Global Ammonia Distribution Derived from Infrared Satellite Observations

Abstract

Over the past century there has been a steady increase in the global emission of ammonia entailing a host of environ-mental problems. There are large un-certainties in our understanding of ammonia levels on both temporal and spatial scales. Part of this is due to the dearth of ground based observations, their representativeness for larger scales, and virtual absence of meas-urements aloft. In this work we present the first local and global daily ammo-nia concentrations measured from the space borne thermal infrared spec-trometer IASI/MetOp. From the 2008 yearly average we identify high ammo-nia hotspots over the world¿s agricul-tural and biomass burning regions. We find an overall good qualitative agree-ment with a global model of the am-monia cycle. On average the measured concentrations are found to be lower than the modeled. However, large un-derestimations in the model fields are found at mid-latitudes in the Northern hemisphere.