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Title: Daily Cropland Soil NO x Emissions Identified by TROPOMI and SMAP
Abstract

We use TROPOMI (TROPOspheric Monitoring Instrument) tropospheric nitrogen dioxide (NO2) measurements to identify cropland soil nitrogen oxide (NOx = 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 NOxenhancements and estimate maximum cropland soil NOxemissions (15–34 ng N m−2 s−1) early in growing season (May–June). We observe soil NOxpulsing 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 NOxpulse events. This demonstrates that TROPOMI NO2observations, combined with observations of underlying process controls (e.g., soil moisture), can constrain soil NOxprocesses from space.

 
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Award ID(s):
1650682
NSF-PAR ID:
10375166
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
DOI PREFIX: 10.1029
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
47
Issue:
22
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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