The work is devoted to assessment of solar energy resources for the territory of Moscow. The authors consider the various sources of input data on the incoming solar radiation - the long-term ground-based measurements and spe cialized data bases (NASA POWER). Verification of the NASA POWER data on the base of observations of weather stations in the Moscow region should justify its use under the calculation of resources and performance prediction of solar power plants. The work shows and discusses the results of calculations of solar energy potential on this territory.

Analyzed are the results of meteorological and environmental measurements performed over the 60-year period (1954–2013) at the Meteorological Observatory of Lomonosov Moscow State University. The significant positive temperature trend (0.04°C/year for 1954–2013) was obtained; it increased up to 0.07°C/year in 1976–2012. Considered are the features of seasonal variations of different atmospheric characteristics. Discussed are the type and causes of low-frequency changes in meteorological parameters, radiation balance components, radiation in different spectral ranges, and chemical composition of precipitation. Demonstrated are possible mechanisms of the more significant increase observed in air temperature in Moscow as compared with that in Central Federal District and their connection with the greenhouse effect in the urban atmosphere.

Considered are the conditions of the natural illuminance of Moscow during the period of smoke haze caused by forest and peat-bog fires in summer 1972,2002, and 2010. Assessed is the impact of such extreme conditions on total, scattered, and direct illuminance. The main attention is paid to the illuminance attenuation due to the smoke haze in the case of few-cloud weather. It is demonstrated that if smoke aerosol is present, direct illuminance decreases by 70% on average and total illuminance, by 30% as compared with similar conditions on the days with typical aerosol. Small increase in scattered illuminance is observed (by 45–90%). The analysis of illuminance in the cases of the haze of various intensity demonstrated that in the case of very intensive smoke screening, direct illuminance decreased to zero, total illuminance, by 70%, and increase in scattered illuminance slowed down. On such days horizontal visibility was equal to 100–200 m like under the conditions of thick fog.

Анализируются результаты измерений метеорологических и экологических величин за 60 лет (1954-2013 гг.), выполненных в Метеорологической обсерватории МГУ им. М. В. Ломоносова. Получен значимый положительный тренд температуры (0,04°С/год за период 1954-2013 гг.), который в 1976-2012 гг. увеличился до 0,07°С/год. Рассматриваются особенности сезонного хода разных характеристик атмосферы. Обсуждаются характер и причины низкочастотных колебаний метеорологических величин, составляющих радиационного баланса, радиации в разных спектральных диапазонах, а также химического состава атмосферных осадков. Показаны возможные механизмы наблюдаемого более значительного увеличения температуры воздуха в Москве по сравнению с Центральным федеральным округом и их связь с парниковым эффектом в городской атмосфере.

The results of long-term (1980-2011) photosynthetically active radiation (PAR) monitoring, which have been held at the Meteorological Observatory of Moscow State University (MSU MO) are presented. The PAR measurements are carried out within wavelength ranges 380-710 nm and 400-700 nm using modified thermoelectrically pyranometer (1980-2001) and LI-COR quantum sensor (from 1999 to the present) with the accuracy 7-10%. Main attention was paid to the variability of the magnitude of the relationship between the broadband total solar radiation (Q) and PAR (Q(PAR)). The dependence of this ratio (q(PAR=)Q(PAR)/Q) on various meteorological factors is investigated. The simple empirically derived model for PAR estimation is developed. Based on these methods the long-term variations of PAR during the XX Century in the Moscow region was obtained.

Estimates of some aerosol and radiation characteristics of the atmosphere in the summer of 2010 are obtained according to the results of the measurements made at the Meteorological Observatory (MO) at Moscow State University and are compared with the results of the measurements performed in 2002 and 1972 during the forest and peat fires. In contrast to 1972 and 2002, the period under study in 2010 is characterized by a greater frequency of the highest class of fire danger according to Nesterov, higher aerosol optical depths of the atmosphere up to 4.6, and a more significant weakening of solar radiation in different spectrum regions. In 2010 the smoke aerosol caused losses of the total shortwave radiation of 33%, visible radiation of 39%, ultraviolet radiation of 300–380 nm of 51%, and erythemal radiation of 63%. At the same time, an increase in the downward long-wave radiation to 40–50 W/m 2 under extreme aerosol optical depths is recorded.

The results of the study of the quantitative relationships between solar radiation (integral radiation and PAR), the content of nutrients, and the spring bloom parameters in the Ucha Reservoir are presented. Positive significant correlations between the date of peak bloom and the sum of light intensity over the period from the 35the to the 40th days (the upper reaches of the reservoir, station Pestovo) and the period from the 44th to the 49th days (the lower reaches of the reservoir, station Listvyanka) were determined on the basis of a retrospective analysis of the data from the period of 1993–2003. Regression equations were derived, which permit forecasting the start of phytoplankton growth in spring according to the results of solar radiation measurements. The sum of light intensity over the course of 50 calendar days in each years correlate positively with the phytoplankton abundance in spring (the highest daily number of algae and integral estimation of algae number in spring).