SAGE III on ISS role in climate processes. water vapor measurements will provide important contributions on the long-term effect of this green house gas. Ozone research has remained at the forefront of atmospheric science for many years because stratospheric ozone shields the Earth's surface (and its inhabitants) from harmful ultraviolet radiation. Since recent declines in stratospheric ozone have been linked to human activity, accurate long-term measurements of ozone remain crucial. It is important to monitor ozone levels in the lower stratosphere and upper troposphere since observed trends are the largest and most poorly understood at those altitudes. SAGE III's high vertical resolution and long-term
Non-ionizing radiation damage. Using ionizing radiation requires elaborate radiological protection measures which in general are not required with nonionizing radiation. The region at which radiation becomes considered as "ionizing" is not well defined, since different molecules and atoms ionize at different energies. The usual definitions have suggested that radiation with particle or photon energies less than 10 electronvolts (eV) be considered non-ionizing. Another suggested threshold is 33 electronvolts, which is the energy needed to ionize water molecules. The light from the Sun that reaches the earth is largely composed of non-ionizing radiation, since the ionizing far-ultraviolet rays have been filtered out by