Monthly Patterns of Ammonia Over the Contiguous United States at 2-km Resolution

Rui Wang, Xuehui Guo, Da Pan, James T. Kelly, Jesse O. Bash, Kang Sun, Fabien Paulot, Lieven Clarisse, Martin Van Damme, Simon Whitburn, Pierre François Coheur, Cathy Clerbaux, Mark A. Zondlo

Research output: Contribution to journalArticlepeer-review

18 Scopus citations


Monthly, high-resolution (∼2 km) ammonia (NH3) column maps from the Infrared Atmospheric Sounding Interferometer (IASI) were developed across the contiguous United States and adjacent areas. Ammonia hotspots (95th percentile of the column distribution) were highly localized with a characteristic length scale of 12 km and median area of 152 km2. Five seasonality clusters were identified with k-means++ clustering. The Midwest and eastern United States had a broad, spring maximum of NH3 (67% of hotspots in this cluster). The western United States, in contrast, showed a narrower midsummer peak (32% of hotspots). IASI spatiotemporal clustering was consistent with those from the Ammonia Monitoring Network. CMAQ and GFDL-AM3 modeled NH3 columns have some success replicating the seasonal patterns but did not capture the regional differences. The high spatial-resolution monthly NH3 maps serve as a constraint for model simulations and as a guide for the placement of future, ground-based network sites.

Original languageEnglish (US)
Article numbere2020GL090579
JournalGeophysical Research Letters
Issue number5
StatePublished - Mar 16 2021

All Science Journal Classification (ASJC) codes

  • Geophysics
  • General Earth and Planetary Sciences


  • IASI
  • ammonia
  • emissions
  • oversampling
  • satellite
  • seasonality


Dive into the research topics of 'Monthly Patterns of Ammonia Over the Contiguous United States at 2-km Resolution'. Together they form a unique fingerprint.

Cite this