Starting March 30, 2017, users will be able to request processing of Landsat Higher-Level (Surface Reflectance) data for Landsat 4-8 Collection 1 scenes from EarthExplorer, as shown in the graphic below.
Users are encouraged to review the March 17, 2017 news item and consult the Product Guides provided on that page for more information about the many differences between Pre-Collection and Collection 1 Higher-Level data products.
Sources/Usage: Public Domain.