Surface Ozone-Induced Yield Losses and Economic Costs of Winter Wheat Across China: Spatiotemporal Estimates Based on Reconstructed M7 and AOT40 Exposures (2015–2022)

Surface ozone (O3) adversely affects winter wheat production. However, due to the lack of spatially continuous ozone exposure datasets directly linked to crop yield responses, the assessment of ozone-induced crop losses remains uncertain. Winter wheat, a major food crop in China, is highly sensitive to ozone. Its primary cultivation region—the North China Plain (NCP)—overlaps with severe ozone pollution areas, creating significant risk asuperposition. To address this, we employed a spatiotemporal LightGBM (ST-LightGBM) model with ground observations, atmospheric reanalysis, and satellite retrievals to reconstruct a 10 km resolution dataset of daily 7 h average (M7) and daytime accumulated ozone exposure index (AOT40) across China from 2015 to 2022. The model performed robustly; SHAP analysis showed that downward solar radiation and 2 m temperature explained over 42% of ozone variability. From 2015 to 2022, despite pollution controls and the COVID-19 pandemic, surface ozone showed a phased upward trend (0.83 μg m−3 yr−1), with O3 concentrations increasing across 79.22% of the study area and the NCP most affected. Applying M7 and AOT40, the average annual relative yield loss of winter wheat ranged from 3.44% to 7.20% (M7) and from 26.50% to 36.54% (AOT40), corresponding to economic losses of 2.21–4.44 billion USD and 16.16–26.08 billion USD. Both metrics showed consistent trends, but AOT40 losses were substantially higher, highlighting the need to incorporate cumulative high-concentration exposure into agricultural risk assessments. These findings demonstrate that O3 pollution poses a substantial threat to winter wheat production in China. The reconstructed exposure metrics provide a quantitative basis for identifying high-risk agricultural regions and inform targeted mitigation strategies to safeguard food security under intensifying O3 pollution.