Validation of ASTER Surface Temperature Data with In Situ Measurements to Evaluate Heat Islands in Complex Urban Areas

Table 2

Surface temperature and emissivity of different surface fabrics measured onsite. Surface temperatures that were measured in shaded areas during the day were excluded.

Surface fabric	Emissivity	Surface temperature
		Daytime						Nighttime
		28 July 2012			23 September 2012			21 September 2012			28 September 2012
		No.	Mean (°C)	SD	No.	Mean (°C)	SD	No.	Mean (°C)	SD	No.	Mean (°C)	SD
Metal roof	0.99	1	44.5	—	1	36.8	—	1	19.1	—	1	17.0	—
Roof tile (brown)	0.98	12	55.9	5.2	7	47.7	4.0	12	15.6	0.6	12	13.6	1.7
Roof tile (black)	0.99	6	57.4	7.0	6	46.9	5.1	6	15.6	1.8	6	15.0	1.3
Roof tile (green)	0.99	1	51.7	—	1	41.5	—	1	17.9	—	1	16.9	—
Wooded board	0.95	4	69.0	0.6	6	52.2	1.9	9	12.1	3.3	7	12.2	0.6
Sand and bare	0.96	20	47.8	6.6	17	30.6	6.5	20	15.7	0.9	20	15.1	0.7
Sidewalk brick	0.96	40	50.1	3.9	40	39.3	5.0	47	17.8	2.1	46	17.9	1.2
Water	1.00	6	27.0	0.4	6	21.4	0.8	6	17.3	1.2	6	19.9	0.4
Tree and lawn	0.97	67	37.7	3.3	88	28.4	4.1	92	14.2	2.1	91	15.3	1.2
Asphalt	0.96	75	58.5	4.2	53	45.5	3.7	76	19.6	1.3	75	18.7	1.2
Green roof	0.93	7	40.0	3.9	5	26.2	3.0	7	15.9	1.0	4	16.7	1.0
Urethane	0.96	2	66.2	1.1	2	49.3	0.2	2	15.3	0.1	2	14.4	0.5
Artificial turf	0.96	6	56.1	3.2	6	39.9	1.2	6	17.0	0.9	6	16.8	0.7
Gravel	0.98	14	52.3	3.6	14	37.5	2.4	15	13.9	1.1	15	15.0	1.1
Concrete	0.97	8	54.2	2.6	8	40.5	2.6	9	19.7	0.8	9	18.8	0.7
Concrete roof (green)	0.98	7	57.4	2.4	4	43.0	3.5	5	18.1	1.2	5	18.0	0.6
Concrete roof (gray)	0.98	16	58.7	2.7	13	43.7	4.1	15	19.9	2.2	15	18.4	1.8
Tile	1.00	5	48.7	7.0	6	30.5	4.1	6	19.6	1.0	6	17.7	0.4
Flagstone	0.96	5	57.2	1.6	6	42.1	2.3	6	15.7	1.8	6	17.7	0.5
Granite	0.98	1	48.0	—	1	41.3	—	1	21.4	—	1	19.3	—
Homogeneous lawn	—	6	43.5	6.9	6	33.0	1.8	6	12.8	0.8	6	12.3	0.5
Homogeneous sidewalk brick	—	6	62.0	1.1	6	46.2	0.8	6	15.3	0.5	6	19.3	0.8