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Copyright of Advances in Water Science / Shuikexue Jinzhan is the property of Editorial Board of Advances in Water Science 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 Advances in Water Science / Shuikexue Jinzhan is the property of Editorial Board of Advances in Water Science 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.)

Because of global climate change and human activities, the occurrence frequency of extreme precipitation events is increasing steadily, which causes devastating flood disasters. The stability of a human body can be compromised when exposed to floodwaters, which definitely threatens the life of a human being. Therefore, the investigation into mechanisms and criteria of human instability in floodwaters can provide scientific bases for urban flood risk assessments and hazard reduction measures, and can also benefit the ability of emergency response. This paper summarizes existing studies on instability mechanisms and criteria for people in floodwaters. Based on the summarization, the application scope, advantages and disadvantages of these existing criteria for human instability are evaluated in detail. Even though the calibrated formulas based on mechanical analysis and measured data involve some simplifications, they can reflect the critical mechanical condition of human instability in floodwaters, and therefore show better universality in practice. Given the limitations and shortcomings of the existing studies as well as major threats in current urban flood disasters, this study also presents key future research directions, including the instability mechanisms and criteria of pedestrian evacuation in actual flood conditions and from flooded stairs; using big data technologies to obtain and analyze online resources of flood instability videos and images, and reasonably estimate the critical instability state to construct a dataset of body instability in floodwaters; conduct in-depth studies on the influence of body posture adjustment on flood hazard degree. Besides, it is necessary to promote the application of human instability criteria in the field of urban flooding disaster prevention and reduction, in order to minimize the disadvantageous impacts of urban flood disasters. [ABSTRACT FROM AUTHOR]

The significant changes in the cryosphere have produced a series of effects on the cryospheric hydrological processes. This paper comprehensively reviews the recent 20 years, especially the new progress in the research on the changes in cryospheric hydrological processes in China, which mainly include glacial meltwater, snow melt runoff, and frozen ground hydrology. The main progresses in the study on changes in glacial melt water manifest as: a comprehensive study on glacial meltwater at different scales was carried out, it was found that the glacial meltwater showed continuously increase, and whether the "peak point" of the glacial meltwater have appeared has scientifically identified and some basic understandings has obtained, and the modelling on glacial melt water process had made significant progress. In the study on snowmelt runoff changes, the snowmelt runoff contribution rate to river runoff in various basins were basically grasped by estimating the snowmelt runoff and found that the snowmelt runoff changes in China vary greatly, and it increased in some basins while decreased in some basins. The changes in the start melting period in China are universal with other basins in the world, and the prominent feature is the advance of the peak value. In the study of frozen ground hydrology, the studies on the relationship between surface water, interflow in active layer soil, supra- permafrost water revealed the coupling mechanism of gravity and thermodynamics in the formation of runoff in permafrost regions. The impacts of permafrost change on surface runoff has already appeared, which mainly appears as increase in the winter ( dry season) runoff. It also found that the permafrost degradation has a direct replenishment effect on river runoff, and the amount of recharge may have reached a certain level in some basins. [ABSTRACT FROM AUTHOR]

The East Asian summer monsoon brings a large amount of precipitation in East China every year, which is the main source of water resources for China. At the same time, it often causes the severe flooding disasters. The Chinese meteorologists and hydrologists have realized that the moisture transport intensity, the extent and persistence of summer monsoon may play a crucial role in extreme rainstorm processes. This branch of moisture transport belt may be termed as the East Asian summer monsoon moisture transport belt. It can be categorized in the atmospheric river (AR) coined internationally, but it is not a fully same conception, due to its unique regional feature of the East Asian summer monsoon. The monsoon moisture transport belt is a main producer of excessively heavy rainfalls and disastrous floods in this region. Based on the data of the past hundred years, this paper made an update re view of the characteristics and formation reasons of the East Asian summer monsoon moisture transport belt. Taking the five strongest continuous heavy rain processes in the Haihe River, Yellow River, Huaihe River and Yangtze River in the past hundred years as examples, the important role of the monsoonal moisture transport belt is analyzed. Finally, it is proposed that climate warming can affect the global water cycle through four aspects, including holding more water vapor in the atmosphere, changes of the atmospheric circulations and radiation forcing with climate warming as well as the regional impact of aerosols. [ABSTRACT FROM AUTHOR]

Tropical cyclone(TC) is the most harmful weather system in China,so analyzing and understanding the new characteristics of Chinese coastal landfall TCs is of great significance for disaster prevention and mitigation. In accordance with the meteorological data of the past 70 years,the characteristics of Chinese coastal landfall TCs are studied by utilizing statistical methods. The results illustrate that there is obviously varying in characteristics of Chinese coastal landfall TCs under the circumstances of climate change. The frequency of landfall typhoon is higher than that of previous years,the intensity and maximum value are increasing and the instability of annual mean intensity is growing in recent years. It is also found that the higher the intensity of TC is,the narrower the latitudinal zone of TC generation is,and the closer it is to the equator. The relationship named"φ—m"is established between the time and latitude of high intensity TCs(STY & SUPER TY),and it is verified that the length of typhoon season is negatively correlated with the first cyclone day and is not affected by El Ni1 o phenomenon. The length of typhoon season is conformed to normal distribution and its probability density formula is given in this paper. [ABSTRACT FROM AUTHOR]

Since there is no consensus about how to assign weights in Global Circulation Model(GCM) ensemble,this paper uses the Dempster-Shafer(DS) evidence theory to synthesize the following three the basic probability assignment(BPA) methods:the equal probability,the probability for statistic characteristics of the mean annual inflow,and the probability based on the relative monthly inflow variation.Then,DS evidence theory-based Adaptive Operating Rules(DS-AOR) are derived,in order to mitigate the adverse effect of climate change.The objective is to maximize the weighted average annual hydropower generation for all future scenario,and then the Simulation-Based Optimization(SBO) method is implemented to optimize the parameters of DS-AOR.The case study of the Jinxi Reservoir shows that:under uncertain future climate change,DS-AOR is an effective and robust strategy.Compared with Historical Operating Rules(HOR) and adaptive operating rules based on Equal Weights(EW-AOR),DS-AOR results in an increase in hydropower benefits by 0.76×108 kWh and 0.61×108 kWh,and an increase in hydropower reliability by 0.5%-11.17% and 3.50%-9.34%,respectively,and it performs more robustly.It is concluded that DS-AOR facilitates adaptive reservoir management under climate change. [ABSTRACT FROM AUTHOR]

Ecohydrology provides a framework to assess pressing environmental issues related to water and ecological degradation of wetland ecosystem.The ensuing discipline,wetland ecohydrology,can thus be used to promote conservation and rehabilitation programs,integrated water resources management as well as watershed-scale climate change mitigation measures.In this paper,we summarize the historical development of wetland ecohydrology using literature bibliometric analysis.We present a comprehensive survey of major research programs and key academic conferences on wetland hydrology,ecohydrology and water resources.Three developmental eras of wetland ecohydrology are broadly proposed:(1) the embryonic era(the 50-80th of the 20th century),(2) the developement era(the 90th of the 20th century) and (3) the flourishing era(from 2000 up till now).Each area is characterized by representative research achievements;illustrating the progress of wetland ecohydrology.We conclude that future research on wetland ecohydrology will primarily focus on the study of:(1) multi-factors,multi-processes and multi-scale interactive mechanisms between ecology and hydrology of wetlands;(2) response mechanisms of wetland ecohydrology to climate change and potential adaptive regulations;(3) coupled hydrological-ecological-social interactions and mutual feedback mechanisms of wetland systems;(4) integrated water resources management for efficient allocation of water to wetlands.Finally,given the current situation,we present preferential research areas and suggestions for future development of wetland ecohydrology in China. [ABSTRACT FROM AUTHOR]

Copyright of Advances in Water Science / Shuikexue Jinzhan is the property of Editorial Board of Advances in Water Science 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.)