Ground-level nitrogen dioxide concentration estimates for 2021-2025 around Gyeongbuk wildfire in 2025

This dataset provides daily, gridded estimates of surface nitrogen dioxide (NO₂) concentrations over the study region in South Korea (35.9–37.0°N, 127.9–129.4°E) from 1 January 2021 to 31 December 2025, at a spatial resolution of 0.05° × 0.05°. Surface NO₂ concentrations were estimated by calibrating TROPOspheric Monitoring Instrument (TROPOMI) tropospheric NO₂ column observations against ground-based air-quality measurements using a linear mixed-effects model. Ground-based measurements at 13:00 and 14:00 were averaged for each date and grid cell to construct the calibration data. The model included fixed effects, day-specific random intercepts and slopes, and a grid-level variance component. The released estimates were calculated using the fixed effects and day-specific random intercepts and slopes. They therefore represent satellite-derived surface NO₂ estimates calibrated to early-afternoon observations, rather than 24-hour mean concentrations. The CSV file contains 851,113 records across 660 grid cells. Each record identifies a date, the latitude and longitude of the grid-cell center, and the estimated surface NO₂ concentration in parts per billion (ppb). Missing estimates are represented by empty fields (19,974 records). Spatial and temporal coverage is incomplete, and the file does not contain every possible date–grid combination. Negative model estimates have been retained without truncation. Variable Description Unit / format datetime Date associated with the estimate YYYYMMDD lat Latitude of the grid-cell center Degrees north lon Longitude of the grid-cell center Degrees east NO2_estimated Estimated surface NO₂ concentration ppb