植生指数 (VGI)
[DOI: 10.57746/EO.01gs73b3y17efdvmj1ajftbfr2]

概要

NDVI, EVI 定義 植生の被覆や活性などを示す指数：NDVIとEVI
単位 無次元
ATBD Ver.1 (Nov. 2018)
SDI 定義 スペクトル情報を用いた植生の陰影の割合を示す指数
単位 無次元
ATBD Ver.1 (Sep. 2014)
Ver.2 (May 2020)
Ver.3 (Oct. 2021)

Ver2での変更点

  • ・カゲ指数計算のパラメータ修正
  • ・QAフラグ変更

Ver3での変更点

  • ・斜面法線からの太陽入射角余弦[Cosine_of_solar_incidence]をGeometry_dataに追加
  • ・SDI計算パラメータ、計算条件変更
  • ・QA_flag変更

サンプル画像

ファイル形式 Ver.1 Ver.2 Ver.3
hdf5 TBU
 VGI_Q(250m)
 VGI_Q(250m)
Image TBU
 EVI(250m)
NDVI(250m)
SDI(250m)
 EVI(250m)
NDVI(250m)
SDI(250m)

格納物理量

Ver.1,2,3 Description
EVI Enhanced Vegetation Index
NDVI Normalized Difference Vegetation Index
QA_flag
SDI Shadow Index

QA_flag情報

Ver.1 Ver.2 Ver.3 Ver.1(Sample Image) Ver.2(Sample Image) Ver.3(Sample Image)

Bit Data name Description EVI_L3_mask* NDVI_L3_mask* SDI_L3_mask*
0 no data 1: VN08 and/or VN11 are error 1 1 1
1 land/water 0: water >50%, 1: land > 50% 0 0 0
2 mixed with land/water 1: land and water > 1% 0 0 0
3 cloud 1: cloud 1 1 1
4 probably cloud 1: probably cloud 0 0 0
5 snow or ice 1: snow or ice 0 0 0
6 no data for EVI 1: no data for EVI 0 0 0
7 no data for SDI 1: no data for SDI 0 0 1
8 bad input for SW 1: bad input for SW 0 0 1
9 bad input for VN 1: bad input for VN 1 0 0
10 solar zenith angle >70 1: sza > 70° 1 1 0
11 sensor zenith angle >45 1: vza > 45° 0 0 0
12 EVI <-0.2 or EVI >1.0 1: EVI < -0.2 or 1.0 < EVI 1 0 0
13 large incident angle 1: cos(incident angle) < 0.1 0 0 0
14 small NDVI 1: NDVI < 0.65 0 0 0
15 anti solar side 1: anti solar side 0 0 0

 * 1は統計処理時にマスクされるBitを意味します。

 QA_flagについてはこちらをご参照ください。

Bit Data name Description EVI_L3_mask* NDVI_L3_mask* SDI_L3_mask*
0 no data 1: VN08 and/or VN11 are error 1 1 1
1 land/water 0: water >50%, 1: land > 50% 0 0 0
2 mixed with land/water 1: land and water > 1% 0 0 0
3 cloud 1: cloud 1 1 1
4 probably cloud 1: probably cloud 0 0 0
5 snow or ice 1: snow or ice 0 0 0
6 shadow 1: shadow 1 1 0
7 bad input for NDVI 1: bad input for NDVI 0 1 0
8 bad input for SDI 1: bad input for SDI 0 0 1
9 bad input for EVI 1: bad input for EVI 1 0 0
10 solar zenith angle >70 1: sza > 70° 1 1 0
11 sensor zenith angle >30 1: vza > 30° 0 0 0
12 EVI <-0.2 or EVI >1.0 1: EVI < -0.2 or 1.0 < EVI 1 0 0
13 large incident angle 1: cos(incident angle) < 0.1 0 0 0
14 small NDVI 1: NDVI < 0.65 0 0 0
15 anti solar side 1: anti solar side 0 0 0

 * 1は統計処理時にマスクされるBitを意味します。

 QA_flagについてはこちらをご参照ください。

Bit Data name Description EVI_L3_mask* NDVI_L3_mask* SDI_L3_mask*
0 no data 1: VN08 and/or VN11 are error 1 1 1
1 land/water 0: water >50%, 1: land > 50% 0 0 0
2 mixed with land/water 1: land and water > 1% 0 0 0
3 cloud 1: cloud 1 1 1
4 probably cloud 1: probably cloud 0 0 0
5 snow or ice 1: snow or ice 0 0 0
6 shadow 1: shadow 1 1 0
7 bad input for NDVI 1: bad input for NDVI 0 1 0
8 bad input for SDI 1: bad input for SDI 0 0 1
9 bad input for EVI 1: bad input for EVI 1 0 0
10 solar zenith angle >70 1: sza > 70° 1 1 0
11 sensor zenith angle >30 1: vza > 30° 0 0 0
12 EVI <-0.2 or EVI >1.0 1: EVI < -0.2 or 1.0 < EVI 1 0 0
13 large incident angle 1: cos(incident angle) < 0.1 0 0 0
14 small NDVI 1: NDVI < 0.75 0 0 0
15 anti solar side 1: anti solar side 0 0 0

 * 1は統計処理時にマスクされるBitを意味します。

 QA_flagについてはこちらをご参照ください。

*Download:QA_flag(Ver1) Sample Image

Attribute情報

Ver.1 Ver.2,3

Data name Attribute Remarks
Attribute of Image_data
Attribute of Image_data Grid_interval 0.002083333 250m: 0.002083333
Grid_interval_unit deg
Image_projection EQA (sinusoidal equal area) projection from 0-deg longitude
Number_of_pixels 4800 250m: 4800
Number_of_lines 4800
EVI
EVI
16-bit unsigned integer		 Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 30000
Slope 0.0001
Offset -1
Spatial_resolution 0.002083333 250m: 0.002083333
Data_description Enhanced Vegetation Index (EVI)
Unit NA
Spatial_resolution_unit degree
Mask_for_statistics 5641 詳細: QA_flag情報(～L3_mask)
NDVI
NDVI
16-bit unsigned integer		 Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 20000
Slope 0.0001
Offset -1
Spatial_resolution 0.002083333 250m: 0.002083333
Data_description Normalized Difference Vegetation Index (NDVI)
Unit NA
Spatial_resolution_unit degree
Mask_for_statistics 1033 詳細: QA_flag情報(～L3_mask)
SDI
SDI
16-bit unsigned integer		 Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 10000
Slope 1
Offset 0
Spatial_resolution 0.002083333 250m: 0.002083333
Data_description Shadow Index (SI)
Unit NA
Spatial_resolution_unit degree
Mask_for_statistics 393 詳細: QA_flag情報(～L3_mask)
Ver2,3 Attribute Remarks
Attribute of Image_data
Attribute of Image_data Grid_interval 0.002083333 250m: 0.002083333
Grid_interval_unit deg
Image_projection EQA (sinusoidal equal area) projection from 0-deg longitude
Number_of_pixels 4800 250m: 4800
Number_of_lines 4800
EVI
EVI
16-bit unsigned integer		 Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 30000
Slope 0.0001
Offset -1
Spatial_resolution 0.002083333 250m: 0.002083333
Data_description Enhanced Vegetation Index (EVI)
Unit NA
Spatial_resolution_unit degree
Mask_for_statistics 5705 詳細: QA_flag情報(～L3_mask)
NDVI
NDVI
16-bit unsigned integer		 Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 20000
Slope 0.0001
Offset -1
Spatial_resolution 0.002083333 250m: 0.002083333
Data_description Normalized Difference Vegetation Index (NDVI)
Unit NA
Spatial_resolution_unit degree
Mask_for_statistics 1225 詳細: QA_flag情報(～L3_mask)
SDI
SDI
16-bit unsigned integer		 Error_DN 65535
Minimum_valid_DN 0
Maximum_valid_DN 10000
Slope 1
Offset 0
Spatial_resolution 0.002083333 250m: 0.002083333
Data_description Shadow Index (SI)
Unit NA
Spatial_resolution_unit degree
Mask_for_statistics 265 詳細: QA_flag情報(～L3_mask)

使い方

  • ・物理量=DN*slope+offset
  • ・有効値はMinimum_valid_DN～Maximum_valid_DN