N: 90 S: -90 E: 180 W: -180
2.5 Decimal Degrees x 2 Decimal Degrees
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) and 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 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.
The EMIT Level 4 Earth System Model (EMITL4ESM) Version 1 data product provides radiative forcing outputs, along with other ancillary outputs generated from different Earth System Models (ESMs). ESMs are complex models that integrate relevant physical, chemical, biological, and human components to simulate multiple aspects of large-scale systems on Earth. Multiple models, input mineral maps, meteorology inputs, and emissions/concentration scenarios are examined for the model runs contained within this data product. Models currently utilized include the Community Earth System Model 2 (CESM2) and the Goddard Institute for Space Studies (GISS) model. Some ESM runs utilize reference surface mineral maps from the literature dating back to 2007; others rely on the EMIT L3 Aggregated Mineral Spectral Abundance and Uncertainty 0.5 Deg (EMITL3ASA) data as inputs.
Each EMITL4ESM granule represents a single ESM run with a Network Common Data Format 4 (netCDF-4) file for each variable. A total of 12 Science Dataset (SDS) layers or variables are provided for each model run. For some SDS layers or variables, multiple layers based on inclusion of model minerology inputs are provided in their netCDF files. The layers/variables table below details which variables contain the extra layers. Metadata flags for Earth System Model, Resolution, Surface Mineral Map, External Meteorology, Time Period, and Emissions/Concentration Scenario indicate the key parameters for each granule. A table outlining each variable in detail can be found in the EMIT Science Data System Level 4 repository.
Known Issues
Citation is critically important for dataset documentation and discovery. This dataset is openly shared, without restriction, in accordance with the EOSDIS Data Use and Citation Guidance.
Variables are a set of physical properties whose values determine the characteristics or behavior of something. For example, temperature and pressure are variables of the atmosphere. Parameters and variables can be used interchangeably. Variable level attributes provide individual information for each variable.
The Name in this table is the variable name. Fill value indicates missing or undefined data points in a variable. Valid range is the range of values the variable can store. Scale factor is used to increase or decrease the size of an object and can be used to correct for distortion. For questions on a specific variable, please use the Earthdata Forum.
| Name Sort descending | Description | Units | Data Type | Fill Value | Valid Range | Scale Factor |
|---|---|---|---|---|---|---|
| atmospheric_mineral_composition | Atmospheric mineral composition: this is an output of the ESM. Variable will be repeated for each model minerology, using the nomenclature “[basename]_[mineral]”, where basename is name of this variable. The [mineral] portion of the variable names will be one of the following: ill, kao, sme, feo, qua, cal, fel, gyp, Illi, Kaol, Smec, Calc, Quar, Feld, FeOx, Gyps, IlFe, KaFe, SmFe, CaFe, QuFe, FeFe, and GyFe. An explanation of these abbreviations can be found on the dataset landing page: https://doi.org/10.5067/EMIT/EMITL4ESM.001. | kg mineral/kg air | float32 | -9999 | N/A | N/A |
| dry_deposition | Dry dust deposition to the surface. Variable will be repeated for each model minerology, using the nomenclature “[basename]_[mineral]”, where basename is name of this variable. The [mineral] portion of the variable names will be one of the following: ill, kao, sme, feo, qua, cal, fel, gyp, Illi, Kaol, Smec, Calc, Quar, Feld, FeOx, Gyps, IlFe, KaFe, SmFe, CaFe, QuFe, FeFe, and GyFe. An explanation of these abbreviations can be found on the dataset landing page: https://doi.org/10.5067/EMIT/EMITL4ESM.001. | kg/m²/s | float32 | -9999 | N/A | N/A |
| dust_aod_vis | Dust aerosol optical depth averaged across the visible wavelength range. | N/A | float32 | -9999 | N/A | N/A |
| dust_lw_rf_sfc | Dust longwave radiative forcing at the surface. | W/m² | float32 | -9999 | N/A | N/A |
| dust_lw_rf_toa | Dust longwave radiative forcing at the top of atmosphere. | W/m² | float32 | -9999 | N/A | N/A |
| dust_ssa_vis | Dust single scattering albedo averaged across the visible wavelength range. | N/A | float32 | -9999 | N/A | N/A |
| dust_sw_rf_sfc | Dust shortwave radiative forcing at the surface. | W/m² | float32 | -9999 | N/A | N/A |
| dust_sw_rf_toa | Dust shortwave radiative forcing at the top of atmosphere. | W/m² | float32 | -9999 | N/A | N/A |
| input_mineral_fraction_emitted | Fractional emitted mineral composition; this is an input into the ESM. Variable will be repeated for each model minerology, using the nomenclature “[basename]_[mineral]”, where basename is name of this variable. The [mineral] portion of the variable names will be one of the following: ill, kao, sme, feo, qua, cal, fel, gyp, Illi, Kaol, Smec, Calc, Quar, Feld, FeOx, Gyps, IlFe, KaFe, SmFe, CaFe, QuFe, FeFe, and GyFe. An explanation of these abbreviations can be found on the dataset landing page: https://doi.org/10.5067/EMIT/EMITL4ESM.001. | N/A | float32 | -9999 | N/A | N/A |
| mod_min_soil_emis | Mineral soil emissions through time; this is an output of the ESM. Variable will be repeated for each model minerology, using the nomenclature “[basename]_[mineral]”, where basename is name of this variable. The [mineral] portion of the variable names will be one of the following: ill, kao, sme, feo, qua, cal, fel, gyp, Illi, Kaol, Smec, Calc, Quar, Feld, FeOx, Gyps, IlFe, KaFe, SmFe, CaFe, QuFe, FeFe, and GyFe. An explanation of these abbreviations can be found on the dataset landing page: https://doi.org/10.5067/EMIT/EMITL4ESM.001. | kg/m²/s | float32 | -9999 | N/A | N/A |
| surface_concentration_by_volume | Surface mineral concentration volume. Variable will be repeated for each model minerology, using the nomenclature “[basename]_[mineral]”, where basename is name of this variable. The [mineral] portion of the variable names will be one of the following: ill, kao, sme, feo, qua, cal, fel, gyp, Illi, Kaol, Smec, Calc, Quar, Feld, FeOx, Gyps, IlFe, KaFe, SmFe, CaFe, QuFe, FeFe, and GyFe. An explanation of these abbreviations can be found on the dataset landing page: https://doi.org/10.5067/EMIT/EMITL4ESM.001. | kg/m³ | float32 | -9999 | N/A | N/A |
| wet_deposition | Wet dust deposition to the surface. Variable will be repeated for each model minerology, using the nomenclature “[basename]_[mineral]”, where basename is name of this variable. The [mineral] portion of the variable names will be one of the following: ill, kao, sme, feo, qua, cal, fel, gyp, Illi, Kaol, Smec, Calc, Quar, Feld, FeOx, Gyps, IlFe, KaFe, SmFe, CaFe, QuFe, FeFe, and GyFe. An explanation of these abbreviations can be found on the dataset landing page: https://doi.org/10.5067/EMIT/EMITL4ESM.001. | kg/m²/s | float32 | -9999 | N/A | N/A |