For the first time, researchers have discovered ammonia in the Earth's lowest atmospheric layer with highest emissions of the gas encountered in North India and Southeast China. Scientists of Karlsruhe Institute of Technology (KIT) in Germany together with researchers from US and Mexico analysed satellite measurements by the MIPAS infrared spectrometer and found increased amounts of ammonia (NH3) between 12 and 15 km height in the area of the Asian monsoon.

This suggests that the gas is responsible for the formation of aerosols, smallest particles that might contribute to cloud formation, researchers said. Ammonia, a chemical compound of nitrogen and hydrogen, mainly originates from agricultural processes, in particular from life-stock farming and fertilisation.

Highest ammonia emissions are encountered in North India and Southeast China. Due to population growth and global warming, global ammonia emissions are expected to increase strongly in the future, researchers said. Gaseous ammonia reacts with acids, such as sulfuric acid or nitric acid, to the corresponding ammonium salts. However, ammonia does not only pollute the ecosystems. Ammonia isn't the only unexpected gas scientists have detected in Earth's atmosphere recently - a type of hot atomic hydrogen atom has also been found in an upper layer of Earth's atmosphere - and our current understanding of physics says they shouldn't be able to exist here.

The findings will hopefully give scientists a better basis on which to build their global climate models, and the German team plans to continue modelling the atmospheric ammonia above China and India throughout 2017.