MODIS VegetationIndices

Alfredo Huete

Kamel Didan

Tomoaki Miura

Wim van Leeuwen

Terrestrial Biophysics and Remote Sensing lab

University of Arizona

MODIS Standard VI ProductsMOD 13A2

1 km and 16-day

✷ Normalized Difference Vegetation Index(NDVI)

✷ Enhanced Vegetation Index (EVI)

✷ Quality Analysis (QA) Image

1 kmNDVI

1 kmEVI

NDVI QA

Miura T., et al./TBRS

EVI,1km

NDVI

EVI

MOD13A2: Scan Noise

Description: The striping observed in L1Bpropagates into NDVI and EVI. The effects of thestriping on the compositing algorithm can also beseen in the average view zenith angle SDS.

NDVI, EVI, and View Zenith AngleSDS

MOD13A2.A2000065.h08v05.hdfTile ID

SD_MOD13_00131bCase No.

EVI

View ZenithAngle

EVI

BlueReflectance

MOD13A2: Blue Reflectance and EVI

Description: Composite Blue reflectance havemany missing data, which propagate to EVI. Themissing blue reflectance was caused by both theblue band quality and the compositing algorithm.The compositing algorithm has been updated byKamel Didan and a new code is currently beingbaselined at MODAPS.

EVI and Blue ReflectanceSDS

MOD13A2.A2000081.h10v06.hdfTile ID

TM_MOD13A2Case No.

DOY 81-96

DOY 97-112

DOY 113-1281 km EVI Time Series

DOY 97-112

DOY 113-128

DOY 81-96

1 km NDVI Time Series

1km EVI Time Series

1km NDVI Time Series

South America

Description: A combined effect of a small numberof orbits (observations) and frequent cloud covercreates spatial discontinuities in the composite VIimages.

NDVI, EVI, and View Zenith AngleSDS

MOD13A2.A2000065.h11v10.hdfTile ID

TM_MOD13A2Case No.

MOD13A2: No. Orbits and Cloud CoverNDVI

View ZenithAngle

MODIS - AVHRR Comparisons

✷ NDVI Continuity♦ narrower ‘red’ MODIS band with increased

chlorophyll sensitivity (band 1),

♦ narrower ‘NIR’ MODIS band with less watervapor absorption (band 2)

AVHRR NDVI 2 week, 1km Compositemid-March 2000

USGS, EDC

1 kmNDVI

VI Comparisons (MODIS & AVHRR)

-0.30 -0.15 0.00 0.15 0.30 0.45 0.60

EVI

0.75

0.60

0.45

0.30

NDVI 0.15

0.00

-0.15

-0.30

Grassland - Foresttransition with MODISdata

MODIS Standard VI ProductsMOD 13A1

500 m and 16-day

✷ Normalized Difference Vegetation Index(NDVI)

✷ Enhanced Vegetation Index (EVI)

✷ Quality Analysis (QA) Image

Global NDVI at 500 mDOY 113-128

MOD13A1 QA

500m

500 m South America

Forest Clearcutting

NDVI 1 km/16 DaysTile No.: h20v11

View Zenith Angle (Degree*100)

-6000 -4000 -2000 0 2000 4000 6000

% F

requency

0

1

2

3

4MODISCVMVCMVC

17.2%

NDVI 1km/16 DaysTile No: h20v11

NDVI

-2000 0 2000 4000 6000 8000 10000

% F

requency

0.0

0.5

1.0

1.5

2.0

2.5MODISCVMVCMVC

EVI 1km/16 DaysTile No: h20v11

EVI

-2000 0 2000 4000 6000 8000 10000

% F

requency0

1

2

3

4

NDVI 1km/16 DaysTile No: h20v11

NDVI

-2000 0 2000 4000 6000 8000 10000

% F

requency

0.0

0.5

1.0

1.5

2.0

2.5MODISCVMVCMVC

EVI 1km/16 DaysTile No: h20v11

EVI

-2000 0 2000 4000 6000 8000 10000

% F

requency

0

1

2

3

4

NDVI 1km/16 DaysTile No: h20v11

NDVI

-2000 0 2000 4000 6000 8000 10000

% F

requency

0.0

0.5

1.0

1.5

2.0

2.5MODISCVMVCMVC

EVI 1km/16 DaysTile No: h20v11

EVI

-2000 0 2000 4000 6000 8000 10000

% F

requency

0

1

2

3

4

Conclusions

• VI performance coming along well

• Most problems are diminishing

• More work needed on compositingalgorithm and merging with cloud mask

• Need to investigate snow problem in EVI

• Aerosol resistance and VI saturation haveyet to be determined

Alaska