Daily 24-hour Average Nitrogen Dioxide (NO2) Concentrations over California (0.01° × 0.01°), 1980-2022

This dataset contains daily 24-hour average NO2 concentrations (ppb) in California at 0.01° × 0.01° spatial resolution, estimated by integrating a priori NO2 information from chemical transport model simulations, publicly available geospatial predictors, and a deep learning algorithm. The modeling framework demonstrated robust performance across the study period (1980–2022), with grid-based 10-fold cross-validation R2 values ranging from 0.72 to 0.83 against in-situ observations.