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Of particular current importance in the general problem of global climate change is the regional manifestation of this process. The focus of this paper is concentrated on the transitional natural zones: forest tundra (st. Salekhard), and forest-steppe (st. Omsk) of the West Siberian Plain. The study is based on data for ground air temperatures and precipitation at the mean-daily and mean annual level, covering the time interval from 1936 to 2012. The observations are grouped in three periods: from 1936 to 1970, from 1971 to 2006, and from 2001 to 2012 thus making it possible to identify trends in the behavior of mean annual indicators, examine the intra-annual and seasonal changes, and to carry out a typification according to thermal regime and humidification regime. Regional changes in mean annual air temperatures at st. Salekhard and st. Omsk are representative of the general features of temperature variation over the entire observing period. In the Subarctic, however, the warming period became more pronounced in 2001, whereas it started in the 1970s in the forest-steppe, which is borne out by an increase in the recurrence frequency of warm and normal (according to thermal regime) years during the aforementioned periods. The southern part of the West Siberian Plain has experienced a more intense warming than in the north. Analysis of the intra-annual behavior of mean daily temperatures at st. Omsk showed their steady increase during the time interval from 1971 to 2012; this is especially true in regard to a warm season. At st. Salekhard the dynamics of temperatures is more complicated in character. Observation showed comparable (in duration) time spans with alternating increases and decreases in air temperature. The annual precipitation amounts for the time intervals used in the comparison indicated that their mean long-term value in the zones under consideration has increased for the last 35 years by 26 mm at st. Salekhard, and by 15 mm at st. Omsk. Considerable changes of climate have been observed since the 1970s; in high and mid-latitudes, they differ greatly and have influence on phenological phenomena, the structure of seasonal rhythms, the conditions of functioning of landscapes, and on human economic activity. [ABSTRACT FROM AUTHOR]

The spatial distribution patterns of climatic changes in Yakutia are considered. For 26 meteorological stations of Yakutia we calculated the linear trend coefficients of climatic characteristics: air temperature (mean annual, January and July temperatures) and the mean annual amount of atmospheric precipitation from 1966 to 2016. Maps of climate change trends were compiled from linear trend coefficients. A spatial analysis of the zonal (regional) peculiarities of the climate of Yakutia has been carried out. An increase in air temperature was established for the 50-year period under consideration. It was found that the annual values of the air temperature trend are positive and, on average, a characteristic trend change interval is 0.3 to 0.6 °C/10 yr. Most of the meteorological stations recorded trends of air temperature with maximum values in winter and minimum values in summer. It was determined that the values of the trends in annual precipitation show different directions, and positive trends occur on more than 70% of the territory of Yakutia. Their maximum corresponds to the mountain-taiga regions of Southern Yakutia. Negative trends in precipitation with values of up to-15 mm/10 yr. are observed in tundra landscapes. The findings show that different regions of Yakutia respond differently to climate change. The trend of an increase in mean annual temperature is largely due to the rise in temperatures during the winter months. The rise in air temperature in Yakutia may be part of global warming. Over the last 50 years there has been an increase in the amount of precipitation in Yakutia as a whole. [ABSTRACT FROM AUTHOR]

A comparison is made of the calculated values of solar radiation incident on the upper atmospheric boundary with the measured values of surface temperature on the territory of the Crimean Peninsula. It is shown that the long-term temperature regime on the territory of the Crimean Peninsula is characterized by a stability. It is determined that the stability of the long-term regime of mean annual surface air temperatures is associated with the characteristics of the latitudinal distribution of solar radiation incident on the upper atmospheric boundary. The incident solar radiation increases in the regions of heat sources and decreases in the regions of heat sink. Stability of long-term mean annual values of surface air temperature is associated with the location of the Crimea on the boundary of the regions of heat sources and sinks. The study revealed the chronological structure of long-term changes in surface air temperature. The anomaly in the long-term surface air temperature variability is characterized by short-duration variations. An analysis is made of the chronological structure of interannual variability in surface air temperature on the territory of the peninsula. The dominant interannual and 2-3-year periodicities in the temperature regime variations are correlated with variations in incident solar radiation. In 62.7% of cases, the sign of interannual variability in surface air temperature corresponds to the sign of interannual variability in incident solar radiation. Thus it is shown that a small tendency in the long-term surface air temperature variability on the territory of the Crimean Peninsula, and the characteristics of its variations are determined largely by the specific character of the input and distribution of solar radiation incident on the upper atmospheric boundary. [ABSTRACT FROM AUTHOR]