325
devices (Internet 1). The Brnik weather station is in a complete rural area and stands
on the SE edge of the Jože Pučnik Airport runway, over 100 m NW from it and more
than 1 km away from the nearest bigger building. First larger forest area is over the
airport’s runway more than 500 m away. The surrounding terrain is in general fl at,
open and grassy. Weather station is a climate one and the measurements are taken
automatically. The air distance between both weather stations is something more
than 17 km; the difference in altitude is 65 m (Fig. 12.2 ).
The UHI intensity-cycle was calculated for the period July 20. to July 26. 2011.
Its intensity was quite similar every day. The lowest intensity was present in the
morning of the second day, when the heating at the rural station has started earlier
than at the urban station and it was signifi cantly more rapid. Before a midday the
urban station became warmer, but in the evening rural station was cooling
signifi cantly faster. That caused that UHI intensity has reached the third highest
Fig. 12.2 Mean hourly air temperature and wind speed data in urban and rural station
12 Urban Heat Island in the Ljubljana City
devices (Internet 1). The Brnik weather station is in a complete rural area and stands
on the SE edge of the Jože Pučnik Airport runway, over 100 m NW from it and more
than 1 km away from the nearest bigger building. First larger forest area is over the
airport’s runway more than 500 m away. The surrounding terrain is in general fl at,
open and grassy. Weather station is a climate one and the measurements are taken
automatically. The air distance between both weather stations is something more
than 17 km; the difference in altitude is 65 m (Fig. 12.2 ).
The UHI intensity-cycle was calculated for the period July 20. to July 26. 2011.
Its intensity was quite similar every day. The lowest intensity was present in the
morning of the second day, when the heating at the rural station has started earlier
than at the urban station and it was signifi cantly more rapid. Before a midday the
urban station became warmer, but in the evening rural station was cooling
signifi cantly faster. That caused that UHI intensity has reached the third highest
Fig. 12.2 Mean hourly air temperature and wind speed data in urban and rural station
12 Urban Heat Island in the Ljubljana City