Landsat Level-2

Jointly managed by NASA and the USGS, Landsat is the longest running spaceborne earth imaging and observation program in history. Landsat Collection 2 Level-2 science products, imagery from 1982 to present, are made publicly available by the USGS. The continuity in this scientific record allows for critical and reliable observation and analysis of Earth processes and changes over time. This imagery layer provides global Landsat 4, 5, 7, 8, and 9 imagery. The layer is time-enabled and includes a number of predefined processing templates for visualization and analysis. Key Properties Geographic Coverage: Global landmasses Temporal Coverage: August 22, 1982 to present Spatial Resolution: 30-meter Revisit Time: ~8-days Product Level: Collection 2 Level-2 Science Products (Surface Reflectance and Surface Temperature) Source Data Coordinate System: Universal Transverse Mercator (UTM) WGS84 Service Coordinate System: Web Mercator Auxiliary Sphere WGS84 (EPSG:3857) Analysis: Analysis-Optimized Multispectral Bands: Band Description Wavelength* (µm) Spatial Resolution (m) 1 Coastal aerosol** 0.43 - 0.45 30 2 Blue 0.45 - 0.52 30 3 Green 0.52 - 0.60 30 4 Red 0.63 - 0.69 30 5 NIR 0.76 - 0.90 30 6 SWIR 1 1.55 - 1.75 30 7 SWIR 2 2.08 - 2.35 30 8 Pixel QA NA 30 9 Surface Temperature (Kelvin) 10.4-12.5 30*** 10 Surface Temperature QA NA 30 *This is the max range for each band based on the combined missions. For reference to the distinct ranges for each mission see this document. **Coastal Aerosol is only available from Landsat 8 and 9. For Landsat 4, 5, and 7 this band is simply a place holder and does not contain data. ***The thermal band is acquired at 100 or 120 meter resolution and resampled to 30 meters. Learn more about the Quality Assessment (QA) Bands Usage Information and Best Practices Processing Templates This layer includes a number of preconfigured processing templates (raster function templates) to provide on-the-fly data rendering and calculations for visualization and analysis. Each processing template includes labels and descriptions to characterize the intended usage. This may include for visualization, for analysis, or for both visualization and analysis. Visualization The default rendering on this layer is Natural Color (bands 4,3,2) for Visualization. There are a number of on-the-fly renderings/processing templates designed specifically for data visualization. By default, the most recent and most cloud free scenes from the Landsat archive are prioritized and dynamically fused into a single mosaicked image layer. To discover and isolate specific images for visualization in Map Viewer, try using the Image Collection Explorer. Analysis In order to leverage the optimization for analysis, the capability must be enabled by your ArcGIS organization administrator. More information on enabling this feature can be found in the ‘Regional data hosting’ section of this help doc. Optimized for analysis means this layer does not have size constraints for analysis and it is recommended for multisource analysis with other layers optimized for analysis. See this group for a complete list of imagery layers optimized for analysis. Using the "None" processing template option as input to analysis provides all bands with raw pixel values and is recommended for many use cases. Otherwise, only processing templates that include a "for analysis" designation should be used as input to analysis. The appropriate scale and offset, as recommended by USGS, is dynamically applied to the imagery in this layer, providing scientific floating point Surface Reflectance and Surface Temperature pixel values. Prior to running analysis, users should always provide some form of data selection with either a layer filter (e.g. for a specific date range, cloud cover percent, mission, etc.) or by selecting specific images. To discover and isolate specific images for analysis in Map Viewer, try using the Image Collection Explorer. General If you are new to Landsat imagery, the Landsat Explorer provides a good introductory user experience for working with this imagery layer. For more information, see this Quick Start Guide or this Detailed Tutorial. Data Source Landsat imagery is credited to the United States Geological Survey (USGS) and the National Aeronautics and Space Administration (NASA). The imagery in this layer is sourced from the Microsoft Planetary Computer Open Data Catalog.由美国国家航空航天局（National Aeronautics and Space Administration, NASA）与美国地质调查局（United States Geological Survey, USGS）联合管理的陆地卫星（Landsat）项目，是史上持续时间最长的星载地球成像与观测计划。美国地质调查局（USGS）现已公开1982年至今的陆地卫星（Landsat）Collection 2 Level-2科学产品与影像数据。该科学记录的连续性，为地球过程与长期变化的关键可靠观测与分析提供了核心支撑。本影像图层覆盖Landsat 4、5、7、8及9号卫星的全球影像，支持时间维度检索，并内置多款预定义处理模板，用于可视化与分析工作。 关键属性 地理覆盖范围：全球陆地 时间覆盖范围：1982年8月22日至今 空间分辨率：30米 重访周期：约8天 产品级别：Collection 2 Level-2科学产品（地表反射率与地表温度） 源数据坐标系：通用横轴墨卡托（Universal Transverse Mercator, UTM）WGS84 服务坐标系：Web墨卡托辅助球体WGS84（EPSG:3857） 分析优化多光谱波段： 1 海岸气溶胶**：波长0.43-0.45μm，空间分辨率30m 2 蓝光波段：波长0.45-0.52μm，空间分辨率30m 3 绿光波段：波长0.52-0.60μm，空间分辨率30m 4 红光波段：波长0.63-0.69μm，空间分辨率30m 5 近红外（NIR）波段：波长0.76-0.90μm，空间分辨率30m 6 短波红外1（SWIR 1）：波长1.55-1.75μm，空间分辨率30m 7 短波红外2（SWIR 2）：波长2.08-2.35μm，空间分辨率30m 8 像素质量评估（QA）波段：无有效波长数据，空间分辨率30m 9 地表温度（开尔文）波段：波长10.4-12.5μm，空间分辨率30m*** 10 地表温度质量评估（QA）波段：无有效波长数据，空间分辨率30m * 此为所有任务组合的波段最大波长范围，各卫星任务的专属波段范围请参阅对应文档。 ** 海岸气溶胶波段仅在Landsat 8和9号卫星中可用，Landsat 4、5及7号卫星的该波段仅为占位符，无有效数据。 *** 热红外波段原始分辨率为100米或120米，后重采样至30米。 有关质量评估（QA）波段的使用说明与最佳实践，请参阅相关文档。 处理模板 本图层内置多款预配置处理模板（栅格函数模板），可实现实时数据渲染与可视化、分析计算。每款模板均附带标签与用途说明，可分别用于可视化、分析或两者兼顾。 可视化 本图层默认渲染方式为自然色彩（使用4、3、2波段）。另有多款专为数据可视化设计的实时渲染/处理模板。默认情况下，系统优先选用陆地卫星档案中最新且云量最少的影像，并动态拼接为单一镶嵌影像图层。若需在地图查看器中查找并筛选特定影像用于可视化，可使用影像集合浏览器（Image Collection Explorer）。 分析 若需使用分析优化功能，需由您所在的ArcGIS组织管理员启用该能力，相关启用说明可参阅本文档"区域数据托管"章节。分析优化意味着本图层无分析尺寸限制，推荐与其他分析优化的影像图层进行多源分析。完整的分析优化影像图层列表可参阅此群组页面。 若选择"无"处理模板作为分析输入，将保留所有波段的原始像素值，适用于多数应用场景；除此之外，仅可选用标注为"用于分析"的处理模板作为分析输入。 系统将根据美国地质调查局（USGS）推荐的参数动态应用合适的缩放与偏移，为影像提供科学级浮点型地表反射率与地表温度像素值。 在开展分析前，用户需始终通过图层过滤器（例如指定特定日期范围、云量百分比、卫星任务等）或选择特定影像进行数据筛选。若需在地图查看器中查找并筛选特定影像用于分析，可使用影像集合浏览器。 通用说明 若您初次接触陆地卫星影像，陆地卫星浏览器（Landsat Explorer）可提供良好的入门使用体验。更多信息请参阅《快速入门指南》与《详细教程》。 数据源 本图层的影像数据由美国地质调查局（USGS）与美国国家航空航天局（NASA）提供授权，数据来源为微软行星计算机（Microsoft Planetary Computer）开放数据目录。