Data from: Integrating Carbonyl Sulfide and Solar-Induced Fluorescence Improves Estimation of Gross Primary Productivity in Rice Paddies

Accurate estimation of gross primary productivity (GPP) is fundamental for understanding ecosystem carbon cycling. Solar-induced chlorophyll fluorescence (SIF) and carbonyl sulfide (COS) provide complementary proxies of photosynthesis, yet their relative performance across temporal scales and sky conditions remains uncertain. Using continuous eddy covariance COS fluxes and ground-based SIF observations in a rice paddy, we assess their relationships with GPP at half-hourly and daily scales under clear and cloudy conditions. SIF shows stronger correlations with GPP at the half-hourly scale, whereas COS–GPP associations strengthen after temporal aggregation, particularly under cloudy skies. Partial correlations indicate that SIF captures short-term variability, while COS becomes more informative at the daily scale. Integrating SIF and COS improves GPP estimation across conditions, especially at the daily scale and under cloudy skies. These results demonstrate scale-dependent complementarity and highlight the value of multi-proxy approaches for robust ecosystem GPP estimation.