Google Earth Engine ——LANDSAT/LT04/C02/T1系列数据介绍!

2024-02-02 09:48:32 浏览数 (2)

This dataset contains atmospherically corrected surface reflectance and land surface temperature derived from the data produced by the Landsat TM sensor. These images contain 4 visible and near-infrared (VNIR) bands and 2 short-wave infrared (SWIR) bands processed to orthorectified surface reflectance, and one thermal infrared (TIR) band processed to orthorectified surface temperature. They also contain intermediate bands used in calculation of the ST products, as well as QA bands.

Landsat 4 and 5 SR products are created with the Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS) algorithm (version 3.4.0). All Collection 2 ST products are created with a single-channel algorithm jointly created by the Rochester Institute of Technology (RIT) and National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory (JPL).

Strips of collected data are packaged into overlapping "scenes" covering approximately 170km x 183km using a standardized reference grid.

Some assets have only SR data, in which case ST bands are present but empty. For assets with both ST and SR bands, 'L1_PROCESSING_LEVEL' is set to 'L2SP'. For assets with only SR bands, 'L1_PROCESSING_LEVEL' is set to 'L2SR'.

Additional documentation and usage examples.

Data provider notes:

  • Data products must contain both optical and thermal data to be successfully processed to surface temperature, as ASTER NDVI is required to temporally adjust the ASTER GED product to the target Landsat scene. Therefore, night time acquisitions cannot be processed to surface temperature.
  • A known error exists in the surface temperature retrievals relative to clouds and possibly cloud shadows. The characterization of these issues has been documented by Cook et al., (2014).

该数据集包含从Landsat TM传感器产生的数据中提取的大气校正表面反射率和地表温度。这些图像包含4个可见光和近红外(VNIR)波段和2个短波红外(SWIR)波段,被处理成正射的表面反射率,以及一个热红外(TIR)波段,被处理成正射的表面温度。它们还包含用于计算ST产品的中间波段,以及QA波段。

Landsat 4和5的SR产品是用Landsat Ecosystem Disturbance Adaptive Processing System (LEDAPS)算法(3.4.0版)制作的。所有的2号卫星产品都是用罗切斯特理工学院(RIT)和美国国家航空航天局(NASA)喷气推进实验室(JPL)联合创建的单通道算法创建的。

收集的数据条被打包成重叠的 "场景",使用标准化的参考网格,覆盖大约170公里x183公里。

一些资产只有SR数据,在这种情况下,ST波段是存在的,但却是空的。对于既有ST波段又有SR波段的资产,"L1_PROCESSING_LEVEL "被设置为 "L2SP"。对于只有SR带的资产,'L1_PROCESSING_LEVEL'被设置为'L2SR'。

其他文件和使用例子。

数据提供者说明。

数据产品必须包含光学和热数据,才能成功处理成表面温度,因为ASTER NDVI需要在时间上调整ASTER GED产品与目标Landsat场景。因此,夜间采集的数据不能被处理成地表温度。

在相对于云和可能的云影的表面温度检索中存在一个已知的错误。库克等人(2014)已经记录了这些问题的特征。

Dataset Availability

1982-08-22T00:00:00 - 1993-12-14T00:00:00

Dataset Provider

USGS

Collection Snippet

Copied

ee.ImageCollection("LANDSAT/LT04/C02/T1_L2")

Resolution

30 meters

Bands Table

Name

Description

Min

Max

Units

Wavelength

Scale

Offset

SR_B1

Band 1 (blue) surface reflectance

1

65455

0.45-0.52 μm

0.0000275

-0.2

SR_B2

Band 2 (green) surface reflectance

1

65455

0.52-0.60 μm

0.0000275

-0.2

SR_B3

Band 3 (red) surface reflectance

1

65455

0.63-0.69 μm

0.0000275

-0.2

SR_B4

Band 4 (near infrared) surface reflectance

1

65455

0.77-0.90 μm

0.0000275

-0.2

SR_B5

Band 5 (shortwave infrared 1) surface reflectance

1

65455

1.55-1.75 μm

0.0000275

-0.2

SR_B7

Band 7 (shortwave infrared 2) surface reflectance

1

65455

2.08-2.35 μm

0.0000275

-0.2

ST_B6

Band 6 surface temperature.

0

65535

Kelvin

10.40-12.50 μm

0.00341802

149

SR_ATMOS_OPACITY

A general interpretation of atmospheric opacity generated by LEDAPS and based on the radiance viewed over Dark Dense Vegetation (DDV) within the scene. A general interpretation of atmospheric opacity is that values (after scaling by 0.001 is applied) less than 0.1 are clear, 0.1-0.3 are average, and values greater than 0.3 indicate haze or other cloud situations. SR values from pixels with high atmospheric opacity will be less reliable, especially under high solar zenith angle conditions. The SR_ATMOS_OPACITY band is provided for advanced users and for product quality assessment and has not been validated. Most users are advised to instead use the QA_PIXEL band information for cloud discrimination.

0

10000

0.001

0

SR_CLOUD_QA

Cloud Quality Assessment

0

0

SR_CLOUD_QA Bitmask

Bit 0: Dark Dense Vegetation (DDV)Bit 1: CloudBit 2: Cloud ShadowBit 3: Adjacent to CloudBit 4: SnowBit 5: Water

ST_ATRAN

Atmospheric Transmittance.

0

10000

0.0001

0

ST_CDIST

Pixel distance to cloud.

0

24000

km

0.01

0

ST_DRAD

Downwelled Radiance.

0

28000

W/(m^2*sr*um)/ DN

0.001

0

ST_EMIS

Emissivity estimated from ASTER GED.

0

10000

0.0001

0

ST_EMSD

Emissivity standard deviation.

0

10000

0.0001

0

ST_QA

Uncertainty of the Surface Temperature band.

0

32767

K

0.01

0

ST_TRAD

Thermal band converted to radiance.

0

22000

W/(m^2*sr*um)/ DN

0.001

0

ST_URAD

Upwelled Radiance.

0

28000

W/(m^2*sr*um)/ DN

0.001

0

QA_PIXEL

Pixel quality attributes generated from the CFMASK algorithm.

0

0

QA_PIXEL Bitmask

Bit 0: FillBit 1: Dilated CloudBit 2: UnusedBit 3: CloudBit 4: Cloud ShadowBit 5: SnowBit 6: Clear 0: Cloud or Dilated Cloud bits are set1: Cloud and Dilated Cloud bits are not setBit 7: WaterBits 8-9: Cloud Confidence 0: None1: Low2: Medium3: HighBits 10-11: Cloud Shadow Confidence 0: None1: Low2: Medium3: HighBits 12-13: Snow/Ice Confidence 0: None1: Low2: Medium3: HighBits 14-15: Cirrus Confidence 0: None1: Low2: Medium3: High

QA_RADSAT

Radiometric saturation QA

0

0

QA_RADSAT Bitmask

Bit 0: Band 1 data saturatedBit 1: Band 2 data saturatedBit 2: Band 3 data saturatedBit 3: Band 4 data saturatedBit 4: Band 5 data saturatedBit 5: Band 6L data saturatedBit 6: Band 7 data saturatedBit 7: UnusedBit 8: Band 6H data saturatedBit 9: Dropped pixel 0: Pixel present1: Detector doesn't have a value

  • Bit 0: Dark Dense Vegetation (DDV)
  • Bit 1: Cloud
  • Bit 2: Cloud Shadow
  • Bit 3: Adjacent to Cloud
  • Bit 4: Snow
  • Bit 5: Water

ST_ATRANAtmospheric Transmittance.0100000.00010ST_CDISTPixel distance to cloud.024000km0.010ST_DRADDownwelled Radiance.028000W/(m^2*sr*um)/ DN0.0010ST_EMISEmissivity estimated from ASTER GED.0100000.00010ST_EMSDEmissivity standard deviation.0100000.00010ST_QAUncertainty of the Surface Temperature band.032767K0.010ST_TRADThermal band converted to radiance.022000W/(m^2*sr*um)/ DN0.0010ST_URADUpwelled Radiance.028000W/(m^2*sr*um)/ DN0.0010QA_PIXELPixel quality attributes generated from the CFMASK algorithm.00QA_PIXEL Bitmask

  • Bit 0: Fill
  • Bit 1: Dilated Cloud
  • Bit 2: Unused
  • Bit 3: Cloud
  • Bit 4: Cloud Shadow
  • Bit 5: Snow
  • Bit 6: Clear
    • 0: Cloud or Dilated Cloud bits are set
    • 1: Cloud and Dilated Cloud bits are not set
  • Bit 7: Water
  • Bits 8-9: Cloud Confidence
    • 0: None
    • 1: Low
    • 2: Medium
    • 3: High
  • Bits 10-11: Cloud Shadow Confidence
    • 0: None
    • 1: Low
    • 2: Medium
    • 3: High
  • Bits 12-13: Snow/Ice Confidence
    • 0: None
    • 1: Low
    • 2: Medium
    • 3: High
  • Bits 14-15: Cirrus Confidence
    • 0: None
    • 1: Low
    • 2: Medium
    • 3: High

QA_RADSATRadiometric saturation QA00QA_RADSAT Bitmask

  • Bit 0: Band 1 data saturated
  • Bit 1: Band 2 data saturated
  • Bit 2: Band 3 data saturated
  • Bit 3: Band 4 data saturated
  • Bit 4: Band 5 data saturated
  • Bit 5: Band 6L data saturated
  • Bit 6: Band 7 data saturated
  • Bit 7: Unused
  • Bit 8: Band 6H data saturated
  • Bit 9: Dropped pixel
    • 0: Pixel present
    • 1: Detector doesn't have a value

影像属性:

Name

Type

Description

ALGORITHM_SOURCE_SURFACE_REFLECTANCE

String

Name and version of the surface reflectance algorithm.

ALGORITHM_SOURCE_SURFACE_TEMPERATURE

String

Name and version of the surface temperature algorithm.

CLOUD_COVER

Double

Percentage cloud cover (0-100), -1 = not calculated.

CLOUD_COVER_LAND

Double

Percentage cloud cover over land (0-100), -1 = not calculated.

COLLECTION_CATEGORY

String

Scene collection category, "T1" or "T2".

DATA_SOURCE_AIR_TEMPERATURE

String

Air temperature data source.

DATA_SOURCE_ELEVATION

String

Elevation data source.

DATA_SOURCE_OZONE

String

Ozone data source.

DATA_SOURCE_PRESSURE

String

Pressure data source.

DATA_SOURCE_REANALYSIS

String

Reanalysis data source.

DATA_SOURCE_WATER_VAPOR

String

Water vapor data source.

DATE_PRODUCT_GENERATED

Double

Timestamp of the date when the product was generated.

EARTH_SUN_DISTANCE

Double

Earth-Sun distance (AU).

EPHEMERIS_TYPE

Identifier to inform the user of the orbital ephemeris type used: "DEFINITIVE" or "PREDICTIVE". If the field is not present, the user should assume "PREDICTIVE".

GEOMETRIC_RMSE_MODEL

Double

Combined RMSE (Root Mean Square Error) of the geometric residuals (meters) in both across-track and along-track directions.

GEOMETRIC_RMSE_MODEL_X

Double

RMSE (Root Mean Square Error) of the geometric residuals (meters) measured on the GCPs (Ground Control Points) used in geometric precision correction in the across-track direction.

GEOMETRIC_RMSE_MODEL_Y

Double

RMSE (Root Mean Square Error) of the geometric residuals (meters) measured on the GCPs (Ground Control Points) used in geometric precision correction in the along-track direction.

GROUND_CONTROL_POINTS_MODEL

Double

Number of GCPs used in the precision correction process. This parameter is only present if the PROCESSING_LEVEL is L1TP.

GROUND_CONTROL_POINTS_VERSION

Double

GCP dataset version used in the precision correction process. This parameter is only present if the PROCESSING_LEVEL is L1TP.

IMAGE_QUALITY

Int

Composite image quality for the bands. 0 = worst, 9 = best, -1 = quality not calculated or assessed.

L1_DATE_PRODUCT_GENERATED

String

Product generation date for the corresponding L1 product.

L1_LANDSAT_PRODUCT_ID

String

Landsat Product Identifier for the corresponding L1 product.

L1_PROCESSING_LEVEL

String

Processing Level for the corresponding L1 product.

L1_PROCESSING_SOFTWARE_VERSION

String

Processing software version for the corresponding L1 product.

LANDSAT_PRODUCT_ID

String

Landsat Product Identifier

LANDSAT_SCENE_ID

String

Short Landsat Scene Identifier

PROCESSING_LEVEL

String

"L2SP" when both SR and LST bands are present, or "L2SR" when only SR bands are present.

PROCESSING_SOFTWARE_VERSION

String

The processing software version that created the product.

SCENE_CENTER_TIME

String

Time of the observations as in ISO 8601 string.

SENSOR_ID

String

Name of the sensor.

SPACECRAFT_ID

String

Name of the spacecraft.

SUN_AZIMUTH

Double

Sun azimuth angle in degrees for the image center location at the image center acquisition time. A positive value indicates angles to the east or clockwise from the north. A negative value indicates angles to the west or counterclockwise from the north.

SUN_ELEVATION

Double

Sun elevation angle in degrees for the image center location at the image center acquisition time. A positive value indicates a daytime scene. A negative value indicates a nighttime scene. Note: For reflectance calculation, the sun zenith angle is needed, which is 90 - sun elevation angle.

TEMPERATURE_MAXIMUM_BAND_ST_B6

Double

Maximum achievable temperature value for Band 6.

TEMPERATURE_MINIMUM_BAND_ST_B6

Double

Minimum achievable temperature value for Band 6.

WRS_PATH

Int

WRS path number of scene.

WRS_ROW

Int

WRS row number of scene.

使用说明:

Landsat datasets are federally created data and therefore reside in the public domain and may be used, transferred, or reproduced without copyright restriction.

Acknowledgement or credit of the USGS as data source should be provided by including a line of text citation such as the example shown below.

(Product, Image, Photograph, or Dataset Name) courtesy of the U.S. Geological Survey

Example: Landsat-7 image courtesy of the U.S. Geological Survey

See the USGS Visual Identity System Guidance for further details on proper citation and acknowledgement of USGS products.

Landsat数据集是联邦创建的数据,因此属于公共领域,可以在没有版权限制的情况下使用、转让或复制。

对美国地质调查局作为数据来源的鸣谢或信用,应包括一行文字的引用,如下面的例子。

(产品、图像、照片或数据集名称)由美国地质调查局提供。

例子。Landsat-7图像由美国地质调查局提供

请参阅美国地质调查局视觉识别系统指南,了解有关美国地质调查局产品的正确引用和鸣谢的进一步细节。

代码:

代码语言:javascript复制
var dataset = ee.ImageCollection('LANDSAT/LT04/C01/T1_TOA')
                  .filterDate('1989-01-01', '1992-12-31');
var trueColor321 = dataset.select(['B3', 'B2', 'B1']);
var trueColor321Vis = {
  min: 0.0,
  max: 0.4,
  gamma: 1.2,
};
Map.setCenter(6.746, 46.529, 6);
Map.addLayer(trueColor321, trueColor321Vis, 'True Color (321)');

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