Hydrogen in the upper atmosphere



Over the last 4 years researchers in the United States have made important contributions to the noticeable improvement of our knowledge of hydrogen in the upper atmosphere.

In addition to new data being obtained in rocket, satellite, and ground-based measurements, improved interpretation of the data and understanding of background effects have lead to more reliable results on hydrogen abundances and diurnal and other variations. Theoretical and observational progress has been made in the understanding of the vertical profiles, the diurnal variations, and the nature of sources and sinks for hydrogen in the upper atmosphere. The effect of hydrogen escape on the evolution of oxygen in the earth's atmosphere has been reinterpreted.