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The Yarlung Zangbo River (YZR) is the largest river system in the Tibetan Plateau, and its basin is one of the centers of human economic activity in Tibet. Large uncertainties exist in several previous climate change studies in this basin because of limited climate observations. In this paper, we used a meteorological drought index (Standardized Precipitation Evapotranspiration Index, SPEI) and a newly-released gridded climate forcing dataset based on high-quality climate station data to re-evaluate climate change in the YZR Basin during the period of 1961-2014. Results showed that precipitation experienced a statistically insignificant increasing trend at a rate of 6.32 mm/10 years, and its annual mean was 512.40 mm. The basin was sensitive to climate change in terms of the air temperature that significantly increased at the rate of 0.32 °C/10 years. This warming rate was obviously larger than that in many other regions. Analysis of SPEI showed that the basin had no obvious statistical trends in the number of dry/wet episodes, but the severity of dry episode aggravated in terms of duration and magnitude. This study provides a reliable analysis of climate change in the YZR Basin, and suggests this large Tibetan river basin is sensitive to climate change. [ABSTRACT FROM AUTHOR]

Watershed discharge (WD) in the alpine regions, such as the upper reach of Yarlung Zangbo River Basin (YZRB), China, could have changed severely in response to climate changes. Yet, how hydrometeorological variables varied at different time scales and how WD varied in response to hydrometeorological variables in the alpine regions remained questions to be answered. The ensemble empirical mode decomposition (EEMD) method was employed in this study to investigate the nonlinear climate change trends (averaged and extreme states) and the associated multiscale impacts on WD variations over the upper reach of the YZRB during 1961–2009. All investigated hydroclimatic variables, i.e., precipitation, temperature, and WD, were found to be varied nonlinearly with clear multiscale oscillations characterizing great differences in the oscillation periods, corresponding significance levels, and variance contribution rates, among which precipitation posed a weak impact on WD variations, while temperature played a significant role in WD fluctuations. Furthermore, among all temperature extremes, the dominant index affecting WD variations was TXm (annual mean of the daily maximum temperature) but not TXx (annual maximum of the daily maximum temperature) at both interannual and interdecadal scales, which might be caused by that TXx increased evapotranspiration and reduced WD. A significant correlation between temperature (both averaged and partial extreme states) and annual WD at both interannual and interdecadal scales indicated that a synchronous change existed between them. The present study provided first insight into how hydrometeorological variables varied at different time scales and how WD fluctuated in response to hydrometeorological variables over the upper reach of the YZRB, China. [ABSTRACT FROM AUTHOR]

Future hydrological extremes, such as floods and droughts, may pose serious threats for the livelihoods in the upstream domains of the Indus, Ganges, Brahmaputra. For this reason, the impacts of climate change on future hydrological extremes is investigated in these river basins. We use a fully-distributed cryospheric-hydrological model to simulate current and future hydrological fluxes and force the model with an ensemble of 8 downscaled General Circulation Models (GCMs) that are selected from the RCP4.5 and RCP8.5 scenarios. The model is calibrated on observed daily discharge and geodetic mass balances. The climate forcing and the outputs of the hydrological model are used to evaluate future changes in climatic extremes, and hydrological extremes by focusing on high and low flows. The outcomes show an increase in the magnitude of climatic means and extremes towards the end of the 21st century where climatic extremes tend to increase stronger than climatic means. Future mean discharge and high flow conditions will very likely increase. These increases might mainly be the result of increasing precipitation extremes. To some extent temperature extremes might also contribute to increasing discharge extremes, although this is highly dependent on magnitude of change in temperature extremes. Low flow conditions may occur less frequently, although the uncertainties in low flow projections can be high. The results of this study may contribute to improved understanding on the implications of climate change for the occurrence of future hydrological extremes in the Hindu Kush–Himalayan region. [ABSTRACT FROM AUTHOR]

The article presents a study that determines the findings of the participatory research process designed to identify responses for sustainable water management in a climate change in the upper Danube and Brahmaputra river basins. It describes the method used in the study in which socio-economic vulnerability was investigated and analyzed. The result of the study validates the motivations which triggered the design of the project, leading to the development of the twinning of the river basin.

The article presents a study that examines options to mitigate climate change impact for the adaptive integrated water resources management (IWRM) in the upper Danube and Brahmaputra river basins. It explores the method of the study that analyzes several options that can effective reduce climate change impact in the two river basins. The result of the study indicates that effectiveness of the twinning of the two river basins in reducing the effects of climate change.

The article presents a study that determines the vulnerability of the people to the climate change in upper Brahmaputra and Danube river basins. It cites the Human Dimension of the Twinning European and South Asian River Basins to Enhance Capacity and Implement Adaptive Management Approaches Project (EC-Project BRAHMATWINN) aimed at developing socio-economic tools for the effective inclusion of the assessment. The study uses stakeholder inputs to identify weightings of vulnerability domains.

The article presents a study that describes the development of a set of integrated indicators to support integrated water resources management (IWRM) and climate change in the upper Brahmaputra and Danube river basins. It explores the objective of the study, designed to provide stakeholders with update on the trends of the river basins and water resources and quantify the effects of climate change. The findings of the study indicate a strong link between the main issues that affect the basin.

The article presents a study that determines the effectiveness of integrated hydrological modeling in assessing the effect of climate change on the water balance via Danubia model. It explores the method of the study that employs the Danubia model to calculate the water balance components under different conditions in the large-scale mountain water sheds of the upper Danube and Brahmaputra. The findings of the study reveal the effectiveness of the model in assessing climate change effects.