Thermal regime in the Rybinsk Reservoir under global warming

Presented are the results of studying the water temperature changes in the Rybinsk Reservoir during the ice-free period caused by the climate warming. Linear trends are revealed and estimated. The trend is observed for the period of 1976?C2008 towards the increase in the average water surface temperature during all months at the maximum rise rate of 0.89°C/10 years in July. It is demonstrated that the average water temperature in the reservoir in May?COctober has been above the norm since 1995.     

Problems of exploration level of hydrometeorological regime of the Northern Caucasus territory

The main problems of the study of the meteorological regime, climate, hydrology, snow avalanches, mudflows, and glaciers are considered. It is demonstrated that the level of their exploration on the plain territory is sufficient on the whole, however, the mountain territories are poorly studied. The opening of new stations including the automatic ones and the organization of snow-route observations are required. It is necessary to carry out the preparation and publishing of new handbooks on the climate and surface water resources and to create the catalogs of glaciers, snow avalanches, and mudflows on the basis of the modern topographic maps and satellite images.     

Long-term variations of wind regime in the free atmosphere over the European territory of Russia

The time series of seasonal average values and standard deviations of wind speed components at the isobaric surfaces of 850 and 200 hPa are analyzed on the basis of the data of upper-air observations carried out in 1961–2003 at 18 stations of the Russian Federation territory. The energy spectra of wind speed components in the first and in the second halves of the whole period under study are compared. On the whole, an increase in average values of U-component and decrease in average values of V-component took place both in upper and lower troposphere, and the largest variations occurred in winter season in the upper troposphere. Average coefficients of linear trends of average winter values for the whole region amount to 0.57 and ?0.62 m/s per 10 years for the wind components U and V at the isobaric surface of 200 hPa, respectively. The increase in the standard deviations of both components was registered in the upper troposphere in winter period almost on the whole territory. The average coefficients of linear trends of standard deviations at the isobaric surface of 200 hPa in winter for the whole region amount to 0.53 and 0.61 m/s per 10 years for U- and V-components, respectively. The intensity of the annual cycle and processes of intraseasonal scale both in the lower and upper troposphere increased in the second half of the whole interval under study.     

Synoptic variability of the thermodynamical state of Rybinsk Reservoir water masses

Presented is a brief characteristic of structurally new grid-box mathematical model for calculation of characteristics of hydrological regime of reservoirs of any size and residence time, morphological class and hydroeconomic purpose, with time resolution of 24 h and depth increment of 1 m. Presented are the results of its verification, as well as the fragments of results of diagnostic calculation of changes in vertical distribution of temperature, mineralization, and discharges of katabatic, density, wind drift and compensated flows in separate segments of four reaches of the Rybinsk Reservoir in case of weather changing for all seasons of two years with extreme flow.     

基于高空与地面观测的阿克苏河流域气候水文要素变化分析

本研究基于地面和高空资料,分析了阿克苏河流域1960—2015年的气候和水文变化特征,并探讨了高空气候变量在径流反演中的作用。结果表明,在全球变化背景下,阿克苏河流域地表温度呈显著升高趋势,线性倾向率为0.18℃/10a（-0.09~0.43℃/10a);流域降水总体呈增加趋势,增加速率为10.42 mm/10a（2.23~21.11 mm/10a)。阿拉木图、伊宁和库车3个高空探测站的0℃层高度总体呈上升趋势。相对于1960—1989年,1990—2015年3个站的0℃层高度分别增加了88.9 m、29.4 m和7.2 m。联合使用地面气温、降水和高空0°层高度资料,能显著提高阿克苏河流域夏季流量反演效果。     

Hydrological structure of the Sheksna River Deep of the Rybinsk Reservoir and water quality assessment by biological parameters

Peculiarities of formation and seasonal dynamics of hydrological structure of the Sheksna River Deep of the Rybinsk Reservoir are considered. The contribution of various genetic water types, including run-offs of the town of Cherepovets, to the formation of its water masses is established on the grounds of model calculations. It is shown, that the hydrological structure effects the distribution of hydrobionts in sewage disposal areas. The assessment of the contribution of Cherepovets run-offs to the change of total water salinity of the deep is given.     

Long-term summer temperature variations in the Pyrenees

Two hundred and sixty one newly measured tree-ring width and density series from living and dry-dead conifers from two timberline sites in the Spanish Pyrenees were compiled. Application of the regional curve standardization method for tree-ring detrending allowed the preservation of inter-annual to multi-centennial scale variability. The new density record correlates at 0.53 (0.68 in the higher frequency domain) with May–September maximum temperatures over the 1944–2005 period. Reconstructed warmth in the fourteenth to fifteenth and twentieth century is separated by a prolonged cooling from ∼1450 to 1850. Six of the ten warmest decades fall into the twentieth century, whereas the remaining four are reconstructed for the 1360–1440 interval. Comparison with novel density-based summer temperature reconstructions from the Swiss Alps and northern Sweden indicates decadal to longer-term similarity between the Pyrenees and Alps, but disagreement with northern Sweden. Spatial field correlations with instrumental data support the regional differentiation of the proxy records. While twentieth century warmth is evident in the Alps and Pyrenees, recent temperatures in Scandinavia are relatively cold in comparison to earlier warmth centered around medieval times, ∼1450, and the late eighteenth century. While coldest summers in the Alps and Pyrenees were in-phase with the Maunder and Dalton solar minima, lowest temperatures in Scandinavia occurred later at the onset of the twentieth century. However, fairly cold summers at the end of the fifteenth century, between ∼1600–1700, and ∼1820 were synchronized over Europe, and larger areas of the Northern Hemisphere.     

Long-term variations of solar radiation in Europe

Presented are the results of the analysis of the series of seasonal and annual means of short-wave solar radiation measured at 180 actinometric stations of Europe in 1964–2010. It is demonstrated that there are two strongly pronounced periods, namely, the decrease from the early 1960s to the late 1980s and the increase in the subsequent 20 years. Total solar radiation decreased by 1.8% per 10 years on average during the first period and increased by 2.9% per 10 years during the second period. The increase in solar radiation during the second period is observed at the majority of stations due to the increase in the direct solar radiation (by 8.3% per 10 years on average). The diffuse radiation decreased by 3.1% on average for that period. The highest values of the ratio of the diffuse radiation to the direct one were registered in the 1980s–early 1990s.     

Long-term variations of long-wave radiation in Moscow

Using the data of long-term (1958–2012) actinometric and meteorological observations of the Meteorological Observatory of Lomonosov Moscow State University, the observed and computed long-wave fluxes and the factors defining their variability are estimated. Obtained are the normals and determined are the limits of variability of effective radiation. Analyzed are the peculiarities of atmospheric back radiation. Demonstrated is the trend towards the decrease (in absolute value) in effective radiation caused by the increase in the atmospheric back radiation flux (E _a). The trend towards the increase in the atmospheric back radiation is determined by the increase in the values of meteorological parameters: cloudiness, atmospheric moisture content, and temperature. The content of aerosol and carbon dioxide does not affect the long-term variations of E _a registered in Moscow. Derived empirical formulae can be recommended for estimating the atmospheric back radiation and effective radiation of the Earth surface using meteorological observations.     

Long-term variations in thermal comfort in Vienna

Summary A human energy balance model is calculated using the homogeneous data set of Vienna, Austria (48°N and 16° E). Variations in the different stages of comfort since 1873 are discussed. The historical data are then used to generate scenarios of a changing climate and calculate the impact of these variations on thermal comfort.With 5 Figures     

Long-term variations of cyclone activities in East Asia

A statistical analysis is made of the temporal and spatial variability of cyclone activities in middle latitudes in East Asia for 52 years during the period from 1934 to 1985.Three principal tracks of cyclones are distinguished in East Asia almost all year around except for the disappearance of the south one in summer.A longer-term variation in frequency of cyclones passing over the Japanese Islands with a period of about 20 years is found, in addition to a shorter-term variation with a period of a few years. A significant decreasing trend in cyclone frequency is noted between the late 1960s to around 1980.     

Long-term changes of climate and hydrological regime in the Baltic region and their causes

A complex analysis is made of the variability of climatic, hydrological, and oceanological processes and environmental factors in the Baltic Sea region in the 20th century and at the beginning of the 21st century. The cause-and-effect relations between the climate dynamics over the North Atlantic and hydrometeorological conditions in the Baltic basin are established. Different variants of the North Atlantic Oscillation (NAO) indices were used as an atmospheric circulation intensity measure.     

Long-term variations of annual and growing season rainfalls in Nigeria

Summary Evidence for changes in the annual and growing season rainfall series for the period 1919 to 1985 in Nigeria are examined on a regional basis, using power-spectral and lowpass filter techniques, and the Mann-Kendall rank statistic. Four regions, the Coastal Zone, the Guinea-Savanna Zone, the Midland area and the Sahel, are used in the investigation of rainfall variation from south to north across the country.Quasi-periodic oscillations in the annual and growing season rainfall series are found to be concentrated in four spectral bands: 2.0–2.4, 2.7–2.9, 3.2–3.6 and 5.6–6.3 years. The spatial coherence of the fluctuations in annual and growing season rainfall is found to be limited to Nigeria south of 11 degrees north latitude. Evidence also emerges of a progressive decline in annual and growing season rainfall for northern Nigeria, north of nine degrees north latitude, for the period 1939–1985.With 5 Figures     

Long-term variability of ice formation dates on the rivers of the Votkinsk Reservoir catchment

Long-term variations of ice formation dates are studied using the long (more than 100 years) series of observations of ice regime on the rivers of the Votkinsk Reservoir catchment. Proposed is the methodological approach to assessing the long-term variability of these dates using both parametric and nonparametric statistical criteria.     

Long-term variations in the frequency of typhoons and their connection with various formation factors

Variations in the frequency of tropical cyclones in the Northwest Pacific in 1961-2015 and their connection with various factors are analyzed. The examined factors are the occurrence rates of the certain patterns of atmospheric circulation (according to the Vangengeim-Girs classification) in the Pacific-American sector, sea surface temperature in the North Pacific, and the position of the North Pacific High center. Steady relationships between these parameters are revealed.     

Long-term variations of surface air temperature at major industrial cities of India

Local temperature is one of the major climatic elements to record the changes in the atmospheric environment brought about by industrialization and urbanization. Long-term variations of seasonal and annual surface air temperature at six major industrial cities of India (Calcutta, Bombay, Madras, Bangalore, Pune and Delhi) have been studied, using data for the past 86 to 112 yr. Comparative analysis of the temperature data of six nonindustrial stations has also been done. The long-term change in the temperature has been evaluated by linear trend. Calcutta, Bombay and Bangalore have shown significant warning trend, while Delhi has shown a cooling trend. The trends at Madras and Pune are not significant. The nonindustrial stations did not show significant trends. In general, there was either a cooling tendency or cessation of warming, after the late 1950s at most of the industrial cities.