Experimental research of Urban Heat Island effect for the Biggest Arctic Cities

As the urbanization continues worldwide more than half of the Earth’s population live in the cities (U.N., 2010), and in the Arctic region this rate is even much higher. Because of this the researches about urban climate is its impact on citizen’s life is actual and important part of modern climate science. Nowadays urban climate features are well studied for moderate and tropical zones (Oke, 1987), and the Urban Heat Island (UHI) effect is considered as most important among them.

In general, UHI makes a negative effect on people health (Buechley et. al., 1972) and energy consumption rates (Sailor, 2002). However, 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 cities in the Artic zone, which are located in Russia, remained undiscovered.

In this study, we consider the results of the experimental UHI research for four biggest cities, located to the north from the Arctic circle: Murmansk (approximately 303 000 inhabitants), Norilsk (180 000 inh.), Vorkuta (60 000 inh.) and Apatity (57 000 inh.). Source data for this reseach was obtained in several expeditions, supported by Russian Geographic Society, during the 2013-2014 and 2014-2015 winter seasons. 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.

Analysis of experimental data showed that Arctic cities, in spite of relatively small size, could have significant UHIs during the winter, with the difference between city center and surrounding landscape up to 10 ⁰C and its mean value about 1-2⁰C. Such results are especially interesting, because better accumulation of solar heating is considered as one of the most important reasons of the UHIs phenomenon existence, and in the Arctic winter solar heating is low or completely absent during the polar night. Therefore, we can suggest that strong UHIs, observed in the Arctic cities, are created mostly by release of the anthropogenicheat to the atmosphere.
significant UHI was observed in this city. However, the warmest place in Norilsk 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;