Contents
What is the difference between top of the atmosphere TOA reflectance and surface reflectance?
Top-of-atmosphere reflectance (or TOA reflectance) is the reflectance measured by a space-based sensor flying higher than the earth’s atmosphere. These reflectance values will include contributions from clouds and atmospheric aerosols and gases. Surface Reflectance is the reflectance of the surface of the Earth.
What is the altitude at the top of our atmosphere?
The exosphere is the outermost layer of Earth’s atmosphere (i.e. the upper limit of the atmosphere). It extends from the thermopause, at the top of the thermosphere at an altitude of about 700 km above sea level, to about 10,000 km (6,200 mi; 33,000,000 ft), where it merges into the solar wind.
How to convert Landsat OLI data to Toa reflectance?
Manually Converting Landsat 8 OLI data to ToA Reflectance: These data can be converted to ToA Reflectance using rescaling factors and parameters found in the metadata file (MTL.txt) provided with the data. The formulas and detailed explanations can be found on the USGS site: Using the USGS Landsat 8 Product .
How does the Landsat Collection 1 surface reflectance work?
The Landsat 4-7 Collection 1 Surface Reflectance Product Guide contains details about the LEDAPS algorithm and the Surface Reflectance data products created from it. While both the LEDAPS and LaSRC algorithms produce similar SR products, the inputs and methods to do so differ between them. The table below displays each algorithm.
How is the Landsat Level 1 data product rescaled?
Landsat Collections Level-1 data can be rescaled to top of atmosphere (TOA) reflectance and/or radiance using radiometric rescaling coefficients provided in the metadata file that is delivered with the Level-1 product. The metadata file also contains the thermal constants needed to convert thermal band data to TOA brightness temperature.
Where can I find scene based Landsat data?
Scene-based Surface Reflectance data (on-demand): Processing requests for scene-based Landsat Surface Reflectance data can be submitted from EarthExplorer. The data are located under the Landsat category, Landsat Collection 1 Level-2 (On-Demand)subcategory, with Landsat 8, Landsat 7, and Landsat 4-5 TM listed as individual datasets.