Supporting data and model code for the EPSL article "Revisiting oxygen isotope anomalies in NO₂ and nitrate in the nocturnal atmosphere: a modeling approach"

This repository contains the model code and supporting data for the study "Revisiting oxygen isotope anomalies in NO₂ and nitrate in the nocturnal atmosphere: a modeling approach", published in Earth and Planetary Science Letters (EPSL). Contents: Isotope-explicit box model code (in python) used to simulate nocturnal Δ¹⁷O transfer in NOₓ chemistry under different model senarios. Data files contained Hefei winter observations from Zhang et al. (2025) EST article to compare with model ouput. Plot scripts and produced figures are also included in each script. These materials are provided to ensure full reproducibility of the findings and to facilitate further research on NOx and nitarte oxygen isotope tracing in atmospheric chemistry. Users are encouraged to cite the associated EPSL article when using this model.