Google Earth Engine ——LANDSAT 7 Collection 1 Tier 1 and Real-Time data DN values数据集

Landsat 7 Collection 1 Tier 1 and Real-Time data DN values, representing scaled, calibrated at-sensor radiance.

Landsat scenes with the highest available data quality are placed into Tier 1 and are considered suitable for time-series processing analysis. Tier 1 includes Level-1 Precision Terrain (L1TP) processed data that have well-characterized radiometry and are inter-calibrated across the different Landsat sensors. The georegistration of Tier 1 scenes will be consistent and within prescribed tolerances [<=12 m root mean square error (RMSE)]. All Tier 1 Landsat data can be considered consistent and inter-calibrated (regardless of sensor) across the full collection. See more information in the USGS docs.

The T1_RT collection contains both Tier 1 and Real-Time (RT) assets. Newly-acquired Landsat 7 ETM+ and Landsat 8 OLI/TIRS data are processed upon downlink but use predicted ephemeris, initial bumper mode parameters, or initial TIRS line of sight model parameters. The data is placed in the Real-Time tier and made available for immediate download. Once the data have been reprocessed with definitive ephemeris, updated bumper mode parameters and refined TIRS parameters, the products are transitioned to either Tier 1 or Tier 2 and removed from the Real-Time tier. The transition delay from Real-Time to Tier 1 or Tier 2 is between 14 and 26 days.For more information, see

Landsat 7 Collection 1 Tier 1和Real-Time数据DN值，代表按比例、校准的传感器辐射度。

具有最高可用数据质量的陆地卫星场景被归入第1级，并被认为适合进行时间序列处理分析。第一级包括一级精确地形（L1TP）处理过的数据，这些数据具有良好的辐射测量特性，并在不同的陆地卫星传感器之间进行了相互校准。第1级场景的地理注册将是一致的，并在规定的公差范围内[<=12米均方根误差（RMSE）]。所有第1级Landsat数据都可以被认为是一致的，并且在整个集合中进行了相互校准（不管是哪个传感器）。参见USGS文档中的更多信息。

T1_RT集合包含一级和实时（RT）资产。新获得的Landsat 7 ETM+和Landsat 8 OLI/TIRS数据在下行时被处理，但使用预测的星历、初始碰击模式参数或初始TIRS视线模型参数。这些数据被放在实时层，可供立即下载。一旦用确定的星历、更新的保险杠模式参数和完善的TIRS参数对数据进行重新处理，产品就会过渡到1级或2级，并从实时层中删除。从实时到第1级或第2级的过渡延迟为14至26天。

Dataset Availability

1999-01-01T00:00:00 - 2021-09-20T00:00:00

Dataset Provider

USGS

Collection Snippet

ee.ImageCollection("LANDSAT/LE07/C01/T1_RT")

Bands Table

影像属性：

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确认或信用，应通过包括一行文字引用来提供，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：

var dataset = ee.ImageCollection('LANDSAT/LE07/C01/T1')
                  .filterDate('1999-01-01', '2002-12-31');
var trueColor321 = dataset.select(['B3', 'B2', 'B1']);
var trueColor321Vis = {};
Map.setCenter(6.746, 46.529, 6);
Map.addLayer(trueColor321, trueColor321Vis, 'True Color (321)');