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Abstract We use TROPOMI (TROPOspheric Monitoring Instrument) tropospheric nitrogen dioxide (NO₂) measurements to identify cropland soil nitrogen oxide (NO_x = NO + NO₂) emissions at daily to seasonal scales in the U.S. Southern Mississippi River Valley. Evaluating 1.5 years of TROPOMI observations with a box model, we observe seasonality in local NO_xenhancements and estimate maximum cropland soil NO_xemissions (15–34 ng N m⁻² s⁻¹) early in growing season (May–June). We observe soil NO_xpulsing in response to daily decreases in volumetric soil moisture (VSM) as measured by the Soil Moisture Active Passive (SMAP) satellite. Daily NO₂enhancements reach up to 0.8 × 10¹⁵ molecules cm⁻²4–8 days after precipitation when VSM decreases to ~30%, reflecting emissions behavior distinct from previously defined soil NO_xpulse events. This demonstrates that TROPOMI NO₂observations, combined with observations of underlying process controls (e.g., soil moisture), can constrain soil NO_xprocesses from space.