Google Earth Engine ——Landsat 7 影像集合数据集详细介绍

Landsat 7

Landsat 7 collection.

Surface Reflectance

  • USGS Landsat 7 Surface Reflectance Tier 1

  • USGS Landsat 7 Surface Reflectance Tier 2

Top of Atmosphere (TOA)

  • USGS Landsat 7 Collection 1 Tier 1 TOA Reflectance

  • USGS Landsat 7 Collection 1 Tier 1 and Real-Time data TOA Reflectance

  • USGS Landsat 7 Collection 1 Tier 2 TOA Reflectance

Raw Images

  • USGS Landsat 7 Collection 1 Tier 1 Raw Scenes

  • USGS Landsat 7 Collection 1 Tier 1 and Real-Time data Raw Scenes

  • USGS Landsat 7 Collection 1 Tier 2 Raw Scenes

Derived Datasets

  • Burned Area Index (BAI)

  • Enhanced Vegetation Index (EVI)

  • Normalized Difference Vegetation Index (NDVI)

  • Normalized Burn Ratio Thermal (NBRT)

  • Normalized Difference Snow Index (NDSI)

  • Normalized Difference Water Index (NDWI)

Specifications and Quality

Section 5 of the Landsat 4-7 Collection 1 (C1) Surface Reflectance Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) product guide provides information related to the SR specifications as well to the data quality measurements.

Surface Reflectance Specifications

Table 7 Landsat 4-7 Surface Reflectance Specifications

Band Designation

Band Name

Data Type

Units

Range

Valid Range

Fill Value

Saturate Value

Scale Factor

ProductID_sr_band1

Band 1

16-Bit Signed Integer

Reflectance

-2000 - 16000

0 - 10000

-9999

20000

0.0001

ProductID_sr_band2

Band 2

16-Bit Signed Integer

Reflectance

-2000 - 16000

0 - 10000

-9999

20000

0.0001

ProductID_sr_band3

Band 3

16-Bit Signed Integer

Reflectance

-2000 - 16000

0 - 10000

-9999

20000

0.0001

ProductID_sr_band4

Band 4

16-Bit Signed Integer

Reflectance

-2000 - 16000

0 - 10000

-9999

20000

0.0001

ProductID_sr_band5

Band 5

16-Bit Signed Integer

Reflectance

-2000 - 16000

0 - 10000

-9999

20000

0.0001

ProductID_sr_band6

Band 6

16-Bit Signed Integer

Reflectance

-2000 - 16000

0 - 10000

-9999

20000

0.0001

ProductID_sr_band7

Band 7

16-Bit Signed Integer

Reflectance

-2000 - 16000

0 - 10000

-9999

20000

0.0001

ProductID_sr_atmos_opacity

Atmospheric Opacity

16-Bit Signed Integer

Unitless

-2000 - 16000

0 - 10000

-9999

NA

0.0010

ProductID_pixel_qa

Level 2 Quality Band

16-Bit Unsigned Integer

Bit Index

0 - 32768

0 - 32768

1 (Bit 0)

NA

NA

ProductID_radsat_qa

Radiometric Saturation QA

16-Bit Unsigned Integer

Bit Index

0 - 32768

0 - 32768

1 (Bit 0)

NA

NA

ProductID_sr_cloud_qa

Surface Reflectance Cloud QA

8-Bit Unsigned Integer

Bit Index

0 - 255

0 - 63

NA

NA

NA

ProductID_MTL.txt

Level 1 Metadata File

NA

NA

NA

NA

NA

NA

NA

ProductID_ANG.txt

Level 1 Angle Coefficient File

NA

NA

NA

NA

NA

NA

NA

Surface Reflectance Cloud Quality Assessment Band

Table 8 Landsat 4-7 Surface Reflectance Cloud Quality Assessment Bit Index

Bit

Attribute

0

Dark Dense Vegetation (DDV)

1

Cloud

2

Cloud Shadow

3

Adjacent to Cloud

4

Snow

5

Water

6

Unused

7

Unused

Table 9 Landsat 4-7 Surface Reflectance Cloud Quality Assessment Values

Attribute

Pixel Value

DDV

1, 9

Cloud

2, 34

Cloud Shadow

4, 12, 20, 36, 52

Adjacent to Cloud

8, 12, 24, 40, 56

Snow

16, 20, 24, 48, 52, 56

Water

32, 34, 36, 40, 48, 52, 56

Pixel Quality Assessment Band

Table 10 Landsat 4-7 Pixel Quality Assessment Bit Index

Bit

Bit Value

Cumulative Sum

Attribute

0

1

1

Fill

1

2

3

Clear

2

4

7

Water

3

8

15

Cloud Shadow

4

16

31

Snow

5

32

63

Cloud

6-7

64 / 128

127 / 255

Cloud Confidence
00 (0) = None
01 (1) = Low
10 (2) = Medium
11 (3) = High

8

256

511

Unused

9

512

1023

Unused

10

1024

2047

Unused

11

2048

4095

Unused

12

4096

8191

Unused

13

8192

16383

Unused

14

16384

32767

Unused

15

32768

65535

Unused

Table 11 Landsat 4-7 Pixel Quality Assessment Values

Attribute

Pixel Value

Fill

1

Clear

66, 130

Water

68, 132

Cloud Shadow

72, 136

Snow/Ice

80, 112, 144, 176

Cloud

96, 112, 160, 176, 224

Low Confidence Cloud

66, 68, 72, 80, 96, 112

Medium Confidence Cloud

130, 132, 136, 144, 160, 176

High Confidence Cloud

224

Radiometric Saturation Quality Assessment Band

Table 12 Landsat 4-7 Radiometric Saturation Quality Assessment Bit Index

Bit

Bit Value

Cumulative Sum

Description

0

1

1

Data Fill Flag (0 valid data, 1 invalid data)

1

2

3

Band 1 Data Saturation Flag (0 valid data, 1 saturated data)

2

4

7

Band 2 Data Saturation Flag (0 valid data, 1 saturated data)

3

8

15

Band 3 Data Saturation Flag (0 valid data, 1 saturated data)

4

16

31

Band 4 Data Saturation Flag (0 valid data, 1 saturated data)

5

32

63

Band 5 Data Saturation Flag (0 valid data, 1 saturated data)

6

64

127

Band 6 Data Saturation Flag (0 valid data, 1 saturated data)

7

128

255

Band 7 Data Saturation Flag (0 valid data, 1 saturated data)

8

NA

NA

Not Used