Study of NDVI, Land Surface Temperature using Landsat (TM) Data

STUDY OF NDVI, LAND SURFACE TEMPERATURE USING LANDSAT (TM) DATA

Course: Introduction to RS & DIP

Mirza Muhammad WaqarContact:

[email protected]+92-21-34650765-79 EXT:2257

RG610

Landsat TM(07-03-2010)

LMAX_BAND1 = 193.000LMIN_BAND1 = -1.520

LMAX_BAND2 = 365.000LMIN_BAND2 = -2.840

LMAX_BAND3 = 264.000LMIN_BAND3 = -1.170

LMAX_BAND4 = 221.000LMIN_BAND4 = -1.510

LMAX_BAND5 = 30.200LMIN_BAND5 = -0.370

LMAX_BAND6 = 15.303LMIN_BAND6 = 1.238

LMAX_BAND7 = 16.500LMIN_BAND7 = -0.150

Slope= (LMAX-LMIN)/(Max Gray)

Slope(B6)= (15.303-1.238)/(255)= 0.0551

Slope(B3)= (264+1.170)/(255)= 1.0398

Slope(B4)= (221+1.51)/(255)= 0.8725

Calculating Slope for Band= 3, 4 and 6

Radiance= Slope*DN + LMIN

LMAX_BAND1 = 193.000 LMIN_BAND1 = -1.520

LMAX_BAND2 = 365.000 LMIN_BAND2 = -2.840

LMAX_BAND3 = 264.000 LMIN_BAND3 = -1.170

LMAX_BAND4 = 221.000 LMIN_BAND4 = -1.510

LMAX_BAND5 = 30.200 LMIN_BAND5 = -0.370

LMAX_BAND6 = 15.303 LMIN_BAND6 = 1.238

LMAX_BAND7 = 16.500 LMIN_BAND7 = -0.150

R(3)= 1.0398 *B3-1.170

R(4)= 0.8725*B4-1.510

R(6)= 0.0551*B6-1.238

Calculating Radiance for Band= 3, 4 and 6

Radiance for Band 6

Calculating Radiance for Band= 3, 4 and 6

Calculating Brightness Temperature using Planck's Black Body Radiation Law

TB = K2/Log{(K1/R6)+1)}

Where:K1 = Calibration constant 1 (666.09 watt/m2 * ster * µm)K2 = Calibration constant 2 (1282.71 K)

Surface Temperature= TB /{1+( λ *BT/ρ*logε)}

TB= Brightness Temperature = λ Wavelength of emitted radiance (11.5 µm) = ρ h x c/ =1.438 σ x 10-2 mK ( =σ Boltzmann constant=1.38 x 10-23 J/K,

h=Planck’s constant=6.626 x 10-34 Js, c=velocity of light=2.998 x 108 m/s)

= ε Land surface emissivity

Calculating Surface Temperature

Calculating Land surface emissivity (LSE)- ε

LSE (ε) can be extracted by using NDVI considering three different cases Bare ground Fully vegetated and Mixture of bare soil and vegetation

For Band 6 of Landsat TM ε = 0.004*Pv + 0.986

Pv is the proportion of vegetation which is given by Pv = [(NDVI-NDVImin)/(NDVImax-NDVImin)]2

NDVI = [Ref(B4)-Ref (B3)}/{Ref (B4)+Ref(B3)}

Pv

Calculating Pv

Pv = [(NDVI-NDVImin)/(NDVImax-NDVImin)]2

LSE

ε = 0.004*Pv + 0.986

Calculating ε

Logε

Calculating ε

Surface Temperature= TB /{1+( λ *BT/ρ) *logε}

= λ Wavelength of emitted radiance (11.5 µm) = ρ h x c/ =1.438 σ x 10-2 mK ( =σ Boltzmann constant=1.38 x 10-23 J/K,

h=Planck’s constant=6.626 x 10-34 Js, c=velocity of light=2.998 x 108 m/s)

Calculating Surface Temperature

Land Surface Temperature (LST)