EMIT L2B Fractional Cover and Uncertainty 60 m V001

The Earth Surface Mineral Dust Source Investigation (EMIT) instrument measures surface mineralogy, targeting the Earth’s arid dust source regions. EMIT is installed on the International Space Station (ISS). EMIT uses imaging spectroscopy to take measurements of the sunlit regions of interest between ~52° N latitude and ~52° S latitude. An interactive map showing the locations of regions being investigated, current and forecasted data coverage, and additional data resources can be found on the VSWIR Imaging Spectroscopy Interface for Open Science (VISIONS) [EMIT Open Data Portal](https://earth.jpl.nasa.gov/emit/data/data-portal/coverage-and-forecasts/).

The EMIT Level 2B Fractional Cover and Uncertainty (EMITL2BFRCOV) Version 1 data product provides a series of fractional cover estimates, associated uncertainty metrics, and one quality control (QC) flag mask variable. The fractional cover estimates are derived from the EMIT L2A Estimated Surface Reflectance and Uncertainty and Masks ([EMITL2ARFL](https://doi.org/10.5067/EMIT/EMITL2ARFL.001)) data product, while the QC flag mask variable is derived from EMITL2ARFL, EMIT L2A Mask ([EMITL2AMASK](https://doi.org/10.5067/EMIT/EMITL2AMASK.002)), and non-EMIT landcover and water body inputs. Scenes/granules where cloud cover is greater than 80 percent have been excluded from this collection. For more details about inputs used for this data product, see Sections 4.3 and 4.5 of the Algorithm Technical Basis Document ([ATBD](https://github.com/emit-sds/emit-sds-frcov/blob/main/docs/EMIT_L2B_Fractional_Cover_ATBD.md)).

Each EMITL2BFRCOV granule consists of seven Cloud Optimized GeoTIFF (COG) files at 60 meter (m) spatial resolution: Photosynthetic Vegetation Fractional Cover (EMIT_L2B_FRCOVPV) and Uncertainty (EMIT_L2B_FRCOVPVUNC), Non-photosynthetic Vegetation Fractional Cover (EMIT_L2B_FRCOVNPV) and Uncertainty (EMIT_L2B_FRCOVNPVUNC), Bare Soil Fractional Cover (EMIT_L2B_FRCOVBARE) and Uncertainty (EMIT_L2B_FRCOVBAREUNC), and QC Flags (EMIT_L2B_FRCOVQC). A browse image is also available.

Each granule is approximately 75 kilometers (km) by 75 km, nominal at the equator with some granules at the end of an orbit segment reaching 150 km in length.

Known Issues
• Data acquisition gap: From September 13, 2022, to January 6, 2023, a power issue resulted in a shutdown of the EMIT sensor. No data were acquired during that time frame.