H. Saaroni et al., Spatial distribution and microscale characteristics of the urban heat island in Tel-Aviv, Israel, LANDSC URB, 48(1-2), 2000, pp. 1-18
Citations number
39
Categorie Soggetti
Environment/Ecology,"EnvirnmentalStudies Geografy & Development
A significant urban heat island (UHI) was identified in Tel-Aviv on a stabl
e winter day. The UHI detection was performed using air temperatures at bot
h the roof and the street levels (using fixed-station and car-traverse meas
urements) and at the surface level (using an airborne thermal video radiome
ter [TVR]). Whereas the complex microscale characteristics of the UHI studi
ed by the TVR at the surface level showed variations of up to 10 degrees C,
at the street level, air temperature variations of 3-5 degrees C were iden
tified between the city center and the surrounding areas. It was found that
during the nighttime, the warm Mediterranean Sea has a moderating effect o
n the roof-level temperatures, whereas, at the street level, the urban heat
island is more pronounced. The combined method of monitoring the UHI from
different levels and on different scales for the first time enabled a spati
al assessment of the city's UHI and its diverse thermal coverage characteri
stics. The thermal differences of neighborhoods, urban activity and urban c
omponents were compared. It was demonstrated that the city cover plays an i
mportant role in the thermal activity of Tel-Aviv. A similar UHI spatial pa
ttern was obtained using isotherm maps, generated from the air temperatures
at street level, and thermal images, generated by the TVR at the surface l
evel. It war concluded that there are differences in the magnitude of the U
HI at different levels of the canopy layer and at different times, but the
UHI pattern has similar trends. (C) 2000 Elsevier Science B.V. All rights r
eserved.