Search

Groundwater resources are vital for water security but face threats from overexploitation, contamination, and climate change. This study focuses on the Guarani (GAS) and Bauru (BAS) aquifer systems' recharge in western São Paulo, Brazil. We enhanced the scalability of the potential recharge (PR) method and assessed recharge using groundwater storage (GWS) data from the Gravity Recovery and Climate Experiment (GRACE). Our findings indicate that while the remote sensing-based PR method aligns with the existing literature, it tends to overestimate recharge. Conversely, the GWS method provides more conservative and reliable estimates. Integrating remote sensing-based methods is a crucial tool for improving recharge estimation and supporting groundwater resource management. [ABSTRACT FROM AUTHOR]

Increasing interest in solute transport phenomena in agricultural systems on a sub‐annual basis necessitates a better understanding of seasonal changes in natural systems and how these changes can be incorporated into modelling. A better understanding of the seasonal timing of nutrient loading in tile drained agricultural systems in particular is essential for efforts trying to replicate or predict the occurrence of harmful algal blooms. Literature exists showing there are seasonal dynamics (freeze–thaw, plant‐root processes, land management practices, etc.) that may cause changes in the hydraulic properties of the soil zone including hydraulic conductivity and porosity. To test whether these changes are important in an agricultural system, a MODFLOW‐6 model using the unsaturated zone flow package was constructed. The simulation was comprised of separate, seasonal models to be run sequentially with each year being broken into a winter and summer seasons. As part of this architecture, model parameters representing soil hydraulic properties were allowed to vary by season. The model was calibrated against soil moisture observations at multiple depths using a genetic algorithm machine learning technique. The parameters of the sub‐models were compared for the winter and summer seasons. Brook‐Corey epsilon, saturated vertical conductivity, saturated volumetric water content and residual volumetric water content were found to be consistently different between the modelled summer and winter periods. A more traditional model which did not allow hydraulic properties to vary seasonally was also run and compared to the seasonal architecture and the seasonal architecture was found to improve simulation results. The hydrologic dynamics of the unsaturated zone—particularly in tile drained agricultural systems—control the residence time for water and solutes, which is critical for in‐field chemical processes such as denitrification. This work has important implications for seasonal transport phenomena in agricultural systems and improving the simulation and prediction of harmful algal blooms. [ABSTRACT FROM AUTHOR]

With increasing shallow groundwater use for agricultural purposes, understanding the spatiotemporal variability in recharge rates, storage capacity, and its interaction with surface waters becomes crucial for its sustainable management. An integrated SWAT-MODFLOW model is developed to assess shallow groundwater availability in the Borkena catchment. The model is calibrated using streamflow and static groundwater level data. Results show that groundwater recharge in the catchment is 85 mm/a, representing 11% of the mean annual rainfall. Shallow groundwater resources exist across nearly 42% of the Borkena catchment. The percentage of shallow groundwater withdrawal to groundwater recharge is very low (0.1%), signifying the potential for increased shallow groundwater development. However, caution must be taken as its uncontrolled expansion may result in a high risk of depletion. This integrated modeling is one of the few efforts conducted to provide important information regarding shallow groundwater potential in the Borkena catchment, which is essential for the resilience of small-scale producers in the continued growing water demand and climate change. [ABSTRACT FROM AUTHOR]

Xerophytic vegetation re-regulates and allocates water resources through canopy interception, root water uptake and transpiration, and changes the water budget among precipitation, runoff, interception and infiltration, thus having a significant impact on the processes of the hydrological cycle. In this study, we investigated the effect of xerophytic shrub-Salix on soil water redistribution and water budget through an in situ monitoring experiment combined with two-dimensional vegetation water consumption modeling. The results showed that, due to the interception effect of root water uptake, it was difficult for precipitation infiltration to recharge deep soil water and groundwater. The measured data of soil moisture content, hydraulic head and precipitation were used to verify and calibrate the performance of the soil water flow model in the vadose zone by HYDRUS-2D. The effect of roots system on soil water was simulated, and the appropriate spacing of Salix replanting was estimated. Combined with the relationship between the transverse roots system and the crown width obtained by the investigation, it was determined that the spacing between the Salix should be greater than five times the crown width, so that the balance between the water consumption of Salix and the water supply of deep soil by precipitation could be considered. The results of this study are important for estimating groundwater recharge in arid areas and provide practical vegetation replanting options for similar regions. [ABSTRACT FROM AUTHOR]

Water balance quantifies the inflows and outflows in a river basin, crucial for assessing the water resources of a given area. Quantified water balance should therefore be the key step in environmental quality assessment. However, due to the lack of data on reasonable spatiotemporal scales and quality, water balance studies are scarce. The aim of the paper was to provide a water balance analysis as a prerequisite for aquatic and wetland ecosystems management in the Biebrza Valley, Poland. A Penck-Oppokov method was used to assess the annual water balance, and runoff coefficient for 1951–2021. Data were extracted for the daily simulated dataset of Poland. The average annual water balance of the Biebrza basin encompassed of 561 mm of precipitation, 485 mm of evapotranspiration, 101 mm of runoff, and −25 mm of water retention. Analysis of 17 sub-basins indicated a declining tendency in water resources over the study period. The average runoff coefficient in the Biebrza basins is equal to 0.17. Findings presented here indicate that the significant deficit in the water balance in the region is highly unlikely to be compensated by the course of natural hydrological processes. This reveals the need for quick actions oriented at improvement of water balance by reducing the runoff and evapotranspiration. The study provides convincing evidence that if the observed tendencies of water balance elements are continued, the reinstallation of spatially distributed, abundant measures of increasing water retention may be the only way to assure the appropriate ecological status of aquatic and wetland ecosystems. [ABSTRACT FROM AUTHOR]

Copyright of Egyptian International Journal of Engineering Sciences & Technology (EIJEST) is the property of Egyptian International Journal of Engineering Sciences & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ground freeze‒thaw processes have significant impacts on infiltration, runoff and evapotranspiration. However, there are still critical knowledge gaps in understanding of hydrological processes in permafrost regions, especially of the interactions among permafrost, ecology, and hydrology. In this study, an alpine permafrost basin on the northeastern Qinghai‒Tibet Plateau was selected to conduct hydrological and meteorological observations. We analyzed the annual variations in runoff, precipitation, evapotranspiration, and changes in water storage, as well as the mechanisms for runoff generation in the basin from May 2014 to December 2015. The annual flow curve in the basin exhibited peaks both in spring and autumn floods. The high ratio of evapotranspiration to annual precipitation (>1.0) in the investigated wetland is mainly due to the considerably underestimated ‘observed’ precipitation caused by the wind-induced instrumental error and the neglect of snow sublimation. The stream flow from early May to late October probably came from the lateral discharge of subsurface flow in alpine wetlands. This study can provide data support and validation for hydrological model simulation and prediction, as well as water resource assessment, in the upper Yellow River Basin, especially for the headwater area. The results also provide case support for permafrost hydrology modeling in ungauged or poorly gauged watersheds in the High Mountain Asia.

Novel soil datasets and the application of pedotransfer functions provide soil hydraulic input data for modelling hydrological processes at different scales. We aimed to evaluate the reliability of soil hydraulic parameters derived by indirect methods in simulation of soil moisture time series and water budgets at profile level of three sites (Forest, Orchard and Grassland) from a Central European catchment (Lake Balaton, Hungary). Five soil-vegetation-atmosphere model variants were set up with the Hydrus-1D model for each site, differing only in the parametrization of input soil data: i) a calibrated reference, ii) measured values, iii) values predicted from measured basic soil properties, iv) values predicted from national soil map information, v) values derived from the 3D soil hydraulic dataset of Europe. Calibrated soil parameters led to Nash-Sutcliffe efficiency 0.50, 0.54 and 0.71 for the Forest, Orchard and Grassland Site respectively. The outcomes for model efficiency of soil moisture underline the superiority of local databases over regional ones and the need for more detailed vertical discretization during modelling. The model performance according to soil moisture and water budget accuracy led to different rank order of model variants. Water budget comparisons indicated moderate differences between the hydrologic fluxes simulated by the different model variants, emphasizing the uncertainties associated with soil hydraulic parametrization either at local or at watershed scale.

Nitrate leaching from farmland pollutes the surrounding environment, such as groundwater, causing health hazards to inhabitants. To mitigate the leaching, biochar can be applied. The effect of biochar application differs depending on the application depth; however, the effect of the application depth remains unclear. To evaluate the effect, we conducted a pipe experiment with no plant using bagasse biochar with four treatments: no biochar application, surface application (0−5 cm), plow layer application (0−30 cm), and subsurface application (25−30 cm). The results showed that surface and plow layer applications reduced nitrate leaching, whereas subsurface application did not affect leaching. This difference was due to changes in the soil water movement and water budget. Surface application reduced evaporation, inducing increases in both drainage and the amount of water in the pipe. The increased amount of water might contribute to an increase in the amount of nitrogen in the pipe, reducing the leaching. Plow layer application increased evaporation, leading to decreased drainage and nitrate leaching. Subsurface application did not affect drainage and nitrate leaching; however, the change in the volumetric water content at a depth of 10 cm was the most significant among the treatments. Our study indicated that, although the same amount of biochar was applied, the effect of biochar application differs depending on the application depth. [ABSTRACT FROM AUTHOR]

Major theoretical and practical hydrological issues may be solved using methods to maintain water balance. Evaluating the climate characteristics and environmental circumstances to be employed in the methods of water managing approach used in the Erbil sub-basin, northern Iraq, is the primary goal of this study. The studied area is a part of the region influenced by the Mediterranean climatological system. The climatic parameters of the research region were evaluated using the climatic data collected in the Erbil meteorological station for the period 1980-2022. The research result shows that the mean annual rainfall is 411.26 mm/year and the average monthly relative humidity is 41.12 %, the mean temperature is 20.62 °C, mean sunshine duration 8.35 hr./day and annual pan evaporation is 1200.96 mm / year. Potential evapotranspiration considered by Thornthwaite method is 1588.94 mm. The water surplus and deficit are 216.14 mm and 1393.81 mm, respectively. The surface runoff calculating from soil conservation system (SCS) technique which is about 86 mm / year and groundwater recharge is about 130.14 mm / year. The groundwater 3 Budgets is about 187661880 m³ / year. The climatic situation in the area is variety from winter its wet to the summer its dry climates. Also, it could be measured that the climate in the area is determined was (Humid to very humid). The draught index according to SPI analysis show that the drought was observed during Moderately drought in (1983, 1999, 2000, 2010, 2015, and 2021) to severely drought in (2022. [ABSTRACT FROM AUTHOR]

Potential impacts of projected long-term climate change toward the end of the 21st century on rainfall and peak intensity of six super-typhoons in the western North Pacific (WNP) are assessed using a cloud-resolving model (CRM) and the pseudo-global warming (PGW) method, under two representative concentration pathway (RCP) emission scenarios of RCP4.5 and RCP8.5. Linear long-term trends in June–October are calculated from 38 Coupled Model Intercomparison Project phase 5 (CMIP5) models from 1981–2000 to 2081–2100, with warmings of about 3 °C in sea surface temperature, 4 °C in air temperature in the lower troposphere, and increases of 20% in moisture in RCP8.5. The changes in RCP4.5 are about half the amounts. For each typhoon, three experiments are carried out: a control run (CTL) using analysis data as initial and boundary conditions (IC/BCs), and two future runs with the trend added to the IC/BCs, one for RCP4.5 and the other for RCP8.5, respectively. Their results are compared for potential impacts of climate change. In future scenarios, all six typhoons produce more rain rather consistently, by around 10% in RCP4.5 and 20% in RCP8.5 inside 200–250 km from the center, with increased variability toward larger radii. Such increases are tested to be highly significant and can be largely explained by the increased moisture and water vapor convergence in future scenarios. However, using this method, the results on peak intensity are mixed and inconsistent, with the majority of cases becoming somewhat weaker in future runs. It is believed that in the procedure to determine the best initial time for CTL, which yielded the strongest TC, often within a few hPa in minimum central sea-level pressure to the best track data, an advantage was introduced to the CTL unintentionally. Once the long-term trends were added in future runs, the environment of the storm was altered and became not as favorable for subsequent intensification. Thus, the PGW approach may have some bias in assessing the peak intensity of such super-typhoon cases, and caution should be practiced. [ABSTRACT FROM AUTHOR]

Hydraulic redistribution (HR) is a common phenomenon in water‐limited ecosystems; however, it remains unclear how the volume of water transported via HR compares to other components of the hydrologic budget and how HR influences water availability for understory plant communities. In this study, we investigate the absolute and relative magnitude of HR on a forest water budget and identify potential impacts of this water subsidy to understory plant communities. We scaled tree‐level estimates of transpiration and HR of three common tree species naturally occurring in a longleaf pine woodland with plot‐level measurements of basal area to determine their magnitude at the stand scale. We trenched plots containing understory vegetation but devoid of mature trees and their connected roots to exclude HR subsidies to understory plant species. We analysed soil water isotopes and assessed leaf water potential (ΨL) in trenched and control plots to determine if HR results in mixing of water among soil strata and improves understory plant moisture status. Water inputs from HR were equivalent to >30% of total rainfall for the site during the observation period and ~40% of total tree water uptake, depending on species. A stable isotope mixing model confirmed that soil water within HR‐exposed plots was more similar to groundwater, whereas soil water within trenched plots was more similar to precipitation. Exclusion of HR via trenching decreased soil moisture and pre‐dawn ΨL for all understory species. These three lines of evidence suggest that HR from overstory trees redistributes a sizable portion of water from deeper to shallower soil profiles and that this water subsidy enhances understory plant water status. [ABSTRACT FROM AUTHOR]

The hydrogeological system of the Bajos Submeridionales (BBSS), a large plain in Argentina, remains insufficiently understood. The BBSS is located in the distal part of one of the largest fluvial megafans in the Gran Chaco Plain, South America. The BBSS is sparsely populated and frequently affected by extreme drought and flood events that cause severe problems to communities and economic production. This research aims to improve the current hydrogeologic understanding of the system through the development of the first integrated hydrogeological model for the region. The BBSS hydrogeological system exhibits a relatively simple hydraulic behavior at a regional scale. The definitions of four hydrogeological units (HU) were based on the simplification of the sedimentary column for the area, representing the fundamental characteristics of the dynamics of groundwater flows, their interconnections and the interactions with surface-water bodies and the atmosphere through direct recharge. Due to the lack of available transient data, the hydrogeological conceptual model was numerically tested under a steady-state flow regime. The numerical model was instrumental to test the plausibility of the proposed conceptual model and evaluate the water balance components for the entire aquifer system. The numerical model highlighted the role of stream/aquifer interaction as a primary discharge mechanism and the occurrence of flow exchanges between HUs. A newly installed groundwater monitolring network will support future transient simulations to investigate the temporal evolution of the system and explore management interventions to achieve environmental sustainability criteria. [ABSTRACT FROM AUTHOR]

The Abijata-Langano-Ziway Lakes Basin (ALZLB) is situated in the Central part of the Main Ethiopian Rift. The availability and dynamics of groundwater in the Abijata-Langano-Ziway Lakes Basin (ALZLB) are primarily controlled by its geological and hydrogeological characteristics, shaped by volcanic-tectonic and sedimentary processes. The basin faces significant challenges, including drastic change in land use pattern, rapid population growth sustained by subsistence farming, over-extraction of water resources, and vulnerability to climate change and fragile ecosystems. These issues emphasize the urgent need for effective water resource management.To understand this complex system, a numerical groundwater flow model was employed to characterize the groundwater flow system within the ALZLB and examine its interaction with surface water bodies. The MODFLOW model translates the conceptual understanding of the basin's hydrogeology into a mathematical representation, allowing for numerical analysis. The model incorporates input parameters such as hydraulic conductivity and boundary conditions representing groundwater inflow and outflow. Steady-state numerical calculation was used to characterize the qualitative hydrogeological conceptual model into numerical representation and thereby describe the groundwater system.The calibrated model exhibited excellent agreement between simulated and observed groundwater levels. Statistical measures indicated a strong correlation (R2 = 0.98) and high efficiency (NSE = 0.97) in replicating the observed data. Additionally, the Mean Error (ME) of −8.3 m suggests minimal bias in the simulations. Further analysis of the histogram residuals revealed that a significant portion of the simulated values (65 % and 82 %) fell within ±20 m and ±30 m of the observed groundwater levels, respectively. This revealed the model's accuracy in capturing the groundwater system's behavior.The model identified groundwater recharge and constant head boundaries as the primary sources of groundwater inflow, contributing 445 million cubic meters per year (MCM/year) and 90 MCM/year, respectively. Conversely, constant head boundaries represented the most significant outflow pathway, with a simulated discharge of 519 MCM/year. The calibrated balance between inflow and outflow (discrepancy of −0.75 %) confirms that the model effectively simulates steady-state groundwater flow conditions. The calibrated model demonstrates the model's capability to accurately represent the basin's groundwater system.

Remote sensing-based surface energy balance algorithms have been used to estimate water use of various crops. However, citrus evapotranspiration (ET) estimation is challenging mainly due to evergreen leaves and a clumped canopy structure. In this study, we evaluated the performance of two methods for calculating ET: the ensemble of OpenET models, which are mostly satellite thermal-based models, and the BAITSSS water and energy balance model. Calculated ET was compared with (i.) eddy covariance (EC) ET measurements and (ii.) water received (irrigation plus precipitation) data for two citrus orchards in San Joaquin Valley, California. Polaris-based soil hydraulic properties and measured volumetric water content were used for BAITSSS parameterization and initialization, respectively. Sentinel-2 based NDVI was used for BAITSSS simulation. Results showed that annual ET based on the OpenET ensemble model (1169 mm) was on average 30 % larger (r2 ∼ 0.71, RMSE ∼ 1.16 mm) than both EC ET (908 mm) and water received (886 mm). The disparity mostly occurred in spring. BAITSSS, on the other hand, showed mixed results compared to observations (r2 ∼ 0.77, RMSE ∼ 0.94 mm). Both measured from EC and modeled ET from BAITSSS and ensemble OpenET values were below grass reference ET (ETo) for the majority of the simulation period. Soil moisture and water received data indicated the orchards may have been deficit irrigated. Overall, this study highlights the challenges of ET modeling in citrus orchards and the need for improved estimation of ET for this specialty crop.

Major theoretical and practical hydrological issues may be solved using methods to maintain water balance. Evaluating the climate characteristics and environmental circumstances to be employed in the methods of water managing approach used in the Erbil sub-basin, northern Iraq, is the primary goal of this study. The studied area is a part of the region influenced by the Mediterranean climatological system. The climatic parameters of the research region were evaluated using the climatic data collected in the Erbil meteorological station for the period 1980-2022. The research result shows that the mean annual rainfall is 411.26 mm/year and the average monthly relative humidity is 41.12 %, the mean temperature is 20.62 °C, mean sunshine duration 8.35 hr./day and annual pan evaporation is 1200.96 mm / year. Potential evapotranspiration considered by Thornthwaite method is 1588.94 mm. The water surplus and deficit are 216.14 mm and 1393.81 mm, respectively. The surface runoff calculating from soil conservation system (SCS) technique which is about 86 mm / year and groundwater recharge is about 130.14 mm / year. The groundwater Budgets is about 187661880 m3 / year. The climatic situation in the area is variety from winter its wet to the summer its dry climates. Also, it could be measured that the climate in the area is determined was (Humid to very humid). The draught index according to SPI analysis show that the drought was observed during Moderately drought in (1983, 1999, 2000, 2010, 2015, and 2021) to severely drought in (2022.

Study region: Alpine shrubland on the northeastern Qinghai-Tibetan Plateau. Study focus: Water provision ability is a pivotal ecological service of high-altitude alpine regions and is controlled by precipitation, evapotranspiration (ET), and soil water storage whereas the underlying ecohydrological processes remain highly unquantified. Here, we investigated continuous 19-year flux measurements to quantify the temporal patterns of ET and water budget (precipitation minus ET, P−ET), as well as 0-20 cm soil water storage change (ΔSWS). New hydrological insights for the region: At a monthly scale, ET peaked in July (96.7 ± 26.4 mm, Mean ± S.D.) and averaged 41.7 ± 31.9 mm, whose variations were determined by the slope of the saturation vapor pressure curve at air temperature, air and soil temperatures, regardless of vegetation growth stage. P−ET averaged 18.3 ± 26.3 mm in August and September while stayed deficit during the other months. The variations in P−ET were controlled by precipitation in the May-October growing season whereas by ET in the non-growing season from November to April. ΔSWS peaked in May (28.8 ± 11.2 mm) and September (3.0 ± 2.7 mm) and almost accumulated to zero over the whole season. At annual scales, none of ET, P−ET, and ΔSWS changed significantly. ET averaged 512.2 ± 68.4 mm and exceeded precipitation (459.1 ± 58.4 mm), likely due to the lateral flow supply of uphill locations. The variations in ET were regulated directly by bulk canopy resistance and indirectly by net radiation. P−ET averaged −53.2 ± 95.4 mm and demonstrated a clear water deficit (−51.6 ± 21.0 mm) during the non-growing season. The variations of P−ET were driven jointly by precipitation and ET, with opposite but equivalent effects. The dominance of thermal conditions and energy availability on ET variability manifested an energy-limited feature of water loss in the alpine shrubland. The temporal patterns in P−ET elucidated that the alpine shrubland plays the water retention rather than water provision function through transforming variable precipitation input into stable ET loss.

We investigate historical simulations of relevant components of the Arctic energy and water budgets for 39 Coupled Model Intercomparison Project Phase 6 (CMIP6) models and validate them against observation-based estimates. We look at simulated seasonal cycles, long-term averages and trends of lateral transports and storage rates in atmosphere and ocean as well as vertical fluxes at top-of-atmosphere and the surface. We find large inter-model spreads and systematic biases in the representation of annual cycles and long-term averages. Surface freshwater fluxes associated with precipitation and evaporation as well as runoff from Arctic lands tend to be overestimated by most CMIP6 models and about two thirds of the analysed models feature an early timing bias of one month in the runoff cycle phase, related to an early snow melt bias and the lack of realistic river routing schemes. Further, large biases are found for oceanic volume transports, partly because data required for accurate oceanic transport computations has not been archived. Biases are also present in the simulated energy budget components. The net vertical energy flux out of the ocean at the Arctic surface as well as poleward oceanic heat transports are systematically underestimated by all models. We find strong anti-correlation between average oceanic heat transports and mean sea ice cover, atmospheric heat transports, and also the long-term ocean warming rate. The latter strongly suggests that accurate depiction of the mean state is a prerequisite for realistic projections of future warming of the Arctic. Our diagnostics also provide useful process-based metrics for model selection to constrain projections. [ABSTRACT FROM AUTHOR]

A very detailed water budget analysis was conducted on Lake Trafford in South Florida. The inflow was dominated by surface water influx via five canals (61%), with groundwater influx constituting 12% and direct rainfall constituting 27%. Lake discharge was dominated by sheet flow (69%) and evapotranspiration (30.5%), with groundwater recharge of the hydraulically connected unconfined aquifer accounting for only 0.5%. The removal of 30 M tons (4.4 × 106 m3) of organic sediment impacted the groundwater influx, causing enhanced groundwater flow into the deeper parts of the lake and mixed flow along the banks, creating a rather unusual pattern. The large number of groundwater seepage meters used during this investigation led to a very reliable set of measurements with occasional failure of only a few meters. A distinctive relationship was found between the wet-season lake stage, heavy rainfall events, and pulses of exiting sheet flow from the lake. Estimation of the evapotranspiration loss using data collected from a weather station on the lake allowed the use of three different models, which, when averaged, produced results comparable to Lake Okeechobee (South Florida). A limitation of this investigation was the inability to directly measure sheet-flow discharges, which had to be estimated as a residual within the calculated water budget. [ABSTRACT FROM AUTHOR]

Observation-based climate model evaluation and future projections help policymakers in developing action plans for efficient management of water resources and mitigation of the impacts of hazardous extremes. Apart from this socioeconomic importance, the scientific value cannot be overstated, especially in light of the upcoming Fifth U.S. National Climate Assessment (NCA) report. In this study, we evaluate the realism of hydroclimate variability in the historical simulations of a suite of coupled general circulation models (CGCMs) participating in the fifth and sixth phases of the Coupled Model Intercomparison Project (CMIP5 and CMIP6). Our results demonstrate systematic biases in the simulated seasonal precipitation-most prominently, wet bias over the mountainous western United States in winter, and dry bias over the U.S. central plains in summer. A distinctive feature of this work is our focus on the examination of the atmospheric water budget, in particular the relative importance of remote and local contributions-convergence of moisture fluxes and local land surface processes (evapotranspiration) respectively-in helping produce precipitation. This diagnosis reveals that the leading contribution of the remote influence in winter is overestimated by the CMIP6 multimodel mean (MMM), whereas the local influence, which is more influential in summer, is underestimated. Our results aid in understanding the drivers of seasonal precipitation over the United States, where precipitation will likely increase by the end of the century but with significant model disagreement for the summer and fall. In support of ongoing NCA efforts, our study aims to contribute a comprehensive, regional-level analysis of the moisture budget and emphasizes the importance of realistically simulating its major components in CGCMs.

Abstract Lake Van, the greatest soda water lake in the world located in the east of Turkey, has always attracted the attention of researchers due to its significant water level changes. Identifying the causes for these level changes is very important with respect to the scientific world and the sustainability of the ecological balance. Although extensive research has been carried out on the water level changes in Lake Van in the past years, no any study exists which analyzes the recent level changes. In this study, recent water level changes in Van Lake were analyzed using two different methods, and the results were evaluated. First, the water level changes during the period 2010–2020 were examined through the meteorological and hydrological data collected by the water budget method. Second, the water level changes for 2000–2020 were estimated using the LSTM and NAR neural networks. In the light of the results, reasons for the recent level changes in Lake Van were discussed. It was concluded that the changes, especially those occurred after 2014, may be hydrometeorological. However, the unusual level changes between 2010 and 2013 cannot be explained by water balance, may be tectonic or volcanic origin. The findings of this study indicate that these changes may continue in the future, and therefore, further research with different disciplines is needed on this subject.

Every facet of life, including human habitation, economic development, food security, etc., depends on water as a valuable resource. Due to the burgeoning population and rapid urbanization, water availability needs to be simulated and measured using hydrologic models and trustworthy data. To fulfill this aim, the SWAT model was processed in this work. The SWAT model was formulated to estimate the hydrological parameters of Yeralwadi using meteorological data from IMD (India Meteorological Department) for the period 1995-2020. The observed discharge data was collected from the HDUG Nasik group and used in the calibration and validation of the Model. The SWAT model was corrected & validated through the SUFI-II algorithm in SWAT-CUP to get a better result. The model's sensitivity is checked by using statistical parameters like Nash-Sutcliffe Efficiency (NSE) and a coefficient of determination (R²). NSE values were 0.72 and 0.80 in calibration and validation, and R² were 0.80 & 0.76 in calibration and validation, respectively, indicating the acceptance of the model. Results show that 40.6% of the total yearly precipitation was lost by evapotranspiration. The estimated total discharge from the Yeralwadi catchment was 55.6%, out of which 41.2% was surface runoff and 14.4% was baseflow. The other 17.8% was made up of percolation into confined and unconfined aquifers, which served as soil and groundwater storages. The surface runoff is influenced by Curve number (CnII), SOL_AWC, ESCO, and base flow was influenced by ALPHA-BF and GW_REVAP. This study will be useful to water managers and researchers to develop sustainable water resource management and to alleviate the water scarcity issues in the study basin. [ABSTRACT FROM AUTHOR]

Hydrology and meteorological data from relatively undisturbed watersheds aid in identifying effects on ecosystem services, tracking hydroclimatic trends, and reducing model uncertainties. Sustainable forest, water, and infrastructure management depends on assessing the impacts of extreme events and land use change on flooding, droughts, and biogeochemical processes. For example, global climate models predict more frequent high-intensity storms and longer dry periods for the southeastern USA. We summarized 17 years (2005–2021) of hydrometeorological data recorded in the 52 km2, third-order Turkey Creek watershed at the Santee Experimental Forest (SEF), Southeastern Coastal Plain, USA. This is a non-tidal headwater system of the Charleston Harbor estuary. The study period included a wide range of weather conditions; annual precipitation (P) and potential evapotranspiration (PET) ranged from 994 mm and 1212 mm in 2007 to 2243 mm and 1063 in 2015, respectively. The annual runoff coefficient (ROC) varied from 0.09 in 2007 (with water table (WT) as deep as 2.4 m below surface) to 0.52 in 2015 (with frequently ponded WT conditions), with an average of 0.22. Although the average P (1470 mm) was 11% higher than the historic 1964–1976 average (1320 mm), no significant (α= 0.05) trend was found in the annual P (p = 0.11), ROC (p = 0.17) or runoff (p = 0.27). Runoff occurred on 76.4% of all days in the study period, exceeding 20 mm/day for 1.25% of all days, mostly due to intense storms in the summer and lower ET demand in the winter. No-flow conditions were common during most of the summer growing season. WT recharge occurred during water-surplus conditions, and storm-event base flow contributed 23–47% of the total runoff as estimated using a hydrograph separation method. Storm-event peak discharge in the Turkey Creek was dominated by shallow subsurface runoff and was correlated with 48 h precipitation totals. Estimated precipitation intensity–duration–frequency and flood frequency relationships were found to be larger than those found by NOAA for the 1893–2002 period (for durations ≥ 3 h), and by USGS regional frequencies (for ≥10-year return intervals), respectively, for the same location. We recommend an integrated analysis of these data together with available water quality data to (1) assess the impacts of rising tides on the hydroperiod and biogeochemical processes in riparian forests of the estuary headwaters, (2) validate rainfall–runoff models including watershed scale models to assess land use and climate change on hydrology and water quality, and (3) inform watershed restoration goals, strategies, and infrastructure design in coastal watersheds. [ABSTRACT FROM AUTHOR]

Although urbanization fundamentally alters water and energy cycles, contemporary land surface models (LSMs) often do not include key urban vegetation processes that serve to transfer water and energy laterally across heterogeneous urban land types. Urban water/energy transfers occur when rainfall landing on rooftops, sidewalks, and driveways is redirected to lawns or pervious pavement and when transpiration occurs from branches overhanging impervious surfaces with the corresponding root water uptake takes place in nearby portions of yards. We introduce Noah‐MP for Heterogenous Urban Environments (Noah‐MP HUE), which adds sub‐grid water transfers to the widely used Noah‐MP LSM. We examine how sub‐grid water transfers change surface water and energy balances by systematically increasing the amount of simulated water transfer for four scenarios: tree canopy expanding over pavement (Urban Tree Expansion), tree canopy shifting over pavement (Urban Tree Shift), and directing impermeable runoff onto surrounding vegetation (Downspout Disconnection) or into an engineered pavement (Permeable Pavement). Even small percentages of sub‐grid water transfer can reduce runoff and enhance evapotranspiration and deep drainage. Event‐scale runoff reduction depends on storm depth, rainfall intensity, and antecedent soil moisture. Sub‐grid water transfers also tend to enhance (reduce) latent (sensible) heat. Results highlight the importance not only of fine‐scale heterogeneity on larger scale surface processes, but also the importance of urban management practices that enhance lateral water transfers and water storage–so‐called green infrastructure–as they change land surface fluxes and, potentially, atmospheric processes. This work opens a pathway to directly integrate those practices in regional climate simulations. Key Points: We develop an urban land surface model representation of impervious to pervious runon and canopy overhanging impervious surfacesUsing idealized land use, we systematically examine the effects of lateral transfers on water and energy budgets over warm seasonsWe found large changes in runoff generation, water balances, and energy partitioning when lateral transfers are simulated [ABSTRACT FROM AUTHOR]

Lake Van, the greatest soda water lake in the world located in the east of Turkey, has always attracted the attention of researchers due to its significant water level changes. Identifying the causes for these level changes is very important with respect to the scientific world and the sustainability of the ecological balance. Although extensive research has been carried out on the water level changes in Lake Van in the past years, no any study exists which analyzes the recent level changes. In this study, recent water level changes in Van Lake were analyzed using two different methods, and the results were evaluated. First, the water level changes during the period 2010–2020 were examined through the meteorological and hydrological data collected by the water budget method. Second, the water level changes for 2000–2020 were estimated using the LSTM and NAR neural networks. In the light of the results, reasons for the recent level changes in Lake Van were discussed. It was concluded that the changes, especially those occurred after 2014, may be hydrometeorological. However, the unusual level changes between 2010 and 2013 cannot be explained by water balance, may be tectonic or volcanic origin. The findings of this study indicate that these changes may continue in the future, and therefore, further research with different disciplines is needed on this subject. [ABSTRACT FROM AUTHOR]

Quantitative delineation of water sources in a large river system is essential for the sustainable use of water. In the present study, we have tested two different methodologies to estimate the contribution from different water sources in the river Ganga. The first model uses stable isotopes and physicochemical parameters of water to delineate the contribution of glacier‐melt, groundwater, and surface runoff in different stretches of the river Ganga. The end member‐based mixing model provides glacier‐melt contribution of ~31.2%, ~5.5%, and ~0.5% in the upper, middle, and lower stretch of the river Ganga. The model showed maximum contribution from groundwater (~66.3%) in the middle stretch and surface runoff (~57.2%) in the lower stretch of the river Ganga. However, the uncertainties in the estimates from the three‐component mixing model were significantly high due to temporal variability in the end member values. To provide estimates with lower uncertainty, an alternate method (discharge dependent budget estimation [DDBE]) has been proposed which delineates the contribution of groundwater and surface runoff in small segments of the river. The DDBE model confines the calculation for budget estimates to smaller segments of the river and hence leads to lower uncertainties in the results, providing improved systematic estimation of water budget for large river systems. In the present study, estimates from the DDBE model suggest that groundwater contributes ~79% of the additional water whereas the contribution from surface runoff is ~21% in the middle and lower stretch of the river Ganga. The DDBE model was successfully applied in 5 small segments along the stretch of the river Ganga and the methodology used shows great potential for systematic delineation of water sources in large river system. [ABSTRACT FROM AUTHOR]

The products from the Stable Water Isotope Intercomparison Group, Phase 2, are currently used for numerous studies, allowing water isotope model‐data comparisons with various isotope‐enabled atmospheric general circulation model (AGCMs) outputs. However, the simulations under this framework were performed using different parameterizations and forcings. Therefore, a uniform experimental design with state‐of‐the‐art AGCMs is required to interpret isotope observations rigorously. Here, we evaluate the outputs from three isotope‐enabled numerical models nudged by three different reanalysis products and investigate the ability of the isotope‐enabled AGCMs to reproduce the spatial and temporal patterns of water isotopic composition observed at the surface and in the atmospheric airborne water. Through correlation analyses at various spatial and temporal scales, we found that the model's performance depends on the model or reanalysis we use, the observations we compare, and the vertical levels we select. Moreover, we employed the stable isotope mass balance method to conduct decomposition analyses on the ratio of isotopic changes in the atmosphere. Our goal was to elucidate the spread in simulated atmospheric column δ18O, which is influenced by factors such as evaporation, precipitation, and horizontal moisture flux. Satisfying the law of conservation of water isotopes, this budget method is expected to explain various fractionation phenomena in atmospheric meteorological and climatic events. It also aims to highlight the spreads in modeled isotope results among different experiments using multiple models and reanalyses, which are primarily dominated by uncertainties in moisture flux and precipitation, respectively. Plain Language Summary: Our study focuses on surface and atmospheric water isotopes, which are crucial for understanding climate and environmental processes. We assessed the performance of different climate models that simulate water isotopes and compared them to real‐world observations. To accomplish this, we employed advanced atmospheric models that include isotopes and subjected them to different input data sets. We discovered that the accuracy of the simulations varied depending on the specific model and data used, as well as the vertical levels considered. By performing correlation analyses at different spatiotemporal scales, we obtained insights into how well the models align with the observed isotopic patterns in both surface and airborne water. Additionally, we utilized a stable isotope mass balance method to examine how various factors, such as evaporation, precipitation, and horizontal moisture flux, influence changes in the isotopic composition of the atmosphere. This method enabled us to identify the sources of uncertainty in the model results. Our research emphasizes the need for a standardized experimental design when studying water isotopes with climate models. By identifying the dominant sources of uncertainty, our findings will prove valuable for scientists from various disciplines and enhance the understanding of simulated future climate and water cycle studies. Key Points: We built a publicly available data set of isotope‐enabled nudged simulations from 1979 to 2020, utilizing three models and three reanalysesWe decomposed atmospheric processes impacting water isotopes, spanning evaporation to precipitation, leading to the first global estimationModeled water isotope spreads due to model and reanalysis choices were dominated by moisture flux and precipitation uncertainties [ABSTRACT FROM AUTHOR]

Copyright of DSI Technical Bulletin / DSİ Teknik Bülteni is the property of DSI Technical Bulletin / DSI Teknik Bulteni and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue TED: Territoires, Environnement et Développement is the property of Universite Ibn Tofail and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to the rapid exploitation of water resources in the Huixian karst wetland in the southwest of China in the past decades, the wetland has suffered from shrinkage in size and serious degradation of ecological functioning. To assess how much water within the wetland could still be taken out for local supply purposes while the wetland can still be kept in its normal ecological functioning. Through the use of multi-methods, including field surveys by a multi-disciplinary team, water balance, Remote Sensing, GIS and numerical simulation, this paper characterizes the wetland regime of the study area and finally determines scenarios of water resource utilization for local water supply within acceptable parameters of wetland ecological health. Through the analysis of the methods, it was found that the hydrological characteristics of the study area were conditioned by not only the karst water but also the regional precipitation fluctuations. A zone of mobile watersheds for Lake Mudong was established as opposed to a conventional single watershed. If the wetland ecosystem is kept at the current status of class III, a scenario of withdrawal of up to 20% of lake inflows could be accommodated. The results and their approaches would provide much-needed information for the protection of the wetland and its sustainable water utilization per se. It would offer a basic reference for similar problems in karst areas of southwest China and other areas alike. [ABSTRACT FROM AUTHOR]

Human activities and extreme hydrological events are posing continuing threats to sustainable management of water resources in Gin catchment, Sri Lanka (972 km2), a rain-fed agriculture-dominated catchment in the tropics which experiences uneven temporal rainfall distribution. This study aims to assess the seasonal water availability in the Gin catchment by setting up of Hydrologic Engineering Center-Hydrologic Modeling System (HEC-HMS) rainfall–runoff model. The HEC-HMS continuous-based simulation performed well with Nash–Sutcliffe efficiency, NSE ≥ 0.72 and percent bias, PBIAS ≤ − 6.8% during the calibration (2011–2014) and validation (2015–2017). The seasonal and annual water balance volumes during 2011–2017 were simulated reasonably well with 10–13% error and 3% error on average, respectively. The modeling results indicated clear seasonal variation with respect to the availability of water depicting 64% of the annual water yield generation in the cultivation seasons, Yala (April–June) and Maha (October–December), dominated by the monsoon rains. The direct surface runoff regime has become the dominant component in the two cultivation seasons (68–70%), and the precipitation loss volume constituted higher percentage in the non-cultivation season (44%) in comparison with the cultivation seasons (28%). Even during the non-cultivation season which coincides with the dry months of the year (January–March and July–September), a significant contribution of baseflow to the total streamflow (40%) was evident which will favorably impact the rain-fed perennial crops. Maintaining the environmental flow requirement, Q90 (≈ 18 m3/s), in the river during the driest month (March) should be given attention in the proposed Gin–Nilwala inter-basin diversion plan in the upstream catchment. [ABSTRACT FROM AUTHOR]

Xerophytic vegetation re-regulates and allocates water resources through canopy interception, root water uptake and transpiration, and changes the water budget among precipitation, runoff, interception and infiltration, thus having a significant impact on the processes of the hydrological cycle. In this study, we investigated the effect of xerophytic shrub-Salix on soil water redistribution and water budget through an in situ monitoring experiment combined with two-dimensional vegetation water consumption modeling. The results showed that, due to the interception effect of root water uptake, it was difficult for precipitation infiltration to recharge deep soil water and groundwater. The measured data of soil moisture content, hydraulic head and precipitation were used to verify and calibrate the performance of the soil water flow model in the vadose zone by HYDRUS-2D. The effect of roots system on soil water was simulated, and the appropriate spacing of Salix replanting was estimated. Combined with the relationship between the transverse roots system and the crown width obtained by the investigation, it was determined that the spacing between the Salix should be greater than five times the crown width, so that the balance between the water consumption of Salix and the water supply of deep soil by precipitation could be considered. The results of this study are important for estimating groundwater recharge in arid areas and provide practical vegetation replanting options for similar regions.

Potential impacts of projected long-term climate change toward the end of the 21st century on rainfall and peak intensity of six super-typhoons in the western North Pacific (WNP) are assessed using a cloud-resolving model (CRM) and the pseudo-global warming (PGW) method, under two representative concentration pathway (RCP) emission scenarios of RCP4.5 and RCP8.5. Linear long-term trends in June–October are calculated from 38 Coupled Model Intercomparison Project phase 5 (CMIP5) models from 1981–2000 to 2081–2100, with warmings of about 3 °C in sea surface temperature, 4 °C in air temperature in the lower troposphere, and increases of 20% in moisture in RCP8.5. The changes in RCP4.5 are about half the amounts. For each typhoon, three experiments are carried out: a control run (CTL) using analysis data as initial and boundary conditions (IC/BCs), and two future runs with the trend added to the IC/BCs, one for RCP4.5 and the other for RCP8.5, respectively. Their results are compared for potential impacts of climate change. In future scenarios, all six typhoons produce more rain rather consistently, by around 10% in RCP4.5 and 20% in RCP8.5 inside 200–250 km from the center, with increased variability toward larger radii. Such increases are tested to be highly significant and can be largely explained by the increased moisture and water vapor convergence in future scenarios. However, using this method, the results on peak intensity are mixed and inconsistent, with the majority of cases becoming somewhat weaker in future runs. It is believed that in the procedure to determine the best initial time for CTL, which yielded the strongest TC, often within a few hPa in minimum central sea-level pressure to the best track data, an advantage was introduced to the CTL unintentionally. Once the long-term trends were added in future runs, the environment of the storm was altered and became not as favorable for subsequent intensification. Thus, the PGW approach may have some bias in assessing the peak intensity of such super-typhoon cases, and caution should be practiced.

Taditionally, watershed-scale hydrology is simulated by distributed hydrological models with offline meteorological forcing data, or by regional regional climate models that link atmospheric and land hydrology interactions. Global climate model (GCMs) are rarely used to study watershed-scale hydrology due to the relatively coarse grid resolution, computationally expensive downscaling, and simplified physical processes. Recently, however, watershed-scale hydrology analysis has become possible in GCMs due to the development of variable-resolution GCMs that dynamically couple the hydrological processes between atmospheric and land systems at fine resolutions in selected regions and coarse resolution elsewhere. In this study, we used the variable-resolution Community Earth System Model (VR-CESM) with refined-resolution (14 km) in the western U.S. and eastern China to evaluate smaller watershed-scale hydrology. We compared the historical VR-CESM outputs with gauge measurements and other hydrological models (e.g., National Water Model in the U.S.) and calibrated the subsurface runoff capacities in four mountainous watersheds. An RCP8.5 projection from 2007 to 2050 is used to estimate the impact of changing precipitation and snow climatology on watershed hydrology. We also analyzed the long-term runoff variability and the possibility of extreme runoff events as simulated by the VR-CESM. Although calibration is not possible in larger-scale watersheds, VR-CESM simulates the long-term annual variability of watersheds and provides insights on climate change impacts on hydrology. We conclude that refined-resolution VR-CESM can be used for watershed-scale hydrology analysis to understand water resources and water balance, in addition to traditional watershed-scale hydrological models. It enables hydrological analysis at multiple watersheds in one simulation and can help understand the two-way dynamics between land surface hydrology and atmospheric processes, and is especially practical for projecting climate change impacts. However, it is challenging to apply VR-CESM for hydrologic analysis in regulated watersheds as human factors (e.g., pumping, irrigation, water diversion) have not been fully addressed in VR-CESM.

Assessing groundwater recharge is crucial for managing and governing water resources in any region. Indus River Basin (IRB) is an area that relies heavily on canal and groundwater irrigation. The replenishment of groundwater is largely dependent on surface water supplies. The purpose of this research is to determine the amount of groundwater recharge from various sources in Rachna Doab. The study employed the water budget method to calculate seasonal groundwater recharge during the Rabi (October–March) and Kharif (April–September) (Summer) periods from 2005 to 2011. The main components of the recharge were rainfall, water conveyed through channels, and irrigation water applied to cultivated fields. Conversely, the extraction of water from private and public tube wells was the discharge component of the study. Groundwater levels increased during the Kharif season but decreased during the Rabi season. Average recharge contribution from rainfall was 45 and 14% during the Kharif and Rabi seasons, respectively. The total annual recharge from watercourses and irrigation fields was estimated to be approximately 33% of the total recharge. Rainfall was the most significant source of long-term seasonal recharge, followed by watercourses and irrigation fields. In general, the average depletion of the reservoir was 94 million cubic meters per season. HIGHLIGHTS Contribution to groundwater recharge from different sources in Rachna Doab is estimated using water budget method for 2005–2011.; Rainfall contributes to groundwater recharge, i.e., 45% during the Kharif season and 14% during the Rabi season.; Water courses and field irrigation contribute an average of 33% of total recharge.; The groundwater reservoir in the study area is depleted at a rate of 94 MCM per season due to more pumping than recharge.;

Study region: The Nile Delta region consists of flat, low-lying areas, where most areas are used for agriculture. It covers an area of 22,000 km2, which is 2.20% of the total area of Egypt. Study focus: This study evaluates the water budget and the salinity due to the Sea Level Rise (SLR) and the reduction in the river water flow caused by the Grand Ethiopian Renaissance Dam (GERD) using the numerical code SEAWAT. Three filling scenarios were considered for the GERD reservoir at elevations 600 m, 621 m, and 645 m above mean sea level (AMSL) for the storage volumes of 17 billion cubic meters (BCM) (scenarios #1), 37.30 BCM (scenarios #2), and 74 BCM (scenarios #3). The impact of these fillings scenarios was combined with SLR of 25 cm, and increasing the abstraction rates from the Nile Delta aquifer by 25%, 50%, and 100%, respectively. New hydrological insights for the region: The study findings indicated that the SLR and the GERD reservoir filling with increasing pumping rates, especially during the filling periods, would influence the groundwater resources in the Nile Delta. The GERD reservoir filling could alter the freshwater, in which the aquifer salinity increased by 4.47%, 11.48%, and 29.99% for the three scenarios, respectively. The methodology and findings presented in this study might be useful for investing and comparing the impact of SLR and upstream dam projects on the downstream water budget and salinity at other coastal regions.

Xili reservoir is one of the most important drinking water reservoirs in southeast China, ensuring the safety of water supply in Shenzhen city. Understanding the water balance in the reservoir system under climate change and human activities is essential for making optimal water use planning. To assess the water balance of the Xili reservoir system, the water isotope characteristics in rainfall, reservoir water, groundwater, soil, and plant were investigated. The variation of isotope composition in rainfall, reservoir water, and groundwater indicates the different recharging and mixing water sources. A mathematical mass-balance model was established to evaluate the water budget in the Xili reservoir. Roughly 35% of total incoming water was consumed by evaporation, which reminds managers to pay more attention to making scientific planning.

Groundwater plays an important role in our environment. In recent decades, groundwater-related issues within the river basin are significantly increasing in most part of the world. It is essential to estimate the magnitude of groundwater storage changes as well as runoff generated within the river basin. The principal objectives of the study are to quantify the water budget parameters for Baitarani River Basin of India and to analyze the season-wise trend analysis of groundwater storage by using Innovative Trend Analysis (ITA). Climatic data from eight Indian meteorological stations were used to estimate direct runoff from enhanced SCS-CN (Soil Conservation Service Curve Number) method, Potential Evapo-Transpiration (PET) was estimated by using Hargreaves method in R studio platform. The analysis showed that precipitation and surface runoff followed a non-monotonic negative (− ve) trend in winter season and monotonic positive (+ ve) trend in all other season for all stations. It was also observed that the groundwater storage is increasing in winter and post-monsoon season. In the lower catchment areas, groundwater storage was more due to flat topography and good aquifer type, where groundwater use can be enhanced. But in upper catchment areas, groundwater storage capacity is comparatively less hence rain water conservation structures could be suggested to check the surface runoff and provide options for increasing groundwater recharge. This study will be helpful to focus on regional scale planning to address the water management issues within the basin, which will be ultimately helpful for agriculture, watershed development and environmental planning. [ABSTRACT FROM AUTHOR]

Climate change could add a variety of uncertainties to hydrological processes and water resources. Very limited efforts have been devoted to applying the US-EPA (Environmental Protection Agency)'s Hydrologic and Water Quality System (HAWQS) model for predicting climate change impacts on hydrological processes at the basin scale. Here, we applied the model to project the next 50 years' (from 2021 to 2070) hydrological processes at the Yazoo River basin in Mississippi, USA. Simulations showed that over the next 50 years, there are no significant trends in monthly precipitation, ET, runoff and discharge; only 2% of the annual precipitation percolated into the deep aquifer; and dry seasons become dryer and wet seasons become wetter. These findings provide very useful information to stakeholders for water resource management. Our study further suggests that the HAWQS model is a user-friendly and time-saving tool for basin-scale hydrological modelling. [ABSTRACT FROM AUTHOR]

Recently, new numerical methods have been applied to weather data for the estimation of water budget, especially when the lack of measured data is considerable. Geostatistics is one of the most powerful approaches when it comes to studying spatially relevant natural phenomena, as it considers the spatial correlation among measurements over a specific study area and provides the associate uncertainty. In this study, we tested the feasibility of using a geostatistical method to provide a reliable estimation of the water budget of the Foro river basin (Central Italy) by comparing the obtained results with those of a traditional yet robust method. The results obtained with the geostatistical approach proved to be in line with the ones from the traditional method. Additionally, it was possible to quantify the uncertainty associated with the discharge values, making the estimates more reliable than the ones obtained with the traditional approach. However, the yearly distribution of river discharge obtained using both methods appeared to be dissimilar to the measured ones. The surface water uses, as well as the regulatory effect of the carbonate and alluvial aquifer regime, may affect the river discharge variability over the year and then can account for similar discrepancies between the inflow and outflow water volumes. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Forest water dynamics and hydro-chemical characteristics are essential for understanding forest hydrology and ecological processes. Yet, such understanding is limited by a lack of long-term monitoring data and observations from specialized forest ecosystems such as those from high elevation. Here, we analyze the precipitation redistribution including interception, stemflow, and throughfall and hydro-chemical characteristics by using a 15 year (2005–2019) precipitation dataset in a high elevation, evergreen broad-leaved forest in Southwest China. The forest experienced an obvious seasonal variation in precipitation with a monthly average of 117.31 ± 91.21 mm. The precipitation redistribution was influenced by precipitation intensity and leaf area index and differed inter-annually and intra-annually, with a general pattern: throughfall > canopy interception > stemflow. Throughfall rate increased significantly from 2015 to 2019 after experiencing the January 2015 snowstorm. The majority of water within the study site was retained in the soil and apoplastic materials. The primary means of water output was evapotranspiration, with minimal surface runoff. Quality of surface water was affected by the weathering of rocks, resulting in a lower pH than that of atmospheric precipitation. During the rainy season, elemental Ca and Mg showed negative correlation with precipitation due to plant mediation. The other elements, pH, total dissolved solids, precipitation, air temperature, and water temperature showed different degrees of correlation with each other. Overall, while the water balance fluctuated over the past 15 years, the water-holding capacity remained relatively stable. Alkali cations such as Ca2+, Mg2+, and K+ in the water body showed a decreasing trend during 2005–2019, which is a potential threat to ecological stability. [ABSTRACT FROM AUTHOR]

Scarce water resources across the globe have prompted the development of data‐driven water budgets to account for and distribute limited water more effectively across various land uses and purposes. Data‐driven approaches for estimating individual water budget components have been extensively developed and subsequently reviewed (e.g., evapotranspiration, precipitation, groundwater, surface water, runoff), but the state of the art of data‐driven approaches for estimating and integrating complete water budgets has not been the subject of a review paper to our knowledge. In this review, we fill this void by reviewing 81 systematically identified publications from the last decade (2012–2022) on data‐driven water budget approaches. We describe the current state of measurements and data products for data‐driven water budgets for various spatiotemporal scales. Our analysis suggests that spatiotemporal parameters drive the approach for data‐driven water budgets, with larger spatiotemporal scales relying more on satellite remote sensing data products and smaller spatiotemporal scales relying more on ground‐based monitoring. The incorporation of satellite remote sensing data products and ground‐based monitoring was common across various spatiotemporal scales and enabled the estimation of complete water budgets in areas of limited data availability. We conclude that improved reporting of simplifying assumptions, uncertainty analysis methods, and data sources are required for the alignment of water budget estimations between resource managers at varied spatiotemporal scales. Our review calls for the standardization of data‐driven water budget reporting protocols to improve the interpretability of data‐driven water budgets across decision‐makers working at various spatiotemporal scales. Plain Language Summary: Scarce water resources across the globe have prompted the monitoring of water budgets using data, which we refer to as a data‐driven water budget. We review the current state of measurements and data products for data‐driven water budgets of various scales—from field to region and over minutes to decades. We conclude that satellite remote sensing data products are suitable for data‐driven water budgets over large areas and long periods, but ground‐based data are more suitable over small areas and shorter periods. We identify challenges for data‐driven water budgets, which call for standardized reporting protocols for data‐driven water budgets. Key Points: The frequency and spatial scale of data‐driven water budgets differ in the integration of ground‐based and satellite remote sensing dataThe simplifying assumptions, uncertainty, and data sources should be reported in a data‐driven water budgetThe standardization of data‐driven water budget reporting protocols is needed for decision‐makers working at various spatiotemporal scales [ABSTRACT FROM AUTHOR]

Büyük Menderes Basin is one of the largest basins in Turkey, with almost half of the basin area utilized for agricultural purposes. The amount of water allocated to the agricultural areas in the basin corresponds to 80% of water use in the watershed. Hence, the impact of climate change on the water supply in the Büyük Menderes Basin will be significant for the basin. In this study, we model the effects of climate change on the water budget (water supply and demand balance) of the Büyük Menderes Basin using the Water and Evaluation and Planning (WEAP) tool. Future precipitation, temperature, and evaporation data for the basin are attained from outputs of the HadGEM2-ES global circulation model (GCM), along with CNRM-CM5.1 and GFDLESM2M regional circulation models (RCM) for RCP 4.5 and RCP 8.5 scenarios. Subsequently, the study applies different statistical bias correction methods (Linear Scaling (LS), Distribution Mapping (DM), Local Precipitation Scaling (PLIS), and Power Transformation of Precipitation (PTP) for raw outputs of GCMs and RCMs and analyzes the changes in outcomes of projected climate data and the impact of changes on the hydrology of the basin using the WEAP model. For this analysis, calibrated and validated WEAP model for the 12 reservoirs of Büyük Menderes Basin is used to understand the impact of different bias correction methods on reservoir levels. [ABSTRACT FROM AUTHOR]