Urban Heat Island in Moscow at different heights, depths and on the surface

Abstract

The urban heat island (UHI) in Moscow was for the first time studied not only at the ground air level, but also at different heights, depths and on the surface using stationary, radiosonde and satellite data. Long-term dynamics of the UHI intensity in the ground air layer has been estimated since the end of the 19th century both as traditional ‘maximal intensity’ (the difference between the city centre and rural zone), and as ‘average intensity’ (the difference between all urban and all rural stations). In recent years they have been 2.0 and 1.0 ºC, respectively. The quasi-stabilization of both parameters in the second half of the 20th century was probably the result of extensive city growth at that time; the new increase in the UHI intensity seems to be connected with the densification of urban development and heat sources in the last 20 years. The mean daily vertical extension of the UHI in the atmosphere is approximately 300 m. In the upper soil layer (up to 160 cm deep) the maximal UHI intensity was about 1.6-1.7 ºC half a century ago. The average UHI intensity at the field of the surface temperature in recent years is 2.7 ºC.