Felipe Fileni, Hayley Fowler, Elizabeth Lewis, Fiona McLay, Longzhi Yang
Abstract The absence of an accessible and quality-assured national flow dataset is a limiting factor in sub-daily hydrological modelling in Great Britain. The recent development of measuring authority APIs and projects such as the Floods and Droughts Research Infrastructure (FDRI) programme aim to facilitate access to such data. Basic quality-control (QC) of 15-minute data is performed by the data collection authorities and the National River Flow Archive (NRFA). Still, there is a need for a comprehensible and verifiable quality control methodology. This paper presents an initial assessment of the available data and examines what needs to be done for applicability of the data at national scale. The 15-minute flow series has many inconsistencies, and there are also inconsistencies with the NRFA Annual Maximum values. When producing a QCed dataset, decisions regarding the retention of data values need to be taken and recorded. Furthermore, QC should remove and rectify erroneous values, such as negative and above world record flows; and an assessment of homogeneity and truncated values in the stations could be beneficial to flag suspect data. The complex chain for production and changeability of flow and level data makes data curation and governance imperative to assure the longevity of the dataset.
{"title":"A quality-control framework for sub-daily flow and level data for hydrological modelling in Great Britain","authors":"Felipe Fileni, Hayley Fowler, Elizabeth Lewis, Fiona McLay, Longzhi Yang","doi":"10.2166/nh.2023.045","DOIUrl":"https://doi.org/10.2166/nh.2023.045","url":null,"abstract":"Abstract The absence of an accessible and quality-assured national flow dataset is a limiting factor in sub-daily hydrological modelling in Great Britain. The recent development of measuring authority APIs and projects such as the Floods and Droughts Research Infrastructure (FDRI) programme aim to facilitate access to such data. Basic quality-control (QC) of 15-minute data is performed by the data collection authorities and the National River Flow Archive (NRFA). Still, there is a need for a comprehensible and verifiable quality control methodology. This paper presents an initial assessment of the available data and examines what needs to be done for applicability of the data at national scale. The 15-minute flow series has many inconsistencies, and there are also inconsistencies with the NRFA Annual Maximum values. When producing a QCed dataset, decisions regarding the retention of data values need to be taken and recorded. Furthermore, QC should remove and rectify erroneous values, such as negative and above world record flows; and an assessment of homogeneity and truncated values in the stations could be beneficial to flag suspect data. The complex chain for production and changeability of flow and level data makes data curation and governance imperative to assure the longevity of the dataset.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135918252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This study examines the relationship between relative vorticity, a key variable in mid-latitude synoptic motions, and precipitation in Iran. Using the S-mode PCA, activity centers of relative vorticity and precipitation were identified. Canonical correlation analysis (CCA) was applied to the factor scores of these centers to reveal coupled patterns of relative vorticity and precipitation. The analysis is based on 500- and 850-hPa relative vorticity fields at 2.5° grid points (10°–70° E and 10°–70° N) and uses monthly relative vorticity values from NCEP-DOE reanalysis databases (1981–2020) along with standardized rainfall data from 97 Iranian synoptic stations. Three main CCA patterns reveal connections: 500-hPa relative vorticity changes in the eastern Mediterranean, Middle East, and Iran relate to eastern Iran's precipitation. Relative vorticity over Eastern Europe inversely correlates with southern Caspian Sea coast precipitation. Changes over Turkey and Cyprus can affect northwestern Iran's rainfall. The changes in 850-hPa relative vorticity over the Arabian Sea inversely link to eastern Iran's precipitation, while those over the eastern Mediterranean directly connect to western Iran's precipitation. Relative vorticity changes in Eastern Europe negatively correlate with southwestern Caspian Sea coast precipitation.
{"title":"The relationship between the large-scale relative vorticity fields and precipitation over Iran","authors":"Azita Amiri, Bohloul Alijani, Ebrahim Fattahi, Maral Habibi","doi":"10.2166/nh.2023.301","DOIUrl":"https://doi.org/10.2166/nh.2023.301","url":null,"abstract":"Abstract This study examines the relationship between relative vorticity, a key variable in mid-latitude synoptic motions, and precipitation in Iran. Using the S-mode PCA, activity centers of relative vorticity and precipitation were identified. Canonical correlation analysis (CCA) was applied to the factor scores of these centers to reveal coupled patterns of relative vorticity and precipitation. The analysis is based on 500- and 850-hPa relative vorticity fields at 2.5° grid points (10°–70° E and 10°–70° N) and uses monthly relative vorticity values from NCEP-DOE reanalysis databases (1981–2020) along with standardized rainfall data from 97 Iranian synoptic stations. Three main CCA patterns reveal connections: 500-hPa relative vorticity changes in the eastern Mediterranean, Middle East, and Iran relate to eastern Iran's precipitation. Relative vorticity over Eastern Europe inversely correlates with southern Caspian Sea coast precipitation. Changes over Turkey and Cyprus can affect northwestern Iran's rainfall. The changes in 850-hPa relative vorticity over the Arabian Sea inversely link to eastern Iran's precipitation, while those over the eastern Mediterranean directly connect to western Iran's precipitation. Relative vorticity changes in Eastern Europe negatively correlate with southwestern Caspian Sea coast precipitation.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"294 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135968022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract In Canada's Northwest Territories (NT), industrial activities conducted during the winter, such as ice road construction and exploratory drilling, require the use of water from ice-covered water bodies. Withdrawal in excess of 10% of available under-ice volume can threaten fish habitat or other users. The Land and Water Boards (LWBs) of the Mackenzie Valley require water licences for water withdrawal beyond regulated thresholds. Applicants must provide information including identification and location of proposed water sources, timing and proposed volume of water and winter water withdrawal must be limited to <10% of available volume to protect fish habitat under the ice. Many applicants are at early project stages and the necessary information on bathymetry and volumes of water is not readily available or requires expertise and effort that may not be feasible at the early stages of smaller projects. This paper describes the alternative method for determining available winter water volumes from lakes to support small-scale projects. A simple formula of ‘allowable volume (m3) = surface area (m2) * 0.1 m’ was developed and tested to provide a conservative estimate of under-ice volumes from easily available data which is protective in spite of uncertainties inherent in limited data.
{"title":"Alternative method for determining available winter water volumes from lakes to support small-scale projects","authors":"Rick Walbourne, Sarah Elsasser, Neil Hutchinson","doi":"10.2166/nh.2023.032","DOIUrl":"https://doi.org/10.2166/nh.2023.032","url":null,"abstract":"Abstract In Canada's Northwest Territories (NT), industrial activities conducted during the winter, such as ice road construction and exploratory drilling, require the use of water from ice-covered water bodies. Withdrawal in excess of 10% of available under-ice volume can threaten fish habitat or other users. The Land and Water Boards (LWBs) of the Mackenzie Valley require water licences for water withdrawal beyond regulated thresholds. Applicants must provide information including identification and location of proposed water sources, timing and proposed volume of water and winter water withdrawal must be limited to &lt;10% of available volume to protect fish habitat under the ice. Many applicants are at early project stages and the necessary information on bathymetry and volumes of water is not readily available or requires expertise and effort that may not be feasible at the early stages of smaller projects. This paper describes the alternative method for determining available winter water volumes from lakes to support small-scale projects. A simple formula of ‘allowable volume (m3) = surface area (m2) * 0.1 m’ was developed and tested to provide a conservative estimate of under-ice volumes from easily available data which is protective in spite of uncertainties inherent in limited data.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136013490","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract This study was conducted to identify and map the surface irrigation potential in the data-scarce Jewuha watershed of the Awash Basin, Ethiopia. The suitability of the land, based on the soil characteristics and slope, was first assessed by the parametric evaluation technique. The overall suitability of the land was then evaluated considering additional factors including land use land cover, proximity to a water source and road using weighted overlay analysis through the analytic hierarchical process (AHP). Water diversion sites as the source of water supply points were selected based on theoretical site selection criteria with the help of a geographic information system (GIS) and physical observation. The surface water available at the diversion sites was estimated using the Soil and Water Assessment Tool (SWAT) model combined with the spatial proximity regionalization technique. The land suitability analysis revealed that 16.7% (11,359 ha) of the study area is suitable for surface irrigation. Five diversion sites were identified as sources of water supply and the total flows at these sites were 12.92 Mm3. It was found that only 27.3% (3,098 ha) of the suitable land, 5% of the total area of the watershed, can be effectively developed by surface irrigation.
{"title":"Identification and mapping of surface irrigation potential in the data-scarce Jewuha watershed, Middle Awash River Basin, Ethiopia","authors":"Manamno Beza Dinku, Habtamu Hailu Kebede","doi":"10.2166/nh.2023.082","DOIUrl":"https://doi.org/10.2166/nh.2023.082","url":null,"abstract":"Abstract This study was conducted to identify and map the surface irrigation potential in the data-scarce Jewuha watershed of the Awash Basin, Ethiopia. The suitability of the land, based on the soil characteristics and slope, was first assessed by the parametric evaluation technique. The overall suitability of the land was then evaluated considering additional factors including land use land cover, proximity to a water source and road using weighted overlay analysis through the analytic hierarchical process (AHP). Water diversion sites as the source of water supply points were selected based on theoretical site selection criteria with the help of a geographic information system (GIS) and physical observation. The surface water available at the diversion sites was estimated using the Soil and Water Assessment Tool (SWAT) model combined with the spatial proximity regionalization technique. The land suitability analysis revealed that 16.7% (11,359 ha) of the study area is suitable for surface irrigation. Five diversion sites were identified as sources of water supply and the total flows at these sites were 12.92 Mm3. It was found that only 27.3% (3,098 ha) of the suitable land, 5% of the total area of the watershed, can be effectively developed by surface irrigation.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136012541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hongwu Tang, Yang Yu, Saiyu Yuan, Zhipeng Li, Hao Cao, Chenyu Jiang, Carlo Gualtieri
Abstract The ecology of the aquatic environment in Poyang Lake, the largest fresh lake in China, is notably impacted by the backflow from the Yangtze River, which conveys a high flux of sediments. This study employs a widely recognized numerical model to replicate the backflow in 2007 (the strongest backflow after the operation initiation of the Three Gorges Dam) to investigate the contributions of wind and backflow to the sediment transport process. The results show that the influences of wind and backflow on flow patterns and sediment transport processes have significant spatial heterogeneity. In the narrow waterway leading to the central lake area, hydrodynamics is mainly driven by backflow. Conversely, the hydrodynamics of the open expanse of the lake is primarily influenced by wind forces. Dominant wind leads to the formation of gyres, which significantly alter flow paths and push sediment into the upstream areas. As a result, the suspended sediment area expands at an average rate of 20.1–21.3 km2 daily, marking a 75–85% surge compared to the no wind condition (11.5 km2). The study facilitates a deeper understanding of sediment transport processes in large lakes.
{"title":"Hydrodynamics and sediment transport in Poyang Lake under the effects of wind and backflow","authors":"Hongwu Tang, Yang Yu, Saiyu Yuan, Zhipeng Li, Hao Cao, Chenyu Jiang, Carlo Gualtieri","doi":"10.2166/nh.2023.191","DOIUrl":"https://doi.org/10.2166/nh.2023.191","url":null,"abstract":"Abstract The ecology of the aquatic environment in Poyang Lake, the largest fresh lake in China, is notably impacted by the backflow from the Yangtze River, which conveys a high flux of sediments. This study employs a widely recognized numerical model to replicate the backflow in 2007 (the strongest backflow after the operation initiation of the Three Gorges Dam) to investigate the contributions of wind and backflow to the sediment transport process. The results show that the influences of wind and backflow on flow patterns and sediment transport processes have significant spatial heterogeneity. In the narrow waterway leading to the central lake area, hydrodynamics is mainly driven by backflow. Conversely, the hydrodynamics of the open expanse of the lake is primarily influenced by wind forces. Dominant wind leads to the formation of gyres, which significantly alter flow paths and push sediment into the upstream areas. As a result, the suspended sediment area expands at an average rate of 20.1–21.3 km2 daily, marking a 75–85% surge compared to the no wind condition (11.5 km2). The study facilitates a deeper understanding of sediment transport processes in large lakes.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136208574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jason Duguay, Karl-Erich Lindenschmidt, Mélanie Trudel, Antoine Pruneau
Abstract Collecting data on the dynamic breakup of a river's ice cover is a notoriously difficult task. However, such data are necessary to reconstruct the events leading to the formation of ice jams and calibrate numerical ice jam models. Photogrammetry using images from remotely piloted aircraft (RPA) is a cost-effective and rapid technique to produce large-scale orthomosaics and digital elevation maps (DEMs) of an ice jam. Herein, we apply RPA photogrammetry to document an ice jam that formed on a river in southern Quebec in the winter of 2022. Composite orthomosaics of the 2-km ice jam provided evidence of overbanking flow, hinge cracks near the banks and lengthy longitudinal stress cracks in the ice jam caused by sagging as the flow abated. DEMs helped identify zones where the ice rubble was grounded to the bed, thus allowing ice jam thickness estimates to be made in these locations. The datasets were then used to calibrate a one-dimensional numerical model of the ice jam. The model will be used in subsequent work to assess the risk of ice interacting with the superstructure of a low-level bridge in the reach and assess the likelihood of ice jam flooding of nearby residences.
{"title":"Aerial photogrammetry to characterise and numerically model an ice jam model in Southern Quebec","authors":"Jason Duguay, Karl-Erich Lindenschmidt, Mélanie Trudel, Antoine Pruneau","doi":"10.2166/nh.2023.010","DOIUrl":"https://doi.org/10.2166/nh.2023.010","url":null,"abstract":"Abstract Collecting data on the dynamic breakup of a river's ice cover is a notoriously difficult task. However, such data are necessary to reconstruct the events leading to the formation of ice jams and calibrate numerical ice jam models. Photogrammetry using images from remotely piloted aircraft (RPA) is a cost-effective and rapid technique to produce large-scale orthomosaics and digital elevation maps (DEMs) of an ice jam. Herein, we apply RPA photogrammetry to document an ice jam that formed on a river in southern Quebec in the winter of 2022. Composite orthomosaics of the 2-km ice jam provided evidence of overbanking flow, hinge cracks near the banks and lengthy longitudinal stress cracks in the ice jam caused by sagging as the flow abated. DEMs helped identify zones where the ice rubble was grounded to the bed, thus allowing ice jam thickness estimates to be made in these locations. The datasets were then used to calibrate a one-dimensional numerical model of the ice jam. The model will be used in subsequent work to assess the risk of ice interacting with the superstructure of a low-level bridge in the reach and assess the likelihood of ice jam flooding of nearby residences.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"106 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136294891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Vegetation flow is more and more widely studied by scholars at home and abroad because it is an important condition affecting river water quality. However, most of the studies were carried out based on the data of indoor experimental flumes, because the vegetation conditions in nature are more complex. The analytical solution of the flow velocity based on indoor conditions often has some problems when applied to practical projects. Therefore, we propose a numerical method based on the lattice Boltzmann method to simulate the vertical velocity distribution in an open channel with double-layered rigid vegetation. This method has high simulation accuracy in different vegetation conditions. At the same time, because the lattice Boltzmann method is more conducive to simulating complex boundary conditions, it is easier to combine with a multi-layered rigid vegetation flow and a flexible vegetation flow in nature after improvement, providing a basis for the application of indoor theoretical results to the outdoor.
{"title":"A numerical model to simulate the vertical velocity distribution in an open channel with double-layered rigid vegetation","authors":"Weidong Xuan, Yu Bai","doi":"10.2166/nh.2023.049","DOIUrl":"https://doi.org/10.2166/nh.2023.049","url":null,"abstract":"Abstract Vegetation flow is more and more widely studied by scholars at home and abroad because it is an important condition affecting river water quality. However, most of the studies were carried out based on the data of indoor experimental flumes, because the vegetation conditions in nature are more complex. The analytical solution of the flow velocity based on indoor conditions often has some problems when applied to practical projects. Therefore, we propose a numerical method based on the lattice Boltzmann method to simulate the vertical velocity distribution in an open channel with double-layered rigid vegetation. This method has high simulation accuracy in different vegetation conditions. At the same time, because the lattice Boltzmann method is more conducive to simulating complex boundary conditions, it is easier to combine with a multi-layered rigid vegetation flow and a flexible vegetation flow in nature after improvement, providing a basis for the application of indoor theoretical results to the outdoor.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135093749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Ecological flow is a restrictive condition set for human water consumption in water resources management to protect river ecosystems. However, uncertainties in hydrological conditions, changes in regulatory capacity, and temporal-spatial differences bring difficulties to the implementation and supervision of ecological flows. By analyzing the relevant concept and connotation of ecological flow, it is concluded that the ecological flow regimes suitable for practical application should be a dynamic interval rather than a fixed value. Therefore, an improved ecological flow calculation method was proposed, which is to increase the feasible lifting volume for different ecological service objects based on the determined ecological baseflow. Taking two cross-sections of the Weihe River as an example, the ecological flow was calculated by comprehensively considering the factors of inflow, fish survival, landscape, and agricultural irrigation. The result shows the lifting volume occurred in the high flow season (April–June), and the maximum ecological flow of LJC and WJB cross-sections was 20.2 and 16.0 m3/s, respectively. Moreover, it is a generalized approach that can be extended to a more complicated river system, and the calculation results have reliability and adaptability in integrated water regulation.
{"title":"Adaptive calculation of river ecological flow considering the variable lifting volume under changing conditions","authors":"Dandan Liu, Jiancang Xie, Ganggang Zuo, Jichao Liang","doi":"10.2166/nh.2023.187","DOIUrl":"https://doi.org/10.2166/nh.2023.187","url":null,"abstract":"Abstract Ecological flow is a restrictive condition set for human water consumption in water resources management to protect river ecosystems. However, uncertainties in hydrological conditions, changes in regulatory capacity, and temporal-spatial differences bring difficulties to the implementation and supervision of ecological flows. By analyzing the relevant concept and connotation of ecological flow, it is concluded that the ecological flow regimes suitable for practical application should be a dynamic interval rather than a fixed value. Therefore, an improved ecological flow calculation method was proposed, which is to increase the feasible lifting volume for different ecological service objects based on the determined ecological baseflow. Taking two cross-sections of the Weihe River as an example, the ecological flow was calculated by comprehensively considering the factors of inflow, fish survival, landscape, and agricultural irrigation. The result shows the lifting volume occurred in the high flow season (April–June), and the maximum ecological flow of LJC and WJB cross-sections was 20.2 and 16.0 m3/s, respectively. Moreover, it is a generalized approach that can be extended to a more complicated river system, and the calculation results have reliability and adaptability in integrated water regulation.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136344089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract To prepare measures to respond to climate-induced extreme droughts, consideration of various weather conditions is necessary. This study tried to generate extreme drought weather data using the Weather Research and Forecasting (WRF) model and apply it to the Long Short-Term Memory (LSTM), a deep learning artificial intelligence model, to produce the runoff instead of using conventional rainfall–runoff models. Finally, the standardized streamflow index (SSFI), the hydrological drought index, was calculated using the generated runoff to predict extreme droughts. As a result, the sensitivity test of meteorological data to runoff showed that using similar types of meteorological data could not improve runoff simulations with a maximum difference of 0.02 in Nash–Sutcliffe efficiency. During the drought year of 2015, the runoff generated by WRF and LSTM exhibited reduced monthly runoffs and more severe SSFI values below −2 compared to the observed data. This shows the significance of WRF-generated meteorological data in simulating potential extreme droughts based on possible physical atmospheric conditions using numerical representations. Furthermore, LSTM can simulate runoff without requiring specific physical data of the target catchment; therefore, it can simulate runoff in any catchment, including those in developing countries with limited data.
{"title":"Estimation of possible extreme droughts for a dam catchment in Korea using a regional-scale weather model and long short-term memory network","authors":"Mun-Ju Shin, Yong Jung","doi":"10.2166/nh.2023.192","DOIUrl":"https://doi.org/10.2166/nh.2023.192","url":null,"abstract":"Abstract To prepare measures to respond to climate-induced extreme droughts, consideration of various weather conditions is necessary. This study tried to generate extreme drought weather data using the Weather Research and Forecasting (WRF) model and apply it to the Long Short-Term Memory (LSTM), a deep learning artificial intelligence model, to produce the runoff instead of using conventional rainfall–runoff models. Finally, the standardized streamflow index (SSFI), the hydrological drought index, was calculated using the generated runoff to predict extreme droughts. As a result, the sensitivity test of meteorological data to runoff showed that using similar types of meteorological data could not improve runoff simulations with a maximum difference of 0.02 in Nash–Sutcliffe efficiency. During the drought year of 2015, the runoff generated by WRF and LSTM exhibited reduced monthly runoffs and more severe SSFI values below −2 compared to the observed data. This shows the significance of WRF-generated meteorological data in simulating potential extreme droughts based on possible physical atmospheric conditions using numerical representations. Furthermore, LSTM can simulate runoff without requiring specific physical data of the target catchment; therefore, it can simulate runoff in any catchment, including those in developing countries with limited data.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135246208","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract Due to global warming, extreme hydroclimatic events (e.g., floods) are expected to happen more frequently and last longer. This study investigated such an extreme flood in the transboundary Teesta River that occurred in October 2021. We attempted to quantify the event's impact using data from time series flood levels, precipitation-related satellite images, and two-dimensional hydromorphological modeling. We found it challenging for people to cope with such a hazardous event since the depth of the flooding increased 6.98-fold in just 24 h. Our simulation results indicate that a sand-filled sediment measuring 0.27 m thick covered more than 33% cropland, and the velocity increased by almost 2.5 times. 136,000 individuals were marooned in the water. Compared to previous flooding events in its basin, which occurred in India and Bangladesh, the river appears to have some natural shock absorption features, i.e., a wide braided plain. We propose impact-based forecasting with a proactive early response as a valuable tool for managing such extreme events.
{"title":"Evaluating 2021 extreme flash flood of Teesta River","authors":"None Shampa, Israt Jahan Nejhum, Md. Manjurul Hussain, Mohammad Muddassir Islam, Rubaid Hassan Zoha","doi":"10.2166/nh.2023.122","DOIUrl":"https://doi.org/10.2166/nh.2023.122","url":null,"abstract":"Abstract Due to global warming, extreme hydroclimatic events (e.g., floods) are expected to happen more frequently and last longer. This study investigated such an extreme flood in the transboundary Teesta River that occurred in October 2021. We attempted to quantify the event's impact using data from time series flood levels, precipitation-related satellite images, and two-dimensional hydromorphological modeling. We found it challenging for people to cope with such a hazardous event since the depth of the flooding increased 6.98-fold in just 24 h. Our simulation results indicate that a sand-filled sediment measuring 0.27 m thick covered more than 33% cropland, and the velocity increased by almost 2.5 times. 136,000 individuals were marooned in the water. Compared to previous flooding events in its basin, which occurred in India and Bangladesh, the river appears to have some natural shock absorption features, i.e., a wide braided plain. We propose impact-based forecasting with a proactive early response as a valuable tool for managing such extreme events.","PeriodicalId":13096,"journal":{"name":"Hydrology Research","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135193314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}