Excess atmospheric ammonia (NH3) leads to deleterious effects on biodiversity, ecosystems, air quality and health, and it is therefore essential to monitor its budget and temporal evolution.... Show moreExcess atmospheric ammonia (NH3) leads to deleterious effects on biodiversity, ecosystems, air quality and health, and it is therefore essential to monitor its budget and temporal evolution. Hyperspectral infrared satellite sounders provide daily NH3 observations at global scale for over a decade. Here we use the version 3 of the Infrared Atmospheric Sounding Interferometer (IASI) NH3 dataset to derive global, regional and national trends from 2008 to 2018. We find a worldwide increase of 12.8 ± 1.3 % over this 11-year period, driven by large increases in east Asia (5.80 ± 0.61 % increase per year), western and central Africa (2.58 ± 0.23 %.yr−1), North America (2.40 ± 0.45 %.yr−1) and western and southern Europe (1.90 ± 0.43 %.yr−1). These are also seen in the Indo-Gangetic Plain, while the southwestern part of India exhibits decreasing trends. Reported national trends are analyzed in the light of changing anthropogenic and pyrogenic NH3 emissions, meteorological conditions and the impact of sulfur and nitrogen oxides emissions, which alter the atmospheric lifetime of NH3. We end with a short case study dedicated to the Netherlands and the "Dutch Nitrogen crisis" of 2019. Show less
This work covers the evolution of satellite based Aeronautical Public Correspondence and the operational environment in which services are being offered. Followed by an examination of applicable... Show moreThis work covers the evolution of satellite based Aeronautical Public Correspondence and the operational environment in which services are being offered. Followed by an examination of applicable rules, including the relevant institutions from which they emanate, attention is devoted to questions on liability and the effect of State Sovereignty, applicable in territorial airspace, the Arctic, Antarctica, and the High Seas as well as, to activities such as telecommunications, air transport, copyright protection and trade in services. Particular attention is given to the ITU Radio Regulations; ITU Sector Recommendations; ICAO Council Regulations; International Copyright Laws; National Operational Procedures and Statutes. Show less