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A special issue of Water (ISSN 2073-4441). This special issue belongs to the section "Hydrology".

Deadline for manuscript submissions: closed (20 February 2025) | Viewed by 12782

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Prof. Dr. Alina Barbulescu

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Guest Editor

Department of Civil Engineering, Transilvania University of Brașov, 500036 Brașov, Romania
Interests: hydrology; time series analysis; applied statistics; mathematical modeling
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Dr. Romulus Costache

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Guest Editor

National Institute of Hydrology and Water Management, București-Ploiești Road, 97E, 1st District, 013686 Bucharest, Romania
Interests: hydrology; natural hazards; geographic information science; bivariate statistics; machine learning and artificial intelligence applied in the natural hazard’s susceptibility assessment
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Dr. Cristian Ștefan Dumitriu

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Guest Editor

Faculty of Mechanical Engineering and Robotics in Constructions, Technical University of Civil Engineering, Calea Plevnei 59, 021242 Bucharest, Romania
Interests: water quality, environmental modeling, soil pollution, climate change, project management
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Water is an essential element for human life and security. In recent times, the apparition and intensification of extreme events has aggravated water availability and quality, significantly affecting people’s well-being. Drought episodes intensify water scarcity. At the same time, rainfall intensity or frequency has increased in different regions worldwide. In this context, evaluating and forecasting the apparition of extreme events and mitigating their effects has become necessary not only as research topics but especially for policymakers and decision factors to avoid or mitigate the inherent effects of such events. In this context, the main topics of this Special Issue are as follows:

Influence of climate changes in the water runoff process;
Future projection of flash-flood susceptibility according to climate change scenarios;
The variability of the maximum river discharges according to climate change projections;
The impact of climate change on the frequency and severity of droughts;
Risk and uncertainty in detecting drought events;
Quantitative and qualitative analysis of extreme events;
Hazards and risks in drought assessment;
Integrating environmental economics into flood/drought risk management;
Modeling the correlation between climate variables and hydrological processes.

Prof. Dr. Alina Barbulescu
Dr. Romulus Costache
Dr. Cristian Ștefan Dumitriu
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Water is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

climate change scenarios
extreme events
risk assessment
multivariate analysis
artificial intelligence Models

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Related Special Issue

Climate Change and Hydrological Processes, 2nd Edition in Water (5 articles)

Published Papers (12 papers)

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Editorial

Jump to: Research

6 pages, 190 KiB

Open AccessEditorial

Climate Change and Hydrological Processes

by Alina Bărbulescu, Romulus Costache and Cristian Ștefan Dumitriu

Water 2025, 17(10), 1474; https://doi.org/10.3390/w17101474 - 14 May 2025

Viewed by 205

Abstract

In recent decades, many regions have experienced a noticeable increase in the frequency and intensity of extreme events, posing serious challenges to water resource management [...] Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

Research

Jump to: Editorial

27 pages, 5114 KiB

Open AccessArticle

Making Different Decisions: Demonstrating the Influence of Climate Model Uncertainty on Adaptation Pathways

by Jessica Dimond, William Roose and Lindsay Beevers

Water 2025, 17(9), 1366; https://doi.org/10.3390/w17091366 - 1 May 2025

Viewed by 305

Abstract

The total global economic cost of flood damages between 1990 and 2024 exceeds £790 billion, with over half of these losses attributed to flood damages occurring in the last decade alone. Recent severe flood events have prompted a shift in flood risk management towards probabilistic approaches, leading to the notion that flood risk management is a continuous process of adaptive management. While substantial research has been dedicated towards characterising and quantifying climate model uncertainty, less focus has been directed towards the propagation of this uncertainty into hydraulically modelled systems and adaptive decision making. Recently, the concept of adaptation pathways has gained growing interest as a decision-focused, analytical tool to assess climate adaptation scenarios under uncertainty. This research develops an approach to quantify climate model uncertainty across multiple plausible adaptation scenarios and examines its influence on adaptation pathways using the case study area of Inverurie, Scotland. Uncertainty is quantified using stratified sampling and captured across scenarios, resulting in the identification and development of adaptation pathways within the context of specified flood risk management objectives and identified adaptation tipping points. The findings underscore the critical importance of embracing uncertainty in adaptation pathways to support robust, informed decision making. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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21 pages, 3068 KiB

Open AccessArticle

Evaluation of Historical Dry and Wet Periods over Lake Kyoga Basin in Uganda

by Hassen Babaousmail and Moses A. Ojara

Water 2025, 17(7), 1044; https://doi.org/10.3390/w17071044 - 2 Apr 2025

Viewed by 326

Abstract

Rainfall datasets from the Uganda National Meteorological Authority (UNMA) for 1981–2017 and two reanalysis datasets (Climate Hazards Group Infrared Precipitation with Stations data (CHIRPS) and Tropical Applications of Meteorology using Satellite data (TAMSAT) were used to compute drought and flood tendencies from 1981 to 2017. The cumulative departure index (CDI) and rainfall anomaly index (RAI) were computed to show drought and flood tendencies in the region. Meanwhile, dry days (DD) and wet days (WD) were computed based on the definition as a day of the season with rainfall amounts less than 1.0 mm and greater than 1.0 mm, respectively. The CDI graphics indicated below-average rainfall during 1981–1987 and relatively wetter conditions during 1989–1995 for all stations in the region. Generally, seasonal rainfall declined over the first 27 years but an increasing trend in both MAM (March–April–May) and SOND (September–October–November–December) was observed in most stations during 2006–2017. The highly variable seasonal rainfall in the region is expected to impact the livelihoods of the communities. This study recommends that the use of tailor-made weather and climate information for planning economic development programs such as agriculture will play a critical role in improving the livelihood of the communities in the region. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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23 pages, 9504 KiB

Open AccessArticle

Multiscale Factors Driving Extreme Flooding in China’s Pearl River Basin During the 2022 Dragon Boat Precipitation Season

by Jiawen Zheng, Naigeng Wu, Pengfei Ren, Wenjian Deng and Dong Zhang

Water 2025, 17(7), 1013; https://doi.org/10.3390/w17071013 - 29 Mar 2025

Viewed by 274

Abstract

This study delves into the once-in-a-century extreme precipitation events in the northern region of the Pearl River Basin during the 2022 Dragon Boat Festival period. Through a comprehensive analysis spanning various temporal scales, from synoptic-scale systems to subseasonal oscillations, including the rare triple-peaked La Niña phenomenon, we illuminate the intricate interactions among these factors and their impact on extreme precipitation events. Specifically, we present a conceptual model of multiscale interaction systems contributing to extreme precipitation in the BeiJiang Basin. Our findings reveal that, during the 2022 Dragon Boat Festival period, precipitation in the BeiJiang Basin exhibited characteristics across multiple time scales, with the synoptic-scale environment proving highly conducive. Systems such as the South Asian High, Western Pacific Subtropical High, and South China Sea summer monsoon were identified as the direct influencing factors of precipitation. Importantly, our study highlight the pivotal role of subseasonal oscillation propagation stagnation in extreme precipitation in the BeiJiang Basin, with synoptic-scale systems playing a contributing role. We emphasize the indirect influence of ENSO signals, regulating not only monsoons but also the propagation of subseasonal oscillations. The interplay of these factors across different temporal scales significantly impacts flood hazards. Overall, our study significantly enhances the understanding of mechanisms driving extreme precipitation events in the Pearl River Basin, with profound implications for water resource management and disaster prevention. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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18 pages, 7074 KiB

Open AccessArticle

Intercomparison of Runoff and River Discharge Reanalysis Datasets at the Upper Jinsha River, an Alpine River on the Eastern Edge of the Tibetan Plateau

by Shuanglong Chen, Heng Yang and Hui Zheng

Water 2025, 17(6), 871; https://doi.org/10.3390/w17060871 - 18 Mar 2025

Viewed by 311

Abstract

This study assesses the effectiveness and limitations of publicly accessible runoff and river discharge reanalysis datasets through an intercomparison in the Upper Jinsha River, an alpine region with substantial hydropower potential on the eastern edge of the Tibetan Plateau. The examined datasets are the European Centre for Medium-Range Weather Forecast Reanalysis version 5 (ERA5-Land), the Global Flood Awareness System (GloFAS), the Global Reach-Level Flood Reanalysis (GRFR), and the China Natural Runoff Dataset (CNRD). These datasets are created using various meteorological forcing, runoff generation models, river routing models, and calibration methods. To determine the causes of discrepancies, additional simulations were carried out. One simulation, driven by meteorological forcing similar to that of ERA5-Land and GloFAS but utilizing the uncalibrated NoahMP land surface model at a higher spatial resolution, was included to evaluate the effects of meteorological inputs, spatial resolution, and calibration on runoff estimation. Runoff from all datasets was rerouted on a high-resolution river network derived from the 3-arcsecond Multi-Error-Removed Improved-Terrain Hydrography (MERIT-Hydro) dataset, allowing for a comparison between vector- and grid-based river routing models for discharge estimates. The intercomparison is grounded in observations from three gauging stations—Zhimenda, Gangtuo, and Benzilan—at monthly, daily, and hourly scales. The results suggest that model calibration has a more significant influence on runoff and discharge estimates than meteorological data. Calibrated datasets, such as GloFAS and GRFR, perform better than others, despite variations in the forcing data. The runoff characteristics-based calibration method used in GRFR exhibits superior performance at Zhimenda and Benzilan. However, at Gangtuo, GRFR’s performance is unsatisfactory, highlighting the limitation of the machine learning-based method in regions with rugged terrain and limited observations. Vector-based river routing models demonstrate advantages over grid-based models. GloFAS, which uses a grid-based routing model, encounters difficulties in simultaneously producing accurate runoff and discharge estimates. The intercomparison shows that GRFR’s river routing is sub-optimally configured. However, when GRFR’s runoff rerouted, the performance of discharge improves substantially, attaining a Kling–Gupta efficiency of approximately 0.9. These findings offer valuable insights for the further development of reanalysis datasets in this region. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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22 pages, 16461 KiB

Open AccessArticle

Water Management Instructions as an Element of Improving the State of the Pakoski Reservoir (Central–Western Poland)

by Bogumił Nowak, Grzegorz Dumieński and Agnieszka Ławniczak-Malińska

Water 2025, 17(3), 403; https://doi.org/10.3390/w17030403 - 1 Feb 2025

Viewed by 737

Abstract

The management of reservoir dams in the context of observed climate changes and changing environmental conditions is becoming an increasingly significant challenge. Changes in the regimes of rivers feeding the reservoirs, sudden floods, long periods of drought, shallowing of reservoirs, water pollution, and algal blooms create unprecedented threats to the operation of these reservoirs. Among these challenges, the most crucial seems to be the proper management of available water resources, which condition the existence of the reservoir. The location of the reservoir has a significant impact on how water management is conducted. In the case of mountain and upland reservoirs created for flood protection of areas downstream, water management practices differ significantly from those for lowland reservoirs, which primarily serve to retain water for industrial and agricultural needs in the area, with an additional flood protection function. The aim of this study was to assess the factors determining the supply of lowland reservoirs using the example of the Pakoski Reservoir (Central–Western Poland) and to propose actions that would allow more efficient management of water resources in the catchment and reservoir, enabling the preservation of the current morphometric parameters in the face of climate change, adverse environmental phenomena, and increased anthropogenic pressure in the catchment area. This study focused on the Pakoski Reservoir, located in the southern part of the Kuyavian–Pomeranian Voivodeship. It was constructed fifty years ago as a result of damming water in the river systems of the Noteć and Mała Noteć Rivers. For decades, it served its functions, and its management posed no major issues. However, over the past decade, due to environmental changes and human activities in the catchment area, the reservoir has increasingly faced problems with filling. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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18 pages, 9075 KiB

Open AccessArticle

Intelligent Methods for Estimating the Flood Susceptibility in the Danube Delta, Romania

by Romulus Costache, Anca Crăciun, Nicu Ciobotaru and Alina Bărbulescu

Water 2024, 16(23), 3511; https://doi.org/10.3390/w16233511 - 6 Dec 2024

Cited by 1 | Viewed by 939

Abstract

Floods, along with other natural and anthropogenic disasters, profoundly disrupt both society and the environment. Populations residing in deltaic regions worldwide are particularly vulnerable to these threats. A prime example is the Danube Delta (DD), located in the Romanian sector of the Black Sea. This research paper aims to identify areas within the DD that are highly or very highly susceptible to flooding. To accomplish this, we employed a combination of multicriteria decision-making (AHP) and artificial intelligence (AI) techniques, including deep learning neural networks (DLNNs), support vector machines (SVMs), and multilayer perceptron (MLP). The input data comprised previously flooded regions alongside eight geographical factors. All models identified high or very high flood potential of over 65% of the studied area. The models’ performance was assessed using receiver operating characteristic (ROC) analysis, demonstrating excellent outcomes evaluated by the area under the curve (AUC) exceeding 0.908. This study is significant as it lays the groundwork for implementing measures against flood impacts in the DD. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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21 pages, 2910 KiB

Open AccessArticle

Streamflow Prediction with Time-Lag-Informed Random Forest and Its Performance Compared to SWAT in Diverse Catchments

by Desalew Meseret Moges, Holger Virro, Alexander Kmoch, Raj Cibin, Rohith A. N. Rohith, Alberto Martínez-Salvador, Carmelo Conesa-García and Evelyn Uuemaa

Water 2024, 16(19), 2805; https://doi.org/10.3390/w16192805 - 2 Oct 2024

Cited by 3 | Viewed by 2121

Abstract

This study introduces a time-lag-informed Random Forest (RF) framework for streamflow time-series prediction across diverse catchments and compares its results against SWAT predictions. We found strong evidence of RF’s better performance by adding historical flows and time-lags for meteorological values over using only actual meteorological values. On a daily scale, RF demonstrated robust performance (Nash–Sutcliffe efficiency [NSE] > 0.5), whereas SWAT generally yielded unsatisfactory results (NSE < 0.5) and tended to overestimate daily streamflow by up to 27% (PBIAS). However, SWAT provided better monthly predictions, particularly in catchments with irregular flow patterns. Although both models faced challenges in predicting peak flows in snow-influenced catchments, RF outperformed SWAT in an arid catchment. RF also exhibited a notable advantage over SWAT in terms of computational efficiency. Overall, RF is a good choice for daily predictions with limited data, whereas SWAT is preferable for monthly predictions and understanding hydrological processes in depth. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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24 pages, 11092 KiB

Open AccessFeature PaperArticle

Influence of Marine Currents, Waves, and Shipping Traffic on Sulina Channel Fairway at the Mouth of the Black Sea

by Mihai Valentin Stancu, Maria Ilinca Cheveresan, Daniela Sârbu, Adrian Maizel, Romeo Soare, Alina Bărbulescu and Cristian Ștefan Dumitriu

Water 2024, 16(19), 2779; https://doi.org/10.3390/w16192779 - 29 Sep 2024

Cited by 1 | Viewed by 1866

Abstract

This study comprehensively explores the intricate hydrodynamic and geomorphological processes that affect the Sulina Channel and bar area. It employs advanced hydrodynamic, wave, and sediment transport models to simulate the influence of marine currents, waves, and shipping traffic on sediment transport and deposition patterns, providing valuable insights for maintaining navigable conditions in the Sulina Channel. It is shown that sediment deposition is highly dynamic, particularly in the Sulina bar area, where rapid sediment recolonization occurs within one to two months after dredging. The simulation indicates that vessels with drafts of 11.5 m cause notable erosion. In comparison, drafts of 7 m have a minimal impact on sediment transport, emphasizing the importance of managing vessel drafts to mitigate sediment disturbances. This research highlights and quantifies the siltation phenomenon from the Black Sea to the mouth of the Sulina Channel, effectively addressing the challenges posed by natural and anthropogenic factors to ensure the Channel’s sustainability and operational efficiency. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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15 pages, 2953 KiB

Open AccessArticle

Characteristics of Runoff Changes during the Freeze–Thaw Period and the Response to Environmental Changes in a High-Latitude Water Tower

by Moran Xu, Yongming Chen, Dongmei Liu, Peng Qi, Yingna Sun, Licheng Guo and Guangxin Zhang

Water 2024, 16(19), 2735; https://doi.org/10.3390/w16192735 - 26 Sep 2024

Viewed by 893

Abstract

Runoff in high-latitude water towers is crucial for ecological and human water demands during freeze–thaw periods but is highly sensitive to climate change and human activities. This study focuses on Changbai Mountain, the source of the Songhua, Tumen, and Yalu rivers, analyzing runoff variation and its environmental responses using the modified Mann–Kendall method and the water–energy balance equation. The results show significant non-stationarity in runoff trends, with an increasing trend in the Yalu River basin (p < 0.05), a decreasing trend in the Tumen River basin (p < 0.05), and complex trends in the Songhua River basin. Additionally, the relationship between runoff and driving factors during freeze–thaw periods was quantized. When the snowfall, potential evapotranspiration (E0), and subsurface changes increased by 1%, the snowmelt runoff changes were 1.58~1.96%, −0.58~−1.96%, and −0.86~−1.11% in the Yalu River basin; 2.16~2.35%, −1.04~−1.35%, and −1.56~−1.95% in the Tumen River basin; and 1.44~2.41%, −0.44~−1.41%, and −0.72~−1.62% in the Songhua River basin. The increased snowfall was the most prominent reason for the increase in snowmelt runoff during spring. The results of this study will benefit ecosystem conservation and the stability of downstream water supply in this high-latitude water tower. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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19 pages, 4301 KiB

Open AccessArticle

The Necessity of Updating IDF Curves for the Sharjah Emirate, UAE: A Comparative Analysis of 2020 IDF Values in Light of Recent Urban Flooding (April 2024)

by Khalid B. Almheiri, Rabee Rustum, Grant Wright and Adebayo J. Adeloye

Water 2024, 16(18), 2621; https://doi.org/10.3390/w16182621 - 15 Sep 2024

Cited by 1 | Viewed by 2400

Abstract

In the arid Arabian Peninsula, particularly within the United Arab Emirates (UAE), the perception of rainfall has shifted from a natural blessing to a significant challenge for infrastructure and community resilience. The unprecedented storm on 17 April 2024, exposed critical vulnerabilities in the UAE’s urban infrastructure and flood management practices, revealing substantial gaps in handling accumulated precipitation. This study addresses the necessity of updating the Intensity–Duration–Frequency (IDF) curves for the Sharjah Emirate by utilizing recent precipitation data from 2021 to April 2024, alongside previously published 2020 data. By recalibrating the IDF curves based on data from three meteorological stations, this study reveals a substantial increase in rainfall intensities across all durations and return periods. Rainfall intensities increased by an average of 36.76% in Sharjah, 26.52% in Al Dhaid, and 17.55% in Mleiha. These increases indicate a trend towards more severe and frequent rainfall events, emphasizing the urgent need to revise hydrological models and infrastructure designs to enhance flood resilience. This study contributes valuable insights for policymakers, urban planners, and disaster management authorities in the UAE and similar regions worldwide. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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28 pages, 10454 KiB

Open AccessArticle

Hydrological Monitoring System of the Navío-Quebrado Coastal Lagoon (Colombia): A Very Low-Cost, High-Value, Replicable, Semi-Participatory Solution with Preliminary Results

by Andrea Gianni Cristoforo Nardini, Jairo R. Escobar Villanueva and Jhonny I. Pérez-Montiel

Water 2024, 16(16), 2248; https://doi.org/10.3390/w16162248 - 9 Aug 2024

Cited by 1 | Viewed by 1629

Abstract

Like many coastal lagoons in several countries, the “Navío Quebrado” lagoon (La Guajira, Colombia) is a very delicate and precious environment; indeed, it is a nationally recognized Flora and Fauna Sanctuary. Several factors, including climate change, are threatening its existence because of changes in the governing hydro-morphological and biological processes. Certainly, the first step to addressing this problem is to understand its hydrological behavior and to be able to replicate, via simulation, its recent history before inferring likely futures. These potential futures will be marked by changes in the water input by its tributary, the Camarones River, and by modified water exchange with the sea, according to a foreseen sea level rise pattern, as well as by a different evaporation rate from the free surface, according to temperature changes. In order to achieve the required ability to simulate future scenarios, data on the actual behavior have to be gathered, i.e., a monitoring system has to be set up, which to date is non-existent. Conceptually, designing a suitable monitoring system is not a complex issue and seems easy to implement. However, the environmental, socio-cultural, and socio-economic context makes every little step a hard climb. An extremely simple—almost “primitive”—monitoring system has been set up in this case, which is based on very basic measurements of river flow velocity and water levels (river, lagoon, and sea) and the direct participation of local stakeholders, the most important of which is the National Park unit of the Sanctuary. All this may clash with the latest groovy advances of science, such as in situ automatized sensors, remote sensing, machine learning, and digital twins, and several improvements are certainly possible and desirable. However, it has a strong positive point: it provides surprisingly reasonable data and operates at almost zero additional cost. Several technical difficulties made this exercise interesting and worthy of being shared. Its novelty lies in showing how old, simple methods may offer a working solution to new challenges. This humble experience may be of help in several other similar situations across the world. Full article

(This article belongs to the Special Issue Climate Change and Hydrological Processes)

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