The object of the study is the maximum daily air temperature during the months of the year over 1991-2016 by the data of 186 meteorological stations of Ukraine. Extreme values of the maximum daily temperature equal to or exceeded their 95th (Tmax95p and above, ºС) percentile were taken as extreme. The article sets the dates (137 cases) of extreme values of maximum air temperature on more than 60 % of the territory. For these dates, 13 meteorological parameters were selected: average, minimum, and maximum air temperatures; average, minimum and maximum relative humidity; station and sea-level pressure; average, maximum (from 8 synoptic hours) wind speed; rainfall; height of snow cover. The purpose of this work is to determine the correlation coefficient (K), in particular, statistically significant (K≤-0.6, K≥0.6), on these dates between selected meteorological parameters at 186 meteorological stations of Ukraine for 1991-2013. The density of the cases of statistically significant dependence between the meteorological parameters in extremely warm days in separate seasons is determined. In extremely warm days, meteorological parameters and areas with statistically significant correlations at K≤-0.6 were detected: T and F (focally in southern and some western regions with significant density) − in winter; T and F (with the highest density ubiquitous or almost ubiquitous), P and V (in a large number of regions, usually west or right-bank, but with less frequency) − in the transition seasons, and in the autumn between − T and F (in the south with smaller density) and P and F (in some areas of the north, northwest, west, lower east). In all seasons, such a correlation between other meteorological parameters had a focal distribution, usually with a smaller density. In these days, a focal distribution with a small frequency of dependencies at K≥0.6 was found between the meteorological parameters detected (F and V in transition seasons, T and F in winter), except for similar ones. However, such dependence is observed between T and V in some regions in winter and autumn and in some areas of south, southeast, east with a smaller density. The study of the maximum daily temperature is relevant, because from the level of natural hydrometeorological phenomena it is accompanied by dangerous phenomena, negatively affecting the weather dependent industries.

Based on the data of maximum daily near-surface air temperature (MSAT) taken from 186 meteorological stations of Ukraine the parameters of extremality with relation to maximum air temperature for different time periods as well as deviations between them during cold and warm periods of the year were calculated. Regionalization of Ukraine was carried out in order to identify climate-vulnerable regions by means of comparison, overlapping and match of the areas with the highest values towards selected extremality thresholds. The conclusion about general increase in extremality over the last decade with relation to a climatic standard is made, the areas with the greatest vulnerability are outlined, and the areas with increase in extremality degree are identified. During both periods of the year certain areas in the southern, central and eastern parts of Ukraine are considered, based on maximum air temperature data, as the most vulnerable ones. During both periods of the year over 2001-2010, as compared to 1991-2000, increase of recurrence of extreme values of average maximum of air temperature was observed: in March and December during the cold period and also from May to July, and in case of EHMP event – in August. Distribution of maximum air temperature of the EHMP category, in comparison to the category of extreme values, specifies and localizes the regions with the greatest vulnerability. The areas of the highest vulnerability during the cool period comprise the extreme west, south-western and southern regions and during the warm period – southern, south-eastern regions and the extreme east of Ukraine. The spatial distribution of the extreme values of the MSAT for the warm period has a predominantly meridional orientation. During both periods of the year regions in the south (areas of Black Sea region, Crimea, boundary subregions in the south) areas in the east and center of Ukraine affected by extreme MSAT values are the most vulnerable; in 2010-2014 this influence intensified. Increase in the vulnerability based on the maximum air temperature occurs on the background of certain changes in the atmospheric circulation, under conditions of anticyclonic fields prevalence throughout the year along with increase of the temporal exposure to the elementary synoptic process. On the other hand, the aforementioned increase of recurrence of extreme hydrometeorological phenomena is a consequence of sharp changes of synoptic situation, which is especially the case after a period of settled weather. The conclusion that atmospheric circulation is a main agent responsible for extreme weather and that it is not studied completely so far was made.

Amid political and, consequently, economic and environmental problems engulfing Ukraine one of the today's challenges consists in studying the possibility of use of natural potential of renewable energy sources. Resources of solar radiation have no negative impact on the natural environment and human activity. Therefore development of helioenergetics and at the same time climatic substantiation of solar power plants use research become more and more important. The purpose of this article is to evaluate of the solar radiation potential opportunities for implementation of technical innovations within the territory of Ukraine and to identify prospects of helioenergetics development. Special indicators of solar radiation components for 1961-1990 s are showed. Using the method of mathematical statistics we defined a value of direct solar radiation contribution forming a part of the total radiation for the warm season (April-September). During the period of 1991-2015 an increase of solar radiation climatic resources relative to climatological standard norm of 1961-1990 was revealed. Over 2001-2015 annual direct and total solar radiation values increased even more in comparison to 1991-2000. Increase of duration of sunshine was also observed. Due to changes of radiation characteristics special indicators of solar for 1991-2015 were specified. The prospects of solar radiation use in helioenergetics proved their feasibility in Crimea, steppe zone, eastern part of forest-steppe zone and even in some parts of Polissya. Comparing to previous years, in terms of sunshine duration over 2000 hours per annum the territory expanded northward. Restrictions on innovations implementation apply to western forest-steppe zone and mountainous areas of Ukrainian Carpathians. Increase of solar radiation regime components determining the feasibility of solar power energy resources form the basis for their countrywide use.

The article presents the results of the study of the determination of the correlation connection between a number of meteorological values at the beginning of the deposition of ice on the wires of a standard ice-cream machine in certain months of the cold period of the year on the territory of Ukraine during 2001-2013. The research was conducted for 3 winter months, as well as for March and November. The pair of meteorological parameters have been determined at the beginning of the deposition of ice that have a statistically significant correlation coefficient and a spatial-temporal distribution of the distribution in certain months across the territory of Ukraine has been obtained. The most common variant of the statistically significant connection between individual meteorological parameters was the connection between the temperature of the water column (average, maximum, minimum) and relative humidity of air (average, maximum). Thus, for almost all months studied, a statistically significant correlation between the temperature of the vapor (average, maximum, minimum) and relative humidity of air (average, maximum) was established. For the winter months, the correlation coefficient of this connection was positive, and for March and November, it was negative. A widespread version of a statistically significant connection was the relationship between the air temperature (average, maximum, minimum) and the height of the snow cover. This connection for the months studied turned out to be negative. The variants of negative statistically significant connection between average wind speed and average relative humidity of air (January-February, December), average and maximum wind speed and sea-level pressure (November), and also between daily amount precipitation and snow (March), daily rainfall and wind speed (average, maximum), and pressure at sea level (November). During the months of the cold period of the year, statistically significant connections between the air temperature (average, maximum) and pressure at sea level (November), wind speed (average, maximum) and average humidity (January, December), pressure on sea levels and average relative humidity (March). Also, there were isolated cases of statistically significant correlation between snow and sea level pressure (December). The most frequently statistically significant connections between meteorological values at the dates of deposition of ice on the wires of a standard icing machine were observed at stations in the central, northeastern, eastern and separate southern regions.

o predict the possibility of ice deposits on the territory of Ukraine in the winter season, an analogous approach is proposed using the construction of the equations of the linear discriminant function. For this, the correlation coefficients between 13 meteorological values (per day) at the start dates of ice deposits at all stations of Ukraine were calculated. Significant correlation coefficients were determined between individual meteorological variables, such as average air temperature, maximum, minimum average air humidity, average wind speed, and atmospheric pressure at sea level. It is these quantities that were used to construct the equations of the linear discriminant function and for the dates of the actual formation of ice deposits and the further forecast of its formation from a three-day lead time. As a result of the calculations for the winter season of 2001-2013 an equation of the linear discriminant function was obtained for the dates of the actual formation of ice deposits and a sufficiently high justification was obtained. Also, to predict the possible formation of ice deposits with a three-day lead time, a prognostic function of linear discriminant analysis was obtained to determine possible such deposits for the winter season of 2001-2010. On the example of the regional centers, a satisfactory assessment of the justification on an independent material for the winter season of 2011-2016 was obtained. Thus, in constructing linear discriminant functions to determine the possibility of such an adverse event as ice deposition, a number of conclusions were obtained: – The sufficiently high validity of the discriminant functions of extreme meteorological phenomena (ice deposits) for the winter season 2001-2013 was obtained. It ranges from 91 % (for the data set at selected dates with ice deposits) up to 90% (for an array of data at the date of extreme cold ). – A sufficiently high estimate of the validity of the independent material for the winter season 2014-2016 was obtained. It is up to 78 % (for an array of data on extreme cold dates and from 90 % ( for an array of data on selected dates with ice deposits) . – The prognostic function of linear discriminant analysis was obtained to determine possible (with 3-day timeliness) extreme meteorological phenomena (ice) during the winter season 2001-2010, using only meteorological values with statistically significant correlation, namely, the maximum air temperature; average humidity; and average wind speed. – Sufficiently significant and satisfactory validity of the prognostic functions of possible (with 3-day timeliness) extreme meteorological phenomena (ice deposits) for the winter season 2001-2010 was obtained.