Worldwide spatial and temporal ammonia (NH₃) variability revealed by IASI

Martin van Damme (1) , Lieven Clarisse (1) , Simon Whitburn (1) , Cathy Clerbaux (1, 2) , Pierre-François Coheur (1)

1 Spectroscopie de l'atmosphère, Service de Chimie Quantique et Photophysique
2 TROPO - LATMOS

As a short-lived species, ammonia (NH₃) is highly variable in time and space, and while ground based measurements are possible, they are sparse and their coverage is largely heterogeneous. Consequently, spatial and temporal patterns of NH₃ emissions and their strength are poorly known and account for the largest uncertainties in the nitrogen cycle. IASI is measuring since 8 years NH₃ columns at a high spatiotemporal resolution. The aim of this work is to assess distributions and to investigate, from a global to a local scale, the variability of NH₃ using this remarkable time series. We first look at yearly distributions (2008-2015) to identify the main source processes and areas. Seasonal patterns and inter-annual variability are then investigated at subcontinental scale by looking at global composite seasonal means and monthly time series over various regions around the world, considering separately but simultaneously measurements from IASI morning and evening overpasses. The relations between the NH₃ atmospheric abundance and emission processes is emphasized at smaller regional scale by extracting at high spatial resolution the global climatology of the month of maxima columns. Finally, IASI observations are exploited to identify and track industrial NH₃ emissions.

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

Martin van Damme, Lieven Clarisse, Simon Whitburn, Cathy Clerbaux, Pierre-François Coheur. Worldwide spatial and temporal ammonia (NH₃) variability revealed by IASI. 4th IASI International Conference, Apr 2016, Antibes Juan-Les-Pins, France. ⟨insu-01306201⟩