Remote sensing of land surface temperature

Lecture 8

Thermal infrared of EM spectrum

0.7 m

3.0 m

100 m

All objects have a temperature above absolute zero (0 K) emit EM energy (in 3.0-100 µm). Human being has normal

98.6 ºF (37 ºC) Our eyes are only sensitive to

visible energy (0.4-0.7 µm). Human sense thermal energy through touch. while detectors (sensors) are sensitive to all EM spectrum.

All objects (vegetation, soil, rock, water, concrete, etc) selectively absorb solar short-wavelength energy and radiate thermal infrared energy.

Details about thermal remote sensing refers to another lectureFor this lecture and lab, we focus on MODIS LST processing and application

Brightness temperature, and physical (surface) temperature

Through radiance recorded by a remote sensor, if we use the Planck equation, we can get a temperature, which we call brightness temperature Tb, which is less than the real physical (or surface) temperature T.

)1(2),(

)1(2),( )/5

2

)/5

2

kThckThcb e

hcTBe

hcTLb

)1ln( / bTkhcekhcT

h, Planck’s constant =6.626 x 10-34 Ws2

T, Kelvin (K)c, 3 x 108 m/sk, Boltzmann’s constant=1.38 x 10-23 Ws/K

L or B, radiance (Wm-2μm-1)c1=2πhc2=3.74 x 10-16 Wm2

c2=ch/k=0.0144 mK

MODIS land surface temperature and emissivity product led by Dr. Wan

http://www.icess.ucsb.edu/modis/modis-lst.html

Wan et al. 2002

The accuracy of temperature is better than 1 K, Wan (2008)

288289290291292293294295296297

0 20 40 60 80 100 120 140

Distance (pixel)

T (K

)

X Profile Y Profile NW-SE NE-SW

Xie and Ytuarte, 2005

Urban Heat Island of San Antonio downtown area detected by MODIS temperature product1:30 am, July 15, 2004

Dallas-Fort Worth Houston

El Paso/Juarez San Antonio

San Antonio Terra Day

285

290

295

300

305

310

315

320

B

and 1

B

and 8

Ban

d 17

Ban

d 23

Ban

d 29

Ban

d 43

Ban

d 49

Ban

d 56

Ban

d 64

Ban

d 74

Ban

d 80

Ban

d 86

Ban

d 93

Ban

d 102

Ban

d 108

Ban

d 114

Ban

d 121

Ban

d 129

Ban

d 135

Ban

d 141

Ban

d 150

Ban

d 158

Ban

d 166

Ban

d 182

Ban

d 188

Ban

d 194

Ban

d 201

Ban

d 210

Ban

d 216

Ban

d 222

Ban

d 228

Ban

d 234

Ban

d 242

Ban

d 249

Tem

pera

ture

DowntownInside 410Inside 1604Outside 1604

San Antonio Aqua Day

289

294

299

304

309

314

319

B

and 1

B

and 6

Ban

d 11

Ban

d 16

Ban

d 21

Ban

d 26

Ban

d 31

Ban

d 36

Ban

d 41

Ban

d 46

Ban

d 51

Ban

d 56

Ban

d 61

Ban

d 66

Ban

d 71

Ban

d 76

Ban

d 81

Ban

d 86

Ban

d 91

Ban

d 96

Ban

d 101

Ban

d 106

Ban

d 111

Ban

d 116

Ban

d 121

Ban

d 126

Ban

d 131

Ban

d 136

Ban

d 141

Ban

d 146

Ban

d 151

Ban

d 156

Ban

d 161

Ban

d 166

Tem

pera

ture

DowntownInside 410Inside 1604Oustide 1604

10:30 am

1:30 pm

San Antonio

2000-2008

2002-2008

San Antonio Terra Night

270

275

280

285

290

295

300

305

B

and 2

Ban

d 11

Ban

d 20

Ban

d 29

Ban

d 38

Ban

d 47

Ban

d 56

Ban

d 65

Ban

d 74

Ban

d 83

Ban

d 92

Ban

d 101

Ban

d 110

Ban

d 119

Ban

d 128

Ban

d 137

Ban

d 146

Ban

d 155

Ban

d 164

Ban

d 174

Ban

d 183

Ban

d 192

Ban

d 201

Ban

d 211

Ban

d 220

Ban

d 229

Ban

d 238

Ban

d 247

Ban

d 256

Ban

d 265

Ban

d 274

Ban

d 284

Ban

d 293

Ban

d 302

Ban

d 311

Ban

d 320

Tem

pera

ture

DowntownInside 410Inside 1604Outside 160410:30 pm

1:30 amSan Antonio Aqua Night

270

275

280

285

290

295

300

B

and 1

B

and 6

Ban

d 11

Ban

d 16

Ban

d 21

Ban

d 26

Ban

d 31

Ban

d 38

Ban

d 43

Ban

d 48

Ban

d 53

Ban

d 59

Ban

d 65

Ban

d 70

Ban

d 75

Ban

d 80

Ban

d 86

Ban

d 91

Ban

d 96

Ban

d 101

Ban

d 106

Ban

d 111

Ban

d 116

Ban

d 121

Ban

d 126

Ban

d 131

Ban

d 136

Ban

d 142

Ban

d 147

Ban

d 152

Ban

d 160

Ban

d 165

Ban

d 170

Ban

d 175

Ban

d 180

Ban

d 186

Ban

d 192

Tem

pera

ture

DowntownInside 410Inside 1604Outside 1604

San Antonio

2000-2008

2002-2008

Black areas are no date, due to cloud cover. So this image should not use

The Delaunay triangulation method is available under ENVI, at Topographic/Replace Bad Values

David Prado thesis, 2010

Source: Jeff Dozier

Active fire detection:MODIS fire and thermal anomalies products

Image caption: Fires in the Bahamas, Florida and Cuba (03 April 2004, 18:30 UTC) identified using MODIS Aqua and outlined in red on the MODIS 1km corrected reflectance product

http://modis-fire.gsfc.nasa.gov/index.asp