For details, see the Google Developers Site Policies. Setting the asFloat parameter to true, to get un-scaled, un-shifted floatĮxcept as otherwise noted, the content of this page is licensed under the Creative Commons Attribution 4.0 License, and code samples are licensed under the Apache 2.0 License. Output is Kelvin minus 100, to fit in the 8-bit range. That by default, reflective band output is reflectance scaled to 8-bits and thermal band Note that the input to the simple composite is a collection of raw imagery. Load a raw Landsat scene and display it. Radiance and TOA reflectance for a Landsat 8 image: The following example shows conversion from raw data to USGS site for Landsat 8) for more information about computing TOA reflectance orīrightness temperature. The TOA method converts thermal bands to brightness temperature. The TOA conversion is handled by the ee.() Linear transformation that accounts for solar elevation and seasonally variable Earth-Sunĭistance. Conversion to TOA (or at-sensor) reflectance is a Linear transformation using coefficients stored in scene metadataĪl. The conversion of DNs to at-sensor radiance is a The ‘raw’ scenes in Earth Engine contain imagery with digital numbers (DNs) that Surface reflectance (SR), cloud score and cloud-free composites. There are methods to compute at-sensor radiance, top-of-atmosphere (TOA) reflectance, See the Data Catalog'sĮarth Engine contains a variety of Landsat specific processing methods. Pre-Collection 1: no longer being produced by USGS, unmaintained byĮarth Engine, still available in Earth Engine but will eventually be purged.Ĭollection 1: produced by USGS until, maintained byĬollection 2: primary collection produced by USGS, increasing productĪvailability in Earth Engine as ingestion backlog is processed. Landsat 7, Enhanced Thematic Mapper Plus (ETM+) Replace 'LC08' in the above collectionĭefinitions with IDs from the following table to retrieve collections for the various These data exist for Landsat 4, 5, 7, and 8. Landsat 8, Collection 1, Tier 2 only, SR (no LST) Landsat 8, Collection 1, Tier 2 only, TOA Landsat 8, Collection 2, Tier 1 only, SR, and LST Landsat 8, Collection 1, Tier 1 only, TOA Landsat 8, Collection 1, Tier 1 + Real Time, TOA The collection ID for TOA and SR/LST collections using Landsat 8 data as an example. Reflectance), SR (surface reflectance), and LST (land surface temperature) products are offered. InĪddition, for each collection that contains T1 or T2 images, TOA (top-of-atmosphere To removals or potentially mis-registered scenes, you might want to stick to the T1Ĭollection, but in general, it's very uncommon that any misregistration is large enough toĮach of the above collections contains the raw data (i.e., scaled, at-sensor radiance). Reprocessed and categorized as either T1 or T2, it will be removed from the T1_RT collectionĪnd the new version will be added to the appropriate collection(s). Newly acquired scenes are added to the T1_RT collection daily. Landsat 8, Collection 1, Tier 1 + Real Time Grouped the scenes into collections by tier and satellite. To allow access to both the validated T1 data and the newest real-time data together, we've USGS documentation on Collection 1 Tiers for more information.
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