Journal of Hydrology最新文献

{"title":"Improvement of rootzone soil moisture estimation over the Tibetan Plateau based on the exponential filter model and Copernicus Climate Change Service (C3S) surface observations","authors":"Yuxi Song ,&nbsp;Jianbin Su ,&nbsp;Tinghua Mou ,&nbsp;Jun Wen ,&nbsp;Gaofeng Zhu ,&nbsp;Xiaojing Wu ,&nbsp;Donghai Zheng","doi":"10.1016/j.jhydrol.2025.133882","DOIUrl":"10.1016/j.jhydrol.2025.133882","url":null,"abstract":"<div><div>This study is the first attempt to assess and enhance the applicability of exponential filter (ExpF) model to estimate rootzone soil moisture (RZSM) across different climatic and land conditions over the Tibetan Plateau (TP). To this end, in situ soil moisture (SM) profile data collected from five regional-scale monitoring networks are firstly used for the model assessment at local scale. Then a random forest (RF) approach is adopted to regionalize the critical model parameter (i.e. characteristic time length <span><math><mrow><mi>T</mi></mrow></math></span>) to enhance the estimation of RZSM at plateau scale using satellite-based surface SM (SSM) data from the Copernicus Climate Change Service (C3S). Results indicate that with increasing soil depth, the application accuracy of the ExpF model decreases due to weakened coupling strength between the SSM and RZSM, while the <em>T</em> values and their spatial heterogeneity increase due to greater variability in hydraulic connectivity between the SSM and RZSM across different monitoring sites. From the arid west TP to the semi-arid and humid east TP, the application accuracy of the ExpF model increases, while the variability in model accuracy across different monitoring sites shows a decreasing trend. The spatial distribution of regionalized <em>T</em> values at shallower depth is opposite to that of sand content, with higher values in the northwest TP and lower values in the Qaidam basin and central TP. For the deeper depth, higher values are also noted in the southeast TP due to the increasingly significant impact of meteorological and vegetation factors. The RZSM estimations based on the ExpF model with the regionalized <em>T</em> values capture better the observed dynamics and largely resolve the deficiencies noted for the C3S-based RZSM product. Above findings confirm the applicability of the ExpF model on the TP, offering valuable insights into enhancing the accuracy of RZSM estimations based on the satellite-based SSM products.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133882"},"PeriodicalIF":5.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144669994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the propagation characteristics of meteorological drought to hydrological drought using a three-dimensional method","authors":"Xiaoli Yang,&nbsp;Lingfeng Xie,&nbsp;Ding Luo,&nbsp;Zhoubing Ye","doi":"10.1016/j.jhydrol.2025.133930","DOIUrl":"10.1016/j.jhydrol.2025.133930","url":null,"abstract":"<div><div>In the context of global warming, extreme drought events have become increasingly frequent, resulting in serious losses to industrial and agricultural production. To address drought risks and mitigate substantial impacts, it is essential to study the changes in drought characteristics under climate change. However, traditional drought identification methods based on grid data are inadequate to capture the developmental characteristics of drought events. Therefore, we need to adopt a three-dimensional (3D) drought identification method to describe the evolution of drought events. We improved the existing 3D drought identification and matching processes and constructed a Drought Characteristic Propagation Index (DCPI), by comparing the drought characteristics between historical and future periods. This allowed us to compare the drought propagation characteristics in the Yellow River Basin across historical and future periods and discuss their robustness. Results indicate that: (1) The improved 3D drought identification method can solve the drought identification continuity problem of 25.3% meteorological drought and 39.8% hydrological drought respectively. (2) The meteorological drought in the SSP370 scenario is most likely to cause hydrological drought based on the multi-model ensemble. In the future, drought will show an intensifying trend. The intensity conversion efficiency of drought in the future will increase by 64.3%, and the area conversion efficiency will increase by 54.2%, which are higher than those in the historical period. (3) There are some differences between the results of multi-model set and single model, but both show that drought propagation is enhanced compared with the historical period.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133930"},"PeriodicalIF":5.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144669993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-term carbon dioxide dynamics variability at submerged macrophyte habitat of a subtropical shallow lake","authors":"Lei Hong ,&nbsp;Cheng Hu ,&nbsp;Minliang Jiang ,&nbsp;Xuejing Shi ,&nbsp;Juhua Luo ,&nbsp;Qitao Xiao","doi":"10.1016/j.jhydrol.2025.133950","DOIUrl":"10.1016/j.jhydrol.2025.133950","url":null,"abstract":"<div><div>Submerged macrophytes are widespread and deemed fundamental components particularly in shallow lakes. They play a pivotal role by rendering essential ecosystem services, however, their roles in governing the carbon dioxide (CO₂) budget remain controversial and unclear, likely posing a significant challenge to the comprehensive understanding of CO₂ cycling within lake ecosystems. To fill the knowledge gaps, the dynamic variability of CO₂ within the submerged macrophytes habitats in a shallow subtropical lake located in eastern China was comprehensively investigated based on long-term (2005–2017) field measurements span different seasons. The findings revealed that the submerged macrophytes habitats were characterized by superior water quality, manifested as low nutrient loadings, reduced algal biomass, and heightened water clarity, when juxtaposed with open water regions of the lake devoid of macrophytes. The long-term measurements demonstrated that the submerged macrophytes habit functioned as relatively low CO₂ source, with an annual mean emissions flux of 13.55 ± 9.20 mmol m⁻² d⁻¹. The presence of macrophytes and good water quality (e.g. low nutrient loadings) likely contributed to low emissions within submerged macrophyte habitat via increasing CO₂ fixation and reducing CO₂ production, respectively. The temporal fluctuations in CO₂ emissions from submerged macrophyte habitats were closely associated with water clarity, which in turn highlighted the role of water quality in determining CO₂ variability within submerged macrophyte habitats. Furthermore, the long-term measurements uncovered significant inter-annual variations in the CO₂ emissions, highlighting the critical importance of long-term measurements to derive unbiased estimates of the CO₂ budgets within the submerged macrophyte habitats of inland lakes.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133950"},"PeriodicalIF":5.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144670049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Challenges in measuring the size and velocity of large raindrops: a comparison of selected methods","authors":"M. Beczek ,&nbsp;M. Neumann ,&nbsp;R. Mazur ,&nbsp;D. Zumr ,&nbsp;T. Dostal ,&nbsp;A. Bieganowski","doi":"10.1016/j.jhydrol.2025.133932","DOIUrl":"10.1016/j.jhydrol.2025.133932","url":null,"abstract":"<div><div>The characteristics of raindrops play a crucial role in various fields, including meteorology, hydrology, agriculture, horticulture, weather forecasting, and atmospheric physics. Among the various techniques and measurement devices for characterising precipitation drops, disdrometers are currently most commonly used and high-speed cameras are becoming more popular. A significant challenge can be the characterisation of large drops, associated with e.g. throughfall phenomenon or heavy convective rainstorms, which are susceptible to shape changes as a result of oscillations. Thus, the aim of the study was to evaluate the suitability of selected methods for measuring the size and velocity of large drops. The study was based on the formation of single drops with specified diameters (3.2, 4.3 and 5.3 mm) and different heights of release (1, 3 and 5 m). The performed analyses included a comparison of data obtained from two types of laser disdrometers (Thies Clima LPM and Parsivel²), single high-speed camera and a set of synchronised high-speed cameras with 3D PTV module (i.e. particle tracking velocimetry). The measurements were complemented by a characterisation of drop shape deformation that may have influenced the results, which was assessed using high-speed imaging technique. Study showed that high-speed cameras allowed a very accurate analysis of the parameters of large individual drops (i.e. size, velocity and shape descriptors) in contrast to the tested disdrometers which showed substantial variability in the results. The coefficient of variation for the measured parameters was up to 5.5 % for the cameras, and up to 13.6 % for the disdrometers. In this context, high-speed cameras provide an alternative for measuring processes that are subject to significant errors (e.g. related to the irregularity and variability of the drop shape) in disdrometer-based measurements, such as throughfall, and serve as a valuable tool for validating widely used instruments. What is more, the use of camera set combined with a PTV module provides a full 3D mapping of the trajectory of falling drop, allowing insight into the velocity components (the vertical component, Vy, and horizontal components, Vx and Vz) of individual drops, which could be important in the case of drops whose flight has been disturbed by wind.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133932"},"PeriodicalIF":5.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144669992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantification of the sinking conditions of large wood and maximum backwater rise at trash racks","authors":"Songli Yu,&nbsp;Yidan Ai,&nbsp;Mengyang Liu,&nbsp;Wenxin Huai","doi":"10.1016/j.jhydrol.2025.133929","DOIUrl":"10.1016/j.jhydrol.2025.133929","url":null,"abstract":"<div><div>The accumulation of large wood (LW) is a significant concern for river management. The sinking behavior of LW plays a crucial role in altering the shape and submerged volume of LW accumulation, which in turn changes the flow condition and poses a high risk to hydraulic structures. Through laboratory model tests, this work innovatively introduces the critical Froude number as an indicator for the initiation of sinking in a large wood row (LWR) with uniform density floating on the water surface. Factors such as increased LWR length, a higher diameter-to-flow depth ratio, and reduced LW density all lead to a higher critical Froude number. Based on these findings, a formula is proposed to estimate the critical Froude number, which is parameterized by the diameter, density, and length of LWR. Additionally, the sinking of LW simultaneously increases backwater rise and decreases incoming flow velocity, eventually halting further sinking, and giving rise to the maximum backwater rise under the condition of certain discharge. By modeling this special state, a prediction formula for maximum backwater rise is derived and analyzed. Overall, this study enhances the understanding of LW sinking dynamics and provides deep insights into LW management in rivers.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133929"},"PeriodicalIF":5.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144669956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatio-temporal heterogeneities in hydrologic dynamics across the Asian Water Tower","authors":"Saugat Aryal,&nbsp;Yadu Pokhrel","doi":"10.1016/j.jhydrol.2025.133951","DOIUrl":"10.1016/j.jhydrol.2025.133951","url":null,"abstract":"<div><div>This study presents a multi-decadal (1979–2018) analysis of hydrologic changes across the entire Asian Water Tower (AWT) region, using high-resolution hydrological-hydrodynamic modeling. We find significant spatiotemporal heterogeneity in hydrological trends across the AWT basins, characterized by diverse changes in river discharge, water storage, flood regimes, and terrestrial water storage (TWS) dynamics. Western basins such as the Amu Darya and Tarim show increasing flood risks (up to ∼60% increase in flood occurrence) and significant snow water equivalent (SWE) contributions to TWS (up to ∼41%), while central basins are transitioning to regions of increasing water scarcity with strong subsurface storage contribution evident in the Ganges (up to ∼79%). The dominance of subsurface storage reaches its peak in the eastern basins, where the Yangtze and Yellow River exhibit the highest proportions (∼78% and ∼83% respectively), with the Yangtze further distinguished by a notable river storage contribution (∼21%). In contrast, southeastern basins including the Mekong, Irrawaddy, and Salween present complex, temporally varying patterns that defy simple categorization. These findings highlight the complex interplay of surface and subsurface processes in the AWT, underscoring the need for basin-specific approaches in water resource management and climate change adaptation strategies.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133951"},"PeriodicalIF":5.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144669990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Convective dissolution in layered porous media with application to CO2 geological sequestration: Experimental and numerical insights into layering configuration and interface angle","authors":"Didi Li,&nbsp;Yizhen Chen,&nbsp;Suihong Chen","doi":"10.1016/j.jhydrol.2025.133952","DOIUrl":"10.1016/j.jhydrol.2025.133952","url":null,"abstract":"<div><div>Convective dissolution is crucial for the secure and permanent sequestration of CO₂ within deep saline aquifers. Despite the prevalence of inclined stratified formations at potential sequestration sites, there is a lack of systematic investigations about the combined effects of layering configurations and inclination angles on convective dissolution. This study endeavored to bridge this gap by conducting a series of laboratory experiments complemented by numerical simulations. The aim was to elucidate the impact of various inclination angles on convective mixing within diverse stratified structures. Our findings revealed that within stratified formations, phenomena such as finger accumulation and enhanced finger merging at decreasing-permeability interfaces co-occurred with typical fingering patterns in homogeneous media. Additionally, an amplified shielding effect was observed in increasing-permeability formations. Within our research scope, a more significant permeability contrast between layers was found to result in more pronounced variations in convective dissolution characteristics, without altering their inherent pattern. Inclined interfaces within stratified formations were found to further intensify the accumulation of leading fingers at decreasing-permeability interfaces and to facilitate penetration across increasing-permeability interfaces, with these effects being more pronounced at steeper angles. In our study, the average mass flux at interface was considerably higher in configurations with decreasing permeability, diminishing as the interface angle increased. These findings suggest that in practical carbon geological storage applications, employing layers with decreasing permeability and less steep interface angles, coupled with a higher permeability contrast between layers, could enhance the efficiency of dissolution sequestration within inclined stratified layers. This study provides critical insights into the optimization of carbon sequestration strategies within inclined, multi-layered saline aquifers, highlighting the importance of layer configuration and interface geometry in the convective dissolution process.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133952"},"PeriodicalIF":5.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144669959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Probability analysis of wet and dry encounters in the Yangtze and Yellow River basins under changing environmental conditions","authors":"Yuli Ruan ,&nbsp;Lijun Jin ,&nbsp;Jianyun Zhang ,&nbsp;Zhongrui Ning ,&nbsp;Guoqing Wang ,&nbsp;Cuishan Liu ,&nbsp;Zhenxin Bao ,&nbsp;Weiru Zhao ,&nbsp;Mingming Song","doi":"10.1016/j.jhydrol.2025.133953","DOIUrl":"10.1016/j.jhydrol.2025.133953","url":null,"abstract":"<div><div>Assessing the probability of dry-wet runoff encounters under changing environmental conditions provides critical scientific support for sustainable water resource management and watershed security. Therefore, this study enhances the Generalized Additive Model for Location, Scale, and Shape (GAMLSS) through variable reconstruction and error correction, thus proposing an innovative methodology for assessing high-low runoff encounter probabilities in the Yangtze and Yellow River Basins under changing environmental conditions. Atmospheric circulation pattern analysis is further integrated to elucidate mechanisms underlying concurrent low-flow events. Key findings reveal that: (1) The Log-Normal distribution exhibits superior goodness-of-fit for runoff frequency in the Yangtze River’s headwater (source) and downstream regions, while Gamma and Normal distributions emerge as optimal for the upper and middle reaches, respectively. The Inverse Gaussian and Reverse Gumbel distributions demonstrate enhanced performance in the Yellow River Basin. (2) The optimized GAMLSS achieves remarkable accuracy, with empirical–theoretical value deviations constrained between − 0.1 and 0.1, and Nash-Sutcliffe Efficiency (NSE) values ranging from 0.9756 to 0.9966 across basins. (3) Analysis of 1963–2022 data identifies the highest dry-dry encounter probability (23.48 %) in the upper reaches of both basins, followed by headwater (20.89 %) and middle reaches (18.35 %), with the lowest probability (15.37 %) observed in lower reaches. (4) While the Zhimenda-Tangnaihai, Yichang-Toudaoguai, and Datong-Huayuankou combinations show decreasing dry encounter probabilities, the Dajin-Lanzhou combination exhibits a statistically significant upward trend (p &lt; 0.05) in low-flow synchronicity. (5) Concurrent low-flow events in the Yangtze and Yellow Rivers are predominantly linked to two atmospheric circulation patterns: (a) the Lake Baikal high-pressure ridge, and (b) anomalous strengthening of the western Pacific subtropical high. This study advances hydrological extreme event prediction by integrating statistical modeling innovation with climatic mechanism analysis, providing critical insights for adaptive watershed management under global change scenarios.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133953"},"PeriodicalIF":5.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144670051","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trends and causal structures of rain-on-snow flooding","authors":"Nishant Kumar,&nbsp;Kanak Kanti Kar,&nbsp;Shivendra Srivastava,&nbsp;Sinan Rasiya Koya,&nbsp;Sudan Pokharel,&nbsp;Molly Likins,&nbsp;Tirthankar Roy","doi":"10.1016/j.jhydrol.2025.133938","DOIUrl":"10.1016/j.jhydrol.2025.133938","url":null,"abstract":"<div><div>Rain-on-Snow (ROS) events have been under increased scrutiny in recent years due to their devastating impacts. An ROS event is marked by rain falling on pre-existing snowpacks, which poses a considerable risk of flooding. In this study, we proposed a new approach to defining ROS events with potential flooding (ROS-PF) by establishing thresholds on rainfall, snow water equivalent, air temperature, and dew point temperature simultaneously, thereby overcoming the limitations of existing definitions. We also included a threshold at the 90th percentile over discharge to identify the ROS events that lead to actual floods (ROS-AF). Using this framework, we analyzed the frequency and trends of ROS-PF and ROS-AF events across thousands of basins in North America, Europe, Chile, Brazil, and Australia. Our findings indicate that the western US, central Chile, and central Europe are the most vulnerable regions with the highest frequency of ROS events, all of which showed a significant increasing trend. Additionally, we employed two causal discovery algorithms to uncover the causal structures leading to ROS flooding: Fast Causal Inference (FCI) and Fast Greedy Equivalence Search (FGES). Each algorithm offers a distinct path to infer causality from observational data. We combined the outputs of FCI and FGES to establish the final causal structure illustrating the causal mechanisms of ROS-based floods. This study also identified rainfall, soil moisture, snow water equivalent, maximum temperature, and DPT as critical drivers of ROS flooding, although the causal mechanisms resulting in ROS flooding differ across the four continents.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133938"},"PeriodicalIF":5.9,"publicationDate":"2025-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144669991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic development of global contiguous flash droughts: from an event-based spatiotemporal perspective","authors":"Dingkui Wang ,&nbsp;Xuezhi Tan ,&nbsp;Xinxin Wu ,&nbsp;Zeqin Huang ,&nbsp;Simin Deng ,&nbsp;Yaxin Liu ,&nbsp;Jianyu Fu ,&nbsp;Xuejin Tan ,&nbsp;Xitian Cai ,&nbsp;Bingjun Liu ,&nbsp;Haiyun Shi ,&nbsp;Long Yang ,&nbsp;Xiaohong Chen","doi":"10.1016/j.jhydrol.2025.133934","DOIUrl":"10.1016/j.jhydrol.2025.133934","url":null,"abstract":"<div><div>Flash droughts can induce serious adverse effects on local ecology due to their rapid intensification. However, individual flash drought events have not been thoroughly analyzed to demonstrate their dynamic evolution and changes. Here we use a 3-D connectivity algorithm to identify large contiguous flash drought events globally from an event-based perspective, which allows for effective tracking of their full spatiotemporal development. Results show that during 1980–2020, 2322 large contiguous flash drought events occurred and mainly distributed globally in nine hotspots, with a strong seasonal preference for warm seasons. Flash drought events of longer lifetime and travel distance are more likely to occur at the high-latitudes. The intensity, duration, and frequency of these events increase statistically significantly, while their affected area and translation speed decrease. Although regional variations in propagation patterns exist, flash drought events tend to propagate more toward the northeast. Across much of the globe, the preceding meteorological conditions in over 50% of flash droughts are marked by the concurrence of elevated regional temperatures and precipitation deficits. The dominant role of individual drivers exhibits notable spatial heterogeneity, largely influenced by the latitude and regional weather systems. Precipitation deficits tend to be the primary driver in monsoon-affected regions, while elevated temperatures predominantly govern flash drought onset in the high-latitudes of the Eurasian continent. Precipitation deficits primarily (38.9%) determine the intensity of flash droughts, while high temperatures play a dominant role (42.2%) in the duration of flash droughts. Our results provide a new perspective for future projection of drought events.</div></div>","PeriodicalId":362,"journal":{"name":"Journal of Hydrology","volume":"662 ","pages":"Article 133934"},"PeriodicalIF":5.9,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144669786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}