ECOSTRESS Gridded Weight Percent Silica L3 Global 0.01 Degree Map V001

The ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) mission acquires high-resolution thermal infrared (TIR) data on the Earth’s surface with five spectral bands in the 8-12.5 μm range. ECOSTRESS is attached to the International Space Station (ISS) and collects data globally between approximately 52° N and 52° S latitudes. The ECOSTRESS Gridded Weight Percent Silica L3 Global 0.01 Degree Map (ECO_L3G_WPS) Version 1 demonstrates the potential of TIR image data acquired by the ECOSTRESS sensor to produce the first mineral maps of the Earth’s arid and semi-arid regions. Weight Percent Silica (WPS) quantifies the weight percent of SiO₂ (silica) across exposed rocks, sand, and soil by detecting the spectral shift of the diagnostic Si–O vibrational feature. ECO_L3G_WPS was generated by averaging all clear-sky ECOSTRESS Level 2 Gridded emissivity [ECO_L2G_LSTE](https://doi.org/10.5067/ECOSTRESS/ECO_L2G_LSTE.003) pixels from 2023 to 2024 onto a 0.01° (~1 km) global grid, then applying the WPS algorithm. The source emissivity data and mapping approach were validated against known mineralogy at two arid sites (quartz and gypsum), using direct comparison of field-collected samples. The product contains one science variable: WPS, and is distributed as a single global GeoTIFF. Vegetated and ocean pixels are masked to Not a Number (NaN). Known Issues * Coverage restriction: Data are limited to arid and semi-arid regions as defined by the Global Land Data Assimilation System (GLDAS) aridity mask. Vegetated areas, permanent ice, and ocean pixels are masked and contain no valid data. * Fixed values at data extremes: Weight Percent Silica values of exactly 3.2509% and 91.4135% (approximately 5.3% of valid pixels) occur when a pixel's true spectral minimum cannot be resolved by the retrieval algorithm. Users performing quantitative analysis (e.g., means, histograms, correlations) should be aware that these two specific values do not represent precise surface retrievals.