ИСТИНА

Modern prospects of intensification of socioeconomic activity and building new settlements in Arctic zone requires better understanding of the urban-caused microclimatic features and their behavior in the conditions of arctic and sub-arctic climate. While in moderate and tropical climate zones urban heat island (UHI) seems to have negative effect on people health (Buechley et. al., 1972) and energy consumption rates (Sailor, 2002), for arctic cities positive effect could be expected during long winter, when UHI could mitigate severe climatic conditions within urban areas and provide the economy of fuel for house heating. However, until nowadays knowledge about UHI of polar cities was very poor, the only existing researches considered small towns in Alaska (Magee et. al., 1999), while UHI of the biggest arctic cities, which are located in Russia, remained undiscovered. In this study, we consider the results of research of the UHI of Norilsk (second biggest city over the Polar Circle with aprox. 180 000 inh.) and Apatity (fifth biggest polar city with aprox. 60 000 inh.), which were obtained during the expedition of Russian Geographic Society during the 2013-2014 winter season. Expedition to Norilsk took place at December, in the middle of polar night, and expedition to Apatity was organizes in the end of January. Field measurements in these cities included installation of several automatic weather stations (AWS) and the net of small temperature sensors (iButton) in the city and surrounding landscape and car-based temperature sounding of the city with AWS. Additional information, such as measurements of MTP-5 temperature profiler and surface temperature data, provided by MODIS remote sensing system, were used for verification and confirmation of the results, obtained by experimental measurements. Analysis of experimental data and additional information showed existence of significant UHI with the difference between city center and surrounding landscape up to 6-7 ⁰C with mean value about 2⁰C. Such values are rather high as for Apatity, which is, actually, relatively small town, as for Norilsk, where measurements were made in the middle of polar night, when anthropogenic heat flux is the only factor forming the UHI. Measurements in Norilsk shown interesting spatial feature of temperature distribution: the warmest place was discovered not in the center of the city, but at the edge of the city near unfreezing lake, which is used for cooling industrial plants and releases anthropogenic heat to atmosphere. Economic effect of the UHI, connected with economy of fuel for house heating, was roughly estimated by hundreds of thousands - first millions EUR per year, for this assessment a simple statistical model of centralized urban heating system was used. References: 1. Magee N., Curtis J., Wendler G., The Urban Heat Island Effect at Fairbanks, Alaska// Theor. Appl. Climatol. 1999. V. 64, pp 39-47; 2. Buechley RW, Van Bruggen J and Truppi LE Heat island equals death island?// Environmental Resourses. 1972. V. 5. PP. 85-92. 3. Sailor, D. J. Urban Heat Islands, Opportunities and Challenges for Mitigation and Adap-tation (2002). Sample Electric Load Data for New Orleans, LA (NOPSI, 1995)// North American Urban Heat Island Summit. Toronto, Canada. 1-4 May 2002. Data courtesy Entergy Corporation;