A comprehensive analysis of air temperature (Ta) dynamics in "local climate zones" (LCZs) of Novi Sad (Serbia) was based on measurements from 17 stations during 3 years. Hourly changes of Ta, cooling rates (CR), heating rates (HR), and urban heat island (UHI) intensity were assessed on seasonal and annual level and during heat wave (HW) and cold wave (CW) periods. Substantial differences are observed for minimum (Tmin) and mean temperatures (Tmean) between LCZs. Two-phase nocturnal cooling was recognized with the first cooling phase characterized by intensive LCZ dependent cooling starting at 1-3 h before sunset and lasting until 3-4 h after sunset. The second cooling phase lasts until sunrise and is characterized by less intensive and LCZ nondependent cooling. The most intensive cooling (CRpeak) was observed in first cooling phase of HW and ranged from - 1.6 °C h-1 in street canyon (LCZ 2) to - 3.9 °C h-1 in forest (LCZ A). Furthermore, a new cooling indicator (CRtotal) was introduced. Due to cooling differences, the most intensive UHI of 5.5 °C was noticed between LCZs 2 and A at sunset + 1 h during HW. Two-phase diurnal heating was also recognized in LCZs with the first heating phase characterized by intensive LCZ dependent heating starting at sunrise and lasting until 4-7 h afterwards. The most intensive heating (HRpeak) ranged from 2.0 °C h-1 in street canyon to 3.0 °C h-1 in industrial area (LCZ 8) during HW. The second heating phase lasts until sunset and is characterized by less intensive heating and smaller HR differences between LCZs.
Keywords: Cooling rate; Heating rate; Local climate zone; Mid-sized city; Urban heat island; Urban meteorological network.