PWR available per capita (by 37 %) and agriculture area (by 69 %) across the MRBM. This study predicts water scarcity for most of the basins by 2050, especially in the Mangoro and Onilahy Basins. Upstream populations are expected to grow in Mahajamba, Mahavavy, Betsiboka, Manambolo, Tsiribihina, Mangoro, Onilahy, Mananara, and Mandrare basins, along with an expansion of the downstream agricultural land in Sofia, Betsiboka, Manambolo, Mangoky, and Mandrare basins. These findings enhance the cause-effect relationship between climate change, land use change, population growth, and water scarcity in the MRBM. Urgent action is therefore needed for an efficient and sustainable management of these water-stressed basins. [Display omitted] [ABSTRACT FROM AUTHOR]

• Integrating an agent-based model into a large-scale distributed hydrologic model. • Evaluating the co-evolution of the CNHS at multiple spatial scales. • Demonstrating the trade-off among FEW sectors under climate change. Managing water resources to meet increasing energy and food demands while maintaining environmental sustainability under climate change is a major challenge, especially when this nexus occurred in a coupled natural–human system (CNHS), where heterogeneous human activities affect the natural hydrologic cycle and vice versa. The relevant research has been limited by the lack of models that can effectively integrate human dynamics and hydrologic conditions with spatial details to examine co-evolutionary systems. To address this challenge, this paper develops a modeling framework that integrates an agent-based model (ABM; human behavior model) into a large-scale, process-based distributed hydrologic model to simulate human decisions endogenously in the hydrologic cycle. We then apply the Decision Scaling approach, an ex-post scenario analysis method, with our integrated model to study the bidirectional feedback of the CNHS under future changing climate conditions. With the Columbia River Basin (CRB) selected as the case study area, the calibration results show that the integrated model can simultaneously capture the historical irrigated water consumption and streamflow dynamics. Modeling results show that the trade-off between irrigated water consumption, hydropower generation, and streamflow will become more pronounced under hotter and wetter climate conditions at both the entire basin and regional (states and provinces) levels. Special attention should be given to "temperature thresholds" of different regions when the trade-off pattern started. The trade-off results can potentially inform the Columbia River Treaty renegotiation and provide insights for long-term water management policies. [ABSTRACT FROM AUTHOR]

Frequent drought disasters have significant impacts on socio-economic and ecosystems, and it is crucial to explore the propagation characteristics of drought for disaster prevention and mitigation. In this paper, based on 0.25° × 0.25° grid-point Meteorological hydrological and large-scale climate factor data, the start-to-start, peak-to-peak, and end-to-end drought propagation times, and the periods and rates of drought development and recovery were estimated for 11 regions in the Luanhe River Basin under stationary and non-stationary conditions. The Generalized Additive Model for Location, Scale and Shape (GAMLSS) framework was used to construct stationary and non-stationary models to capture the stationary and non-stationary drought characteristics respectively, and then the drought development and recovery patterns, and drought propagation times were assessed. The results showed that under the influence of climate factors, severe drought events occurred in most study areas, the duration of meteorological drought was prolonged by 0.1–0.6 months, and the peak intensity was increased by about 0.05. The severity of hydrological drought increased by 0.2–0.8, and the peak intensity decreased by 0.1–0.2. The rate of development and recovery of hydrological drought was accelerated by 0.1–0.2 per month. The propagation time of start-to-start was shortened by 0.2 months, and the propagation time of end-to-end was extended by 1–2 months. These mean that water resource control authorities need to propose responses to droughts more quickly. • The non-stationary drought indices considering climatic factors were constructed. • The drought propagation time was calculated from start to start, peak to peak, and end to end. • Quantification of the effects of climate change on drought propagation [ABSTRACT FROM AUTHOR]

• The impact of precipitation, slope, and swamp wetland ratio on water yield is not affected by spatial scale and watershed. • Identifying key areas for ecosystem services combined with multiple scenarios can help to take ecological restoration. • The water yield in the Baihe basin is more sensitive on climate change, while the water yield in the Heihe basin is more easily affected by land use changes. • The economic development and ecosystem services can both be ensured by wetland ecological restoration. Water supply is one of the core ecosystem services functions for wetland. Due to the important status of Zoige wetland, assessment of water supply in Zoige wetland is significant for ecological security all over the world. In this paper, Heihe and Baihe basins in Zoige wetland were taken as research objects, the water yield module of the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model was used to spatially quantify water supply, with the aims of revealing the driving mechanism of water supply under different basins and spatial scale. We observed the spatial pattern change of water yield under baseline and eleven future scenarios and used the ANOVA of repeated measures and multiple linear regression model to explore the patterns and driving factors of water supply in Heihe and Baihe rivers basins. The research results were as follow. (1) The precipitation is main factor to improve water yield, but this intensity is different in different basins and spatial scale. Topography, climate, vegetation, and percentage of wetland conditions have important impacts on water yield services. However, the impacts of these conditions on water yield were various significantly across different watersheds and spatial scales (excluding factors such as precipitation, slope, and percentage of swamp wetland). (2) The spatial pattern of water yield main was affected by land use change and the amount of water yield main was affected by future climate change. (3) Water yield in the Baihe basin was more sensitive to climate change, while the Heihe basin is more sensitive to land use changes. Wetland ecological restoration strategies can effectively improve regional water yield, especially in the Heihe basin. (4) In all scenarios, the southeast regions of the study region were both the main hot spots of water yield. Wetland ecological restoration strategies have added hot spots in the north regions of the Baihe river basin, reduced hot spots in the middle-south regions of the Heihe basin. [ABSTRACT FROM AUTHOR]

This paper proposes a framework based on the integration of bottom-up and top-down approaches to assess and quantify the effect of local climate change on carbon and water fluxes in a protected Mediterranean mixed forest. The forest, with an extent of 50 ha, is in a coastal zone and is in decline because of severe summer drought stress. Since 2018, it has been involved in the LIFE PRIMED ecological restoration project. The bottom-up approach used gas exchange measurements and the MOCA model (MOdelling for Carbon Assessment) to quantify photosynthesis and transpiration of the main species in the forest (P. latifolia , P. lentiscus , Q. cerris , and F. angustifolia sub. oxycarpa). The top-down approach used the satellite models C-fix and NDVI-CWS, to quantify and spatialise gross primary production (GPP), net primary production (NPP), and evapotranspiration (ETA) at the forest stand scale. The up-scaling process from leaf to forest stand was made possible by calibrating two key parameters: light use efficiency (ε) and vegetation transpiration coefficient (Kc veg). The results indicate a decline in GPP , NPP , and ETA during the study period (2018–2022) due to the summer drought conditions caused by rising temperatures (16.60 °C in 2018 vs. 16.98 °C in 2022), increased vapor pressure deficit, reduced soil water content, and rainfall (1328 mm in 2018 vs. 468 mm in 2022). In 2018, the annual GPP was 1186.83 ± 351.40 gC/m2y, which decreased to 1128.67 ± 331.21 gC/m2y in 2022. During the dry summer period, GPP ranged from 401.76 ± 119.54 gC/m2y in 2018 to 347.39 ± 101.62 gC/m2y in 2022. Annual ETA rates varied between 1184.86 ± 351.86 mmH₂O/m2y (2018) and 1304.92 ± 384.07 mmH₂O/m2y (2022). The summer ETA rates were significantly influenced by drought conditions, decreasing from 638.73 ± 190.67 mmH₂O/m2y in 2018 to 390.35 ± 108.83 mmH₂O/m2y in 2022. Based on the observed trend in other Mediterranean areas, species-specific responsiveness to local climate change suggests that P. latifolia and P. lentiscus , which are better adapted to water-limited environments, could gradually replace Q. cerris and F. angustifolia subs. o xycarpa. This study provides useful quantitative indications for the management and restoration goals of the area and suggests a methodology that can be applicable in several management practices, particularly for small heterogeneous and fragmented forested areas such as the Mediterranean ones. • High temperature and reduced rainfall influence forest carbon and water fluxes. • Soil Water Availability negatively affects GPP, NPP and ETA trends. • Leaf and stand scale data are analysed through bottom-up and top-down approaches. • Specific light use efficiency (ε) and crop transpiration coefficient (K veg) are used to calibrate satellite-based models. [ABSTRACT FROM AUTHOR]

The complicated interrelationship between water and energy makes the water-energy dilemma a complex challenge to be tackled, especially considering the tradeoffs among decision-makers at different hierarchical levels and multiple uncertainties derived from climate change, socio-economic development, technical improvement and decision-making preferences. Thus, a water-energy nexus planning framework would be established in this paper to assist optimal decision-making with bi-level programming and multi-uncertainty. By integrating the regional climate model, multiple linear regression, and bi-level interval flexible programming, an integrated prediction optimization model would be developed as the core of the water-energy nexus planning framework. Then it is applied to planning Zhengzhou City over fifteen years. Multiple scenarios based on electricity demand-supply and carbon dioxide emission satisfaction degrees are analyzed leading to the results of (1) compared to the conventional single-level optimization method, the developed model can achieve the hierarchical goals of water saving and economic suitability; (2) renewable energy will be largely developed and its ratio to electricity generation will reach [26.30, 27.51] % under the limited water availability. Overall, the proposed water-energy nexus planning framework can achieve a balanced water-energy dilemma considering bi-level decision-making preferences and multi-uncertainties, which can be applied to planning water-energy nexus systems at a similar scale. • Regional climate model is used for predicting future electricity demands. • The proposed model addresses bi-level and multi-uncertainty. • Water-energy dilemma towards two different hierarchical levels is assessed. • Optimal solutions provide insights for managing similar scale studies. [ABSTRACT FROM AUTHOR]

• Erratic rainfall and temperatures are causing local water sources in Cameroon to disappear, decline or become unreliable. • Water unavailability increases women's domestic and farm workload but reduces their socio-economic productivity and income. • A proper local land management plan on urbanization and deforestation will reduce women's vulnerability to climate change. • Men's participation in reproductive work lessens the load on women and cause men to value the fight against climate change. • Women's local climate adaptation efforts require a comprehensive national climate strategy for maximum effectiveness. Many rural communities in Cameroon rely on natural sources of water (rivers, springs, and rainfall) for agriculture and domestic use. Access to and reliability of water from these sources depend on changes in rainfall and temperatures. Household roles in Cameroon are traditionally defined along gender lines, with women playing key roles in food production, home management, and caregiving. Water is indispensable for women to successfully accomplish these roles. Climate variability is affecting reliability of water in Cameroon; however, impacts are not the same for men and women in rural communities. This paper examines how climate-induced water challenges adversely affect women's ability to perform their multiple roles in a predominantly farming community in southwest Cameroon. Data collected by survey from a hundred women, supplemented by interviews with local water and agricultural technicians, suggest that climate change has contributed to the disappearance of several water sources and decreased volume of others. This hampers local water availability, compromises women's productivity, and increases the burden on women's triple roles as farmers, caregivers, and home managers. Although individual women are implementing some adaptation strategies, comprehensive public policy measures, including promotion of better land use management and gender-sensitive technologies, are vital to sustain efforts against climate change in Cameroon. [ABSTRACT FROM AUTHOR]

• Developed a Decision Support Framework to classify uncertainties and management options using participatory scoping for scenarios analysis. • DSS includes: reservoirs water balance, statistical downscaling, hydrological modelling, sediment assessment, water management and decision support for water management plans. • DSS framework was applied to Tandula reservoir Complex, India and performance was evaluated using multi-criteria decision support in the three-layer hierarchal process. • DSS framework provides a solution for strategic water resources planning and management in a basin using the participation of farmers, technocrats, and water resource managers. The climate uncertainties, data scarcity, and socio-techno challenges pose significant threats and options respectively to the future planning of complex water projects in developing countries. This paper attempts to develop a decision support system (DSS) framework to classify uncertainties and management options using participatory scoping for scenarios analysis with the aid of six interrelated modules namely (i) water balance of reservoirs for computation of runoff (ii) statistical downscaling for climate projection (iii) hydrological modelling (iv) sediment assessment (v) water management and (vi) decision support for the assessment of the performance of multiple management plans designed for three future assessment periods of 2020-35, 2046-64 and 2081-99. The proposed framework was applied to the Tandula complex system of Chhattisgarh state of India consists of three reservoirs namely Tandula, Kharkhara, and Gondli having water transfer in their commands and for industrial use. The developed DSS framework provides the opportunity to analyze the management plans with climate uncertainties for the complex water resources projects having data scarcity. Here, in the present paper, the developed DSS framework incorporates eighty-four diverse management plans devised from constant interaction with stakeholders and technocrats resulting to deal with climate uncertainties using possible improvement in efficiencies and consumptive use for three future assessment periods. Furthermore, the performance of the developed plans was evaluated using multi-criteria decision support in the three-layer hierarchal process. The decision support analysis suggested that the second assessment period (FP-2: 2046-64) will be more crucial from the management point of view where 54 out of 81 plans could not perform as par with the present performance of the system. The developed DSS framework provides a solution for strategic water resources planning and management under projected climate scenarios in a basin having problems of scarcity, surplus, and non-uniform distribution of surface water using the participation of farmers, technocrats, and water resource managers. [ABSTRACT FROM AUTHOR]

Climate variability and insufficient irrigation are primary constraints to stable and higher agricultural productivity and food security in Nepal. Agriculture is the largest global freshwater user, and integration of surface- and ground-water use is frequently presented as an strategy for increasing efficiency as well as climate change adaptation. However, conjunctive management (CM) planning often ignores demand-side requirements and a broader set of sustainable development considerations, including ecosystem health and economics of different development strategies. While there is generic understanding of conjunctive use, detailed technical knowhow to realize the CM is lacking in Nepal. This article presents a holistic framework through literature reviews, stakeholders consultations and expert interviews for assessing CM and implementation prospects from a systems-level perspective. We demonstrate the framework through a case study in Western Nepal, where climatic variability and a lack of irrigation are key impediments to increased agricultural productivity and sustainable development. Results show that knowledge of water resources availability is good and that of water demand low in the Western Terai. Additional and coordinated investments are required to improve knowledge gaps as well as access to irrigation. There is therefore a need to assess water resources availability, water access, use and productivity, to fill the knowledge gaps in order to pave pathways for CM. This paper also discusses some strategies to translate prospects of conjunctive management into implementation. • Customized framework development for assessing prospects for conjunctive management. • Conjunctive management status in western Nepal assessed by applying the framework. • Knowledge on water availability and demand are moderate and low, respectively. • Additional and coordinated investments required to improve access to irrigation. [ABSTRACT FROM AUTHOR]

Policies on bioeconomy are some of the key emerging ones around the world to support sustainability in terms of using renewable resources. However, these may lead to significant demand for biomass feedstock which relies on limited resources, viz., water, land, and energy. The impact of climate change on water availability makes it more challenging. This paper demonstrates the analysis of the water, energy, and food resource nexus of a bioeconomy-based industrial complex and future climate change impact. The model structure consists of cultivation, crop processing, and urban sectors. Sugarcane is the major crop in the case study area and is the main bioeconomy crop. The results indicate that the average sugarcane yield will be lower than the minimum industrial goal for the 2020s and 2030s decades. Consequently, sugarcane feedstock shortage may often occur. The drought situation tends to be increased, so groundwater resources can be the main reserve source of water. In all improvement scenarios on water supply management, nexus energy used for water acquisition was mainly for groundwater acquisition. Direct energy use in the cultivation process is high and fossil fuels based, while most of the energy used in processing came from biomass waste. This implies that technologies for water acquisition will be more important in the future and should be developed in terms of energy efficiency and the aspect of promoting the usage of renewable energy to reduce greenhouse gases and fossil fuels use. The impact of climate change will cause significant fluctuations in the annual rainfall characteristics of the study area. An additional irrigation water supply of about 250 mm and expansion to cover more than 90% of the cultivation area should be considered to secure the minimum supply of sugarcane for the local biorefinery complex in the following decades. [Display omitted] • Integrate climate change impact to Water-Food-Energy nexus model for bioeconomy. • The water–crop yield response model was set up to analyze interventions for improving yield. • In all scenarios, nexus energy used for water acquisition was mainly for groundwater acquisition. • The area will face a water supply shortage in the 2020s, and groundwater is the primary reserve source. • The irrigation expansion to cover 90% of the cultivation area can secure the supply of sugarcane. [ABSTRACT FROM AUTHOR]

Climate models and ongoing monitoring studies predict the remaining glaciers in Africa are predicted to disappear by the middle of the 21st Century. These will likely be the only glaciers present on the continent for some tens of thousands of years, until the next global ice age. This paper considers the implications of the shrinking cryosphere in Africa for the surrounding environment and local communities. Glacier retreat will give rise to significant and irreversible downstream effects on East African mountain landscapes in future decades, including impacts on water resources; slope stability and geohazards; ecosystems and ecosystem services; and human socioeconomic and cultural activities and heritage. This foresight study is the first to discuss future environmental impacts of deglacierization in East Africa, and this is framed around understanding the interconnections that exist between physical and human landscape elements in mountainous regions. A key outcome is the identification of elements of mountain systems that are most sensitive to environmental disturbance as a result of global warming, such as long-term water availability and processes that give rise to geohazards, and highlighting the need for management and mitigation of these varied impacts. • Glaciers in East African mountains are rapidly melting. • These will be the only glaciers present in Africa until the next global ice age. • Glacier retreat will result in significant and irreversible downstream environmental effects. • Most affected will be regional water resources, geohazards, and ecosystem services. • Change in mountain landscapes will impact on socioeconomic and cultural activities. [ABSTRACT FROM AUTHOR]

• We modify a method to assess yield of carryover reservoir with environmental flow. • The method can be applied at large scales, under historic and future climates. • We quantify yield declines due to climate change and environmental flow provision. Protecting freshwater systems to ensure sustainability requires diagnosing threats over a broad range of scales, from local to global. There is growing acceptance that environmental flows must be protected to sustain river channels and floodplain ecosystems downstream of reservoirs. Meeting environmental water requirements has proven difficult because they reduce water yield available for human use – a particular challenge in regions already experiencing declining water availability with climate change. A further challenge is the difficulty of assessing the impact of environmental water requirements on water availability for other purposes. This paper provides a modification of the Gould-Dincer method to assess the yield of carry-over reservoirs subject to environmental water requirements. The method characterizes reservoir inflows using readily available flow characteristics (annual mean and C v). We develop and test the method using ten examples with well-understood environmental water requirements and a range of annual flow C v s. We then demonstrate this method at continental scale, to investigate the impact on yield of providing high-reliability supply including environmental water requirements, under a changing climate. According to our results, considering climate change and environmental flow provision simultaneously, the decline in water yield is projected to be about 27% and 18% respectively for Australia and US (based on hypothetical reservoirs capacity of one times mean annual inflow). Adapting environmental flow demands to future hydrological conditions results in a 2% and 3% increase in Australia and US-wide yield for human use respectively. While further testing is needed, the method provides a simple and rapid way to estimate the impact of providing environmental flow on yield, applicable at global scale. [ABSTRACT FROM AUTHOR]

• Removal of GEDI outliers and water level evaluation. • Bias adjustment between mission ICESat-2 and GEDI. • Water level dynamics from integrating ICESat-2 and GEDI. • Water levels cross validation with DAHITI and Hydroweb datasets. • Factors that affecting the accuracy of water level monitoring. The water levels of inland lakes on the Tibetan Plateau are extremely sensitive to global climate change and can objectively reflect the temporal and spatial changes in local water resources. However, monthly and seasonal variations in lake water levels are difficult to monitor due to the lack of sufficient in situ gauges across mountainous areas. Moreover, GEDI products exhibit large uncertainties in mountainous surroundings. In this paper, taking Qinghai Lake as an example, we first refined the raw data of the GEDI and ICESat-2 missions by implementing a quality control procedure involving outlier removal tailored to the characteristics of each mission; then, we analyzed the accuracy of each mission, especially targeting factors that affect the water level retrievals in the GEDI products. Third, the bias between the two missions was adjusted by selecting the overlapping or adjacent observation dates. Finally, we constructed dense temporal water-level data by integrating the refined ICESat-2 and GEDI data. Data from water level stations and the DAHITI and Hydroweb datasets were also utilized for validation. The results show that (1) very accurate results can be obtained from the ICESat-2 ATL13 product, and the standard deviations of most observed days are under 0.05 m; (2) the GEDI products derived from algorithm 2 can offer more effective footprints than those from algorithm 1, with an improvement of approximately 9.78 %. Moreover, large differences exist among the different GEDI beams, and beams 1 and 2 are recommended for further analysis. Overall, most beams overestimated the lake levels with a bias of 0.264 ± 0.357 m; (3) the long-time-series water levels showed a mean increasing trend of 0.243 m/yr from 2018 to 2021. The relatively high-water-level periods were distributed mostly in August and September, while the low-water-level periods were distributed mostly in February and March. The combined water levels were very correlated with the DAHITI and Hydroweb datasets, with R values larger than 0.8, and highly consistent with the observations from hydrological stations (the inter-year change range spanned from 0.015 m to 0.327 m, and the intra-year difference range varied from 0.03 m to 0.16 m); and (4) Integrating the GEDI and ICESat-2 missions allowed us to capture the monthly, seasonal and annual dynamics of the lake water level, and the results indicate that the combined dataset presents a valuable resource for hydrological and climatic change studies. [ABSTRACT FROM AUTHOR]

Water is exposed to various types of stressors. There are environmental stressors or anthropogenic stressors, which have direct and/or indirect impacts on climate change. The overall objective of this paper is to develop a pioneer simple tool that can measure the water resources vulnerability due to environmental and anthropogenic factors. The tool is developed under six stages. Stage-1: A list of 28 indicators pertinent to the present work are generated; Stage-2: The indicators are assorted into two main categories, namely, environmental and anthropogenic indicators; Stage-3: Indicator weights are suggested using expert elicitation procedure; Stage-4: Index formulation is performed consecutively; Stage-5: The proposed index is applied; Stage-6: An appropriate adaptation strategy is proposed to each specific country. The developed tool is applied to the Limpopo River basin using 28 indicators. Results show that both the environmentally and anthropogenically driven vulnerability of the four riparian countries are moderate ranging from 41.98% in Mozambique to 47.69% in South Africa. The value of indicators ranges from 0.93% to 98.81% in environmentally driven vulnerability and ranges from 0.00% to 97.66% in anthropogenically driven vulnerability. Climate change is thought to increase the vulnerability of water resources by 9.47% in Mozambique to 13.56% in South Africa. The developed tool can be applied to other river basins and countries elsewhere considering indicator weight. [ABSTRACT FROM AUTHOR]

In recent years, the impacts of climate change and socio-economic development on the water-energy-food nexus have been a hot topic. Forecasting future food and energy production and water withdrawal trends under a range of climate and socio-economic scenarios is a critical step for formulating agricultural, industrial, and environmental policy. However, published studies are imprecise due to the complexity of the changeable environment and nexus system. Here we conducted a systematic review and meta-analysis based on 97 studies (1253 observations) published before September 2021 to evaluate the effects of climate change factors on food yield and irrigation water, as well as the influence of socioeconomic development on energy production and water withdrawal. The study shows that the most serious impact of climate change on food yield occurred under the RCP8.5 scenario, with an average decrease of 1.73%, 4.17% and 4.56% in the 2020s, 2050s, and 2080s, respectively. Similar to the prediction of food yield, the irrigation water requirement of food production under the influence of climate change in the RCP8.5 scenario (12.22–18.01%) is higher than that in RCP4.5 and RCP2.6. Under the five socio-economic future scenarios, the average energy generation is projected to increase from 77.41 EJ (2010) to 334.11 EJ (2100). Water withdrawals for electricity generation range from 347 km3 (SSP1) to 1263 km3 (SSP5). Population and GDP were significantly and positively correlated with power generation and water withdrawal (P < 0.001). To some extent, increases in CO 2 concentration and precipitation could compensate for the negative impact of rising temperatures on food yield. Climate change, as well as economic and social growth, will provide substantial challenges to the future water-energy-food nexus. In particular, the water resource risk at its core will create significant uncertainty in the future water-energy-food nexus. To ensure the security and stability of the nexus, we advocate for quick adoption of innovative technologies as well as a multi-sectoral, coordinated strategy for adaptation. We believe that the findings of this paper will provide effective and reliable data support for future policy formulation. [Display omitted] • Effects of climate change and socio-economic on WEFN were evaluated using meta-analysis. • For every 1 ℃ increase in average temperature, food yield will decrease by 1.6%. • Electricity generation is positively correlated with population and GDP growth. • Future WEFN's challenges and the adaptation strategies are proposed. • The application of meta-analysis increased the reliability of research results. [ABSTRACT FROM AUTHOR]

[Display omitted] • Wildfires are becoming more severe and frequent and their effects increasingly expose water resources to stress. • Climate, wildfire, streamflow records (1975 to 2018), topography, and landcover data from 92 catchments were combined to quantify the contribution of wildfire to streamflow variability across Australian temperate forests. • On average wildfire regimes relatively results in 8.8% increases in streamflow across Australian temperate forests. • Wildfire effects on regional streamflow varied spatially depending on hydroclimate factors, particularly precipitation. As wildfires become more frequent and severe, there are concerns regarding their impacts on water yield from forested catchments. While there are many studies in Australia about the effects of individual wildfires on streamflow at fine scales (<1 km2) in specific geographic settings, the effects of wildfire regimes on streamflow at broad spatial scales across temperate forests in Australia are not well understood. In this paper, we combined climate, wildfire, streamflow records (1975 to 2018), topographic, and landcover data from 92 catchments (74 – 4740 km2) in the Australian temperate zone to quantify the contribution of wildfire regimes over time to streamflow variability in different hydroclimatic settings (humid, dry sub-humid, and semi-arid) and geographic regions (Southeast Australia (SEA), Southwest Western Australia (SWWA), and Tasmania (TAS)). Wildfire regimes were represented by two metrics: the burnt area to drainage area (BDA) ratio for wildfire events in each year and a spatially averaged metric of Time Since Fire (TSF), which is a spatial average of time since the last wildfire in the catchment. By comparing prefire and postfire runoff ratios our study found that on average there was a short-term increase in runoff ratio (∼3% in year 1 and ∼6% in year 2 post-fire) after wildfires with BDA > 25%. No influence of fire was found in the long-term (15–20 years after the wildfire) runoff ratio. We found that wildfire regime, measured by TSF, explained ∼8.8% of the variation in annual streamflow across the Australian temperate zone, and that with decreasing TSF (i.e., increased wildfire impact), the average streamflow increased. Streamflow variation explained by wildfire regimes varied with hydroclimate. The explained variance of streamflow by wildfire regimes in semi-arid catchments (23%) and dry sub-humid catchments (13%) were higher than humid catchments (5%). Our results provide a broad-scale understanding of how wildfire regimes influence streamflow variability at broad temporal and spatial scales, and provided important context and baseline information for determining the implications of changes in climate and fire regimes for regional water availability. [ABSTRACT FROM AUTHOR]

• A hydrological modeling approach was proposed to distinguish the relative contribution of climate changes and human activities on Daihai Lake's recession. • In the absence of natural runoff and human-induced water withdrawal observations, the natural state's lake water storage changes were reconstructed. • Without considering the high water years, the anthropogenic factor took the responsibility for the lake shrinkage about 58%, while the climatic factor took roughly about 42% in period 1974–2018. • This investigation serves as a useful example of applying a distributed model to the assessment of lake hydrology, especially for the lake catchments with limited observations. In recent decades, water levels in many closed inland lakes over north-western China experienced severe declines, among which the Daihai Lake in Inner Mongolia, China was particularly significant. Remotely sensed investigations indicated that the Daihai Lake had shrunk approximately 64% in an area with the dramatic decline of water level approximately 9 m from the 1980 s to 2010 s, which has caused serious concern on the sustainable development of the surrounding region. Consequently, several previous studies have concentrated on the possible causes of lake shrinkage. However, predicting climate variability and anthropogenic activities' relative contributions to lake water decline is challenging due to the lack of direct water consumption upstream and watershed-scale natural runoff observations. In this paper, a hydrological modeling approach was presented to quantitatively evaluate and separate the relative contributions of climate variations and intensifying anthropogenic activities. The simulation accuracy was evaluated through comparisons with observed data and cross-validation with previous studies. Based on a baseline period, the natural streamflow draining into the lake was reconstructed using the model. The results revealed that the water loss of the Daihai Lake was caused predominately by human activities rather than climate variability. Specifically, for wet conditions, the climate factors posed a negative effect on the water level decline of the lake and delayed the shrinking process of the lake area. The anthropogenic factors took a dominant role (roughly 58%) of lake shrinkage at the annual average scale for normal and dry conditions, while the climate factors accounted for approximately 42%. Hence, the rational policy for water resource management, ecological restoration, and dam and reservoir constructions/operations should be the essential precautions for sustainable development of the Daihai Lake and its surroundings. Additionally, the hydrological modeling approach adopted in this investigation serves as a useful example of the quantitative assessment of climate variations and human activities, especially for the ungauged catchments. [ABSTRACT FROM AUTHOR]

• The mean groundwater table depth in China dropped by approximately 0.2 m (P < 0.01) during 1979–2018. • The Noah-MP land model forced with reanalysis climate data can reasonably capture terrestrial water and radiation processes across China. • Incorporating the groundwater lateral flow process enhances the seasonality of modeled terrestrial water and radiation processes on a regional scale. Faced with intensified climate change and ever-increasing water demand, the groundwater table depth is vital to sustaining terrestrial environments in a country such as China; however, on a regional scale, insufficient research has been conducted on its variability thus far. Using a land model forced with reanalysis climate data, this paper investigates groundwater table depth changes across China for the 1979–2018 period. The results show a significant overall reduction in the groundwater table depth in China during the past 40 years without explicit consideration of direct human influence. There is an approximately 0.2 m decrease on average, but it is approximately 0.5 m in southern China and 0.8 m to the north of 35°N despite a 1.2 m rise in part of this region due to an increasingly wet climate and a topographic water convergence. The findings provide a first-order pattern of historical groundwater table responses to climate change, highlighting inherent links among subsurface-surface-atmosphere water cycles and worsened terrestrial water availability in China. A model evaluation compared with in situ observations has demonstrated the model's ability to realistically portray terrestrial water and energy balances on regional scales, as well as the enhancement of their seasonality with incorporated lateral groundwater flow processes. This ability gives us reasonable confidence in the simulated trends and spatial variability. Nonetheless, the mean groundwater table still shows large biases relative to observations, and the problems of human influence, two-way interactions between groundwater and surface water, and local topographical complexity have yet to be properly addressed in the present study and deserve further research. [ABSTRACT FROM AUTHOR]

Currently, agriculture uses about 70–80% of global water resources and, in the Mediterranean area, it accounts for the high pressure of freshwater demand. This study provides a useful framework for the meso-level assessment of the Water Footprint (WF) in agriculture. Particularly, the WF methodology is used to quantify the water consumption and pollution of olives, grapes and tomatoes, traditional crops widespread both in the Apulia region, in Southern Italy, and in the Mediterranean area. Hence, from a meso-level assessment of the Water Footprint of Apulian agriculture, a general level of evaluation of the use of Mediterranean water resources was provided, estimating the Virtual Water (VW) too. Furthermore the climate change effects on the Water Footprint of the traditional crops identified were predicted, proposing some scenarios useful to reduce the grey component, which values for olives were evaluated by a sensitivity analysis. The results highlight that olives present the highest value of the WF and that grapes are the most affected by the variations according to the climate change scenarios, increasing over 200% of the green component and 77% of the blue one. Finally, a Circular Economy proposal, based on the reuse of the wastewater from a meso-scale perspective, highlights saving up to 70% of the water resource. The research questions proposed displayed the novelty of this paper, particularly as concerns the use of the Water Footprint analysis on a meso-level evaluation. Particularly, the new insights of this research addressed the needs of stakeholders in areas suffering from drought, such as the Mediterranean, to integrate and systematize a data-set of indicators to rationalize and plan water resource usage and safety in agriculture. [Display omitted] • Water stress spurs Water Footprint assessment in the Mediterranean area. • Multi-level approach of water quantifying for olive, grape and tomato is applied. • Italian grapes have the highest Virtual Water, compared to Spanish and Greek ones. • Effects of climate change on Water Footprint of traditional crops are estimated. • Grey Water Footprint of the olives is evaluated by a sensitivity analysis. [ABSTRACT FROM AUTHOR]

• DRASTIC-AgLU-CC is applied to examine future groundwater contamination risk. • Climate and land use factors are treated as dynamic model inputs. • The influence of land use scheme complexity on model output is assessed. • Detailed agricultural land use representation may improve model predictions. • Predicted contamination risk varies depending on land use representation. Rural regions, which are commonly reliant on groundwater for water supply, often face groundwater quality challenges related to agricultural activity. To sustainably manage and protect groundwater resources, it is necessary to have a clear understanding of inherent groundwater vulnerability and the contamination risk posed by pollutant loading. Index-based methods typically assess groundwater contamination risk in a static manner and commonly represent agricultural land as a single land use class despite the complexity of land management practices that may be present. This paper illustrates modification of the conventional DRASTIC-LU methodology, through a newly developed DRASTIC-AgLU-CC approach, to better understand how groundwater contamination risk may change by mid-century while simultaneously examining the potential influence of land use scheme complexity on model performance and prediction. Recharge, depth to water table, and land use are treated as dynamic factors through the integration of downscaled global climate model data, empirically estimated water table fluctuation and recharge, and trend-based land change modelling. The Upper Parkhill watershed in southwestern Ontario, Canada serves as a case study for method application. Study results indicate that more detailed agricultural land use representation, specifically the inclusion of crop rotation and tile drainage data, has the potential to improve model predictive ability; furthermore, predicted future changes in groundwater contamination risk may vary depending on the manner in which land use is represented. Within the Upper Parkhill watershed, mid-century land use and climate conditions may increase groundwater contamination risk, although minimal change is anticipated. The presented approach provides a valuable screening tool to better understand the potential for changing groundwater contamination risk in rural regions and can be used to guide groundwater monitoring programs and water supply development. [ABSTRACT FROM AUTHOR]

• IBIS may be more impacted by climate change in UIB than local hydrology. • Sedimentation combined with climate change exacerbates dry season water shortages. • Water availability reductions in the dry season could impact Pakistan's food security. Pakistan relies greatly on the water of the Upper Indus basin (UIB) for its vast agriculture in the Indus Basin Irrigation System (IBIS). There are already concerns about the extent of unsustainable water use in the IBIS, particularly of groundwater, and these concerns are likely to increase in the future due to population increase and associated increased demand for food. In addition, climate change, continuing reservoir sedimentation in the major dams, and other impacts on water supply and demand are likely to have an impact on the practical implementation of the landmark inter-provincial Water Apportionment Accord (the Accord), which governs surface water allocation in the IBIS. There is, therefore, a need to assess the sustainability of irrigation in light of the potential variations of water availability in the basin under a series of plausible climate change and reservoir sedimentation scenarios. In this paper, we examine the impact of continuing reservoir sedimentation and climate change by 2050 on the water balance of canal commands in the IBIS. Firstly, we used a river system model, the first to include water management rules as in the Accord, to propagate climate induced changes on flows in the UIB and their impact on IBIS flow regulation and canal deliveries (I cw), with and without reservoir sedimentation. Secondly, we used a selection of General Circulation Models (GCMs) that showed skill at simulating the local climate of the IBIS to assess the projected changes to rainfall (P n) and evapotranspiration (ET a). The analysis revealed that water balances in IBIS canal command areas are more significantly affected by changed inflows from the UIB than by localised climate induced changes (i.e. P n and ET a). Continuing reservoir sedimentation in the dams to 2050 will diminish the capacity of the system to store flows during the wet summer Kharif season for its later release in the dry winter Rabi season. This will decrease the supply of I cw in the Rabi season to the downstream IBIS areas in Sindh and Balochistan provinces, and potentially increase supplies in the Kharif season. The impact of reservoir sedimentation on the Rabi water supply (33 mm (13%) decrease in median I cw , equivalent to 1.89 km3), is greater than the impact of projected localised climate change within the IBIS (2 mm (12%) decrease in median P n , equivalent to 0.13 km3). Sedimentation combined with climate change decreases the median I cw by 51 mm (20%, equivalent to 2.91 km3) in Rabi in the low flow scenario and increases it by 48 mm (8%, equivalent to 2.72 km3) in Kharif in the high flow scenario. In the upstream Punjab province, however, reservoir sedimentation will have limited impact by 2050 due to lower ET a in Rabi and the availability of groundwater. Continued reservoir sedimentation beyond 2050 will also affect Punjab, again diminishing the supply of I cw in Rabi and increasing it in Kharif. Concurrently, declining I cw could lead to a substantial reduction in crop areas in the Rabi season. To avoid this undesirable scenario, Pakistan needs to explore both demand and supply management options to achieve food and economic security, as well as controlling sedimentation rates in reservoirs. [ABSTRACT FROM AUTHOR]

Water plays a quintessential role in the lives of individuals and communities. In recent decades, population growth, migration from rural to urban areas, industrialization, and climate change have increasingly jeopardized the sustainability of cities, especially in developing countries, including Iran. The purpose of this study is to assess recent and future perspectives for urban water security in Iran. To do so, the paper extends previous water security studies within the region by collecting data on urban water security from a cohort of cities rather than a single location. To assess the state of water security in the recent past, from 2013 to 2019, we introduce a dedicated framework comprised of five dimensions and twelve indicators. In estimating future water resources for Iran in the period up to 2100, ensemble-based hydro-climatic regional climate model projections for RCPs 4.5 and 8.5 were analyzed in time and space. The results show that four of the five dimensions of present-day urban water security, including accessibility, availability, water health and sanitation, and the economic value of water, all demonstrate general improvements in water-related urban infrastructure, whereas the environmental indicator depicts a decreasing trend. Future projected trends for Iran's hydro-climate show a general decline in its net availability from already scarce conditions and also increased variability due to climate change. In general, the study indicates both advances in Iran's urban water security recently and severe implications for future water availability in certain regions and periods in the decades to come. The study also advises policymakers to seek to mitigate the water crisis in so far, as also enforced by climate change, by increasing the appropriate infrastructure and using new technologies in the water and wastewater industry. [Display omitted] • A new and recent data set on urban water security indicators in Iran was analyzed. • Twelve indicators formed the novel and combined urban water security index. • Four out of five water security dimensions showed progress during 2013–2019. • The urban water environment dimension showed a declining trend. • Projected future water recourses in Iran is under increasing pressure towards 2100. [ABSTRACT FROM AUTHOR]

• Summer water availability is the main controlling factor of growth of oak species. • Growth response of sessile and Turkey oak to drought differed markedly. • Turkey oak responds sensitively to drought with high recovery potential afterwards. • Sessile oak has lower growth plasticity to droughts than Turkey oak. This paper analyses the drought-induced growth responses of two ecologically and economically important broadleaf tree species, namely sessile oak (Quercus petraea (Matt.) Liebl.) and Turkey oak (Quercus cerris L.) in south-western Hungary. Although both have been described as drought‐tolerant species, our understanding of their growth responses to drought extremes is still limited. Forest stands of younger ages of the target species were sampled along a precipitation gradient under similar soil conditions. 136 tree-ring samples were used to build six species- and site-specific chronologies. We also applied several dendroecological metrics to assess the drought sensitivity of the species. Water deficit was estimated by various drought indices including the soil water-budget based water stress index. The results indicated a strong dependency of annual tree-ring width of both species on the water availability of summer months in the actual year of ring formation. However, we found markedly different reaction of the two species against drought conditions. Turkey oak responded more sensitively to droughts than sessile oak revealed by the significantly lower resistance and higher recovery potential of this species. The more plastic behaviour of Turkey oak could be also perceived by the higher sensitivity of its tree-ring chronologies and by the observed relationship between resistance and recovery that showed a closer fit to the line of full resilience in case of this species. Regarding the precipitation gradient, a linearly proportional increase of growth reduction with rising water stress was found for Turkey oak while the growth response of sessile oak decreased considerably with increasing aridity indicating lower growth plasticity of sessile oak to droughts there. Based on our findings it seems that Turkey oak copes better with droughts than sessile oak and may gain competitive advantages under the projected climate change in Hungary. [ABSTRACT FROM AUTHOR]

• Hydrological responses to land use and climate change are simulated using integrated modelling. • Scoring method is applied to select representative climate models. • Mean temperature is likely to increase by 1.79 °C (3.57 °C) under mid (high) emission scenarios. • Annual and monsoon flow is likely to increase during the 2050s and 2080s. • Hydrological sensitivity of the basin is analysed against changes in climatic variables. Accurate spatial and temporal measurement of water budget play a crucial role in achieving the sustainable planning and management of water resources. This paper presents a comprehensive integrated approach to simulate hydrological responses under dynamics of land use land cover (LULC) and climate change scenarios over Upper Narmada Basin, India. In order to select the representative climate models, scoring method was applied at regional scale. Best five performing climate models (MIROC5, CNRM-CM5, MPI-ESM-LR, GFDL-ESM2G and IPSL-CM5A-MR) were coupled with semi-distributed hydrological model to simulate the hydrological responses. Considering the heterogeneity of the large basin, multi-site calibration and parameters sensitivity analysis were performed using Sequential Uncertainty Fitting (SUFI-2) algorithm. To compute the hydrological sensitivity against land use change, calibrated model was coupled with historical and futuristic land use scenarios (1990, 2000, 2010 and 2030). The results indicate intensified precipitation towards the late 21st century, whereas annual mean temperature could be raised by 1.79 °C and 3.57 °C under mid and high emission scenarios respectively, at the end of century. Annual and monsoon flow in the basin likely to increase during the 2050 s (2041–2070) and 2080 s (2071–2100). Moreover, the relation between climate variables and water budget components were identified to analyse the hydrological sensitivity of the basin under changing climate. [ABSTRACT FROM AUTHOR]

• Food security in Jiangsu can be ensured by improving crop water and nutrient use efficiency. • Water and nutrient use efficiency can be improved by adapting human agency. • Conditions with more water and land, and less population, labor more important than machinery. • Under unfavorable conditions, machinery more important for higher crop production. Food security is important for human well-being worldwide. However, changing climate, population growth and shrinking land resources are threatening food security in many regions of the world. Jiangsu Province, China, is one such region. It is a major food-producing region of the country but is witnessing rapid population growth and urbanization that is putting pressure on agricultural water and land resources and threatening food security of the region. This paper interprets the nexus between regional water availability and food security in Jiangsu Province under different climate change and socio-economic scenarios of population growth and land resource availability. Climate change scenarios are generated based on historical data and Global Climate Model (GCM) products. Socio-economic scenarios are generated based on population growth and crop planted area projections. The uptake of water and nutrients are considered as two dominant biophysical processes of crop growth and food production. Complementing it is human agency, including human labor, irrigation and land-preparation machinery, which are the factors behind water and nutrient use efficiencies of crops grown. Two dominant crops are considered, rice and wheat, that contribute to 61.4% of total crops produced in the province. Results show that adaptation by human agency is necessary to ensure that food supply meets at least the demand of the province under all climate change and socio-economic scenarios. Under relatively favorable scenarios, labor could replace land-preparing machinery since the level of food production can be easily maintained with abundant water and land availability. Mechanization in agricultural production significantly increases food production under unfavorable conditions, since it improves water and nutrient use efficiencies and leads to higher crop yields. This demonstrates that human agency plays an important role in securing food under stressful scenarios of drier climate, population growth, and contraction of agricultural lands. [ABSTRACT FROM AUTHOR]