Runoff of Russian Rivers under Current and Projected Climate Change: a Review 2. Climate Change Impact on the Water Regime of Russian Rivers in the XXI Century

Water Resources - The present overview is the second part of the article “Runoff of Russian Rivers Under Current and Projected Climate Change: A Review,” which focuses on modern...     

Variations of the Present-Day Annual and Seasonal Runoff in the Far East and Siberia with the Use of Regional Hydrological and Global Climate Models

A method of spatial calibration and verification of regional numerical physically based models of river runoff formation, incorporating runoff formation processes in the main river channel and its tributaries, was used to obtain a statistical estimate of the quality of river runoff calculation by conventional and alternative criteria focused on runoff reproduction in different phases of water regime and the characteristics of its variations. The analysis of the simulation quality of the annual and mean monthly river runoff (average runoff, standard deviation, and the coefficient of variation) at the near-mouth gages over the historical period with boundary conditions represented by data of global climate models showed the results to be satisfactory. This allows the proposed combination of climate and hydrological models to be used to study physically based regional variations of water regime under different physiographic and climatic conditions in the examined river basins with flood runoff regime (the Amur R.) and the predominant snowmelt runoff during spring flood (the Lena R.).     

Incorporating Natural Changes in Global Climate in Very-Long-Range Forecasting of River Runoff

A method is proposed for incorporating possible global changes in the state of the atmosphere, basing on K. Hasselmann’s theory of stochastic climate models, for assessing the significance of forecasts of variations of annual river runoff depth in the XXI century. The data used includes the results of river runoff simulation at warming, obtained using 21 IPCC climate models along with six IPCC scenarios of greenhouse gas emission, and MEI scenario. The significance index of forecasted runoff variations, i.e., the values of runoff depth increments divided by the standard error of forecasts was mapped. To demonstrate the role of the maps of significance index, which have been constructed taking into account forecast uncertainty because of the natural changes in global climate, those maps were compared with the maps of significance index calculated basing on other sources of errors. At large time scales, the uncertainty of runoff forecasts owing to natural changes in global climate plays the main role in assessing the reliability of forecasts in areas where greenhouse effect is strongest. Estimates of the significance index show that statistically significant changes in the annual runoff depth in the extreme northeast of Eurasia can be expected to occur not earlier than the late XXI century. In other RF regions, as well as in the majority of world areas, the forecasted changes in the annual runoff depth are comparable with the standard errors of the respective estimates or are less than they are.     

Present-Day Water Economy Balances of Major River Basins in the Russian Federation

Water economy balances of the major river basins in the Russian Federation for 1998–2002 are considered and their possible changes in the period up to 2010 are discussed. Consumptive water use and the feasibility of steady functioning of water users are assessed. River basins on the southern slope of the European Russia are examined in detail.     

Impact of Possible Climate Change on Extreme Annual Runoff from River Basins Located in Different Regions of the Globe

Water Resources - For 11 large river basins (the Rhine, Tagus, Ganges, Lena, Upper Yellow, Upper Yangtze, Niger, Mackenzie, Upper Mississippi, Upper Amazon and Darling) located on different...     

Impact Assessment of Climate Change and Human Activities on Runoff Variation in Coal Mining Watershed,NW China

Water Resources - The Kuye river watershed is a coal mining watershed in Northwest China. The study analyzed runoff change of year, high flow period and low flow period in the past 60 years based...     

Scenario Projections of Changes in Snow Water Equivalent Due to Possible Climate Changes in Different Regions of the Earth

Water Resources - The study was carried out under the international Earth System Model–Snow Model Intercomparison Project on ten experimental well-instrumented snow sites in different parts...     

Projecting Changes in Russian Northern River Runoff due to Possible Climate Change during the 21st Century: A Case Study of the Northern Dvina,Taz and Indigirka Rivers

Water Resources - Projected changes in river runoff due to possible climate change during the 21st century were simulated with making use of a physically-based land surface model SWAP and...     

On the Effect of Intermittent Nonstationarity of Long-Term Changes in the River Runoff

Water Resources - Based on the analysis of 162 longest (more than 100 years each) series of annual, maximal, and minimal runoff in rivers of different genetic types, the regularities of changes in...     

不同地区地震与太阳活动的统计关系研究

用时间序列分析和相关分析方法分别对华北北部地区1970～2006年和云南省及周边地区1965～2006年的地震活动与太阳黑子、耀斑活动的相关性进行了分析,得到的结论是,两处的地震活动与太阳活动均不相关.这与以往研究的结论不同,本文同时对产生不同结论的原因进行了初步分析.     

Assessing the Effect of Agricultural Production on the Organic and Biogenic Matter Runoff into the Psel River

Variations in the concentrations of dissolved organic and biogenic substances in waters of natural watercourses under the effect of natural and anthropogenic factors are considered. Seasonal and long-term dynamics of these concentrations in 1990–2001 are analyzed. The causes of an improvement in surface water quality are established, and the role of some changes in the agricultural production in the forest–steppe zone of the Central Black Earth Region of Russia is assessed.     

Streamflow of Russian Rivers under Current and Forecasted Climate Changes: A Review of Publications. 1. Assessment of Changes in the Water Regime of Russian Rivers by Observation Data

Water Resources - Publications on changes in river water regime in Russia under the conditions of current climate changes are reviewed. Most recent generalizations of such publications are...     

Mass,Volume and Velocity of the Antarctic Ice Sheet: Present-Day Changes and Error Effects

This study examines present-day changes of the Antarctic ice sheet (AIS) by means of different data sets. We make use of monthly gravity field solutions acquired by the Gravity Recovery and Climate Experiment (GRACE) to study mass changes of the AIS for a 10-year period. In addition to ‘standard’ solutions of release 05, solutions based on radial base functions were used. Both solutions reveal an increased mass loss in recent years. For a 6-year period surface-height changes were inferred from laser altimetry data provided by the Ice, Cloud, and land Elevation Satellite (ICESat). The basin-scale volume trends were converted into mass changes and were compared with the GRACE estimates for the same period. Focussing on the Thwaites Glacier, Landsat optical imagery was utilised to determine ice-flow velocities for a period of more than two decades. This data set was extended by means of high-resolution synthetic aperture radar (SAR) data from the TerraSAR-X mission, revealing an accelerated ice flow of all parts of the glacier. ICESat data over the Thwaites Glacier were complemented by digital elevation models inferred from TanDEM-X data. This extended data set exhibits an increased surface lowering in recent times. Passive microwave remote sensing data prove the long-term stability of the accumulation rates in a low accumulation zone in East Antarctica over several decades. Finally, we discuss the main error sources of present-day mass-balance estimates: the glacial isostatic adjustment effect for GRACE as well as the biases between laser operational periods and the volume–mass conversion for ICESat.     

Application of the Land Surface Model SWAP and Global Climate Model INMCM4.0 for Projecting Runoff of Northern Russian Rivers. 2. Projections and Their Uncertainties

Water Resources - The aim of this study was investigating the ability of the AOGCM INMCM4.0 and LSM SWAP to reproduce streamflow of nine northern Russian rivers located in the European Russia and...     

The Forms of Linear Structure of Overland Flow in Medium-Height Mountain Regions: Case Study of the Sikhote Alin

Water Resources - Large subsurface streams on steep slopes have stable positions with distinct catchment areas (drainage basins), linear shapes, and lengths of tens and hundreds meters. They form a...     

Climate and soil moisture environment during development of the fifth palaeosol in Guanzhong Plain

Based on weathering characteristics of the fifth palaeosol layer (S5) of four sections in Guanzhong Plain, the thickness of the weathered profile of the paleosol is determined to be greater than the ordi- nary soil, a weathered and leached loess layer thicker than 2 m. The distribution depth of the red argil- lans, the weathered and leached loess layer, Fe2O3, CaCO3 and Sr content under the S5 all indicate that the precipitation in Guanzhong Plain was over 900 mm at that time. The distribution depth of gravity water zone reached 4.2 m at least, and the soil moisture content was generally more than 20% within the range of 4.2 m. At that time there was sufficient soil moisture and no dried earth layer developed in Guanzhong Plain, suitable for the forest to develop. When this soil developed, the mean annual pre- cipitation was more than the annual soil moisture evaporation. The value of soil moisture balance was positive and the atmospheric precipitation could supply the underground water normally. Soil water was weak acidic in the middle and late stages when S5 developed in Guanzhong Plain. It was a kind of subtropical climate and even more humid and warmer than the northern edge of the subtropical climate zone in Guanzhong Plain when the S5 developed. At that time the subtropical climate was prevailing over the northern side and southern side of Qingling Mountains, showing the Mountains no longer to be the boundary between the subtropical zone and the temperate zone in China. The summer monsoon acted intensely and could go over Qingling Mountains frequently bring abundant precipitation.     

江西北部及邻区地震活动特征

利用不同时间尺度、不同震级下限的资料,分析了江西北部及邻区的地震活动时空分布特点。结果显示：本区地震活动成组现象明显．中强地震前中短期阶段的地震学异常特征主要表现为地震空区、地震条带或中等地震集中增强区。未来数年内本区还有可能发生中强地震,目前应当高度重视区域的震情发展趋势。     

Influence of agricultural development and climate changes on the drainage valley density of the southern half of the Russian Plain

The southern half of the Russian Plain is characterized by a relatively short history of intensively ploughed lands.The duration varies from approximately three centuries in the southern part of the forest zone to less than one century in some parts of the steppe zone.It was found that after cultivation,on more than 40％ of lands in river basins the drainage valley density (Ddv) decreased by 15-58％ in all landscape zones.In the first stage,the Ddv decrease was mostly associated with increasing surface runoff coefficient after cultivation of virgin lands with proportional decreases in groundwater runoff.In the second stage,usually after reaching areas of arable lands in river basins ＞ 60％,the volume of eroded sediments entering small fiver channels exceeded the transport capacities of the permanent water-courses.As a result,the river channels completely silted.In later stages,the sediment redistribution cascade within the small river basins of the Russian Plain stabilized because of the increasing proportion of sediment eroded from the basin areas and re-deposited before entering the river channels because of the increasing area of sediment sinks due to the increase in dry valley lengths and total areas.The morphological parameters of small valleys and groundwater discharges are the key parameters that affect the intensity of small river aggradation on the regional scale.     

Erratum to: Contemporary and Scenario Changes in River Runoff in the Don Basin

Water Resources - An Erratum to this paper has been published: https://doi.org/10.1134/S0097807821120010