**2.2.1 Loose, earthen materials**

Surfaces of loose materials, such as soil, sand and gravel, are seldom found in the urban open spaces of Athens. The few surfaces that were noted and whose temperatures were measured in this study were completely dry. Until solar noon (around 13:30 local time for Athens, Greece near the summer solstice), the measured surface temperatures were very high (Table 1). After this time, most loose materials surfaces cooled down by 2 to 3 oC every half hour, reaching the air temperature by sunset (19:30 to 20:00).
