| Aerosol mass mixing ratio | 5 - marginal | Limited to high atmosphere.. Daylight only. | UV, VIS, NIR spectrometry | 
	| Atmospheric temperature | 4 - fair | Limited to high atmosphere.. Daylight only. | UV, VIS and NIR spectrometry at higher spectral resolution < 1.5 nm | 
	| BrO* | 3 - high | Limited to high atmosphere.. Daylight only. | UV spectrometry.  BrO lines around 300 nm.  Limb sounding mechanically or electronically | 
	| HCHO* | 3 - high | Limited to high atmosphere.. Daylight only. | UV spectrometry.  HCHO lines around 350 nm.  Limb sounding mechanically or electronically | 
	| ClO* | 3 - high | Limited to high atmosphere.. Daylight only. | UV Spectrometry.  ClO lines around 300 nm. | 
	| NO* | 4 - fair | Limited to high atmosphere.. Daylight only. | UV spectrometry.  NO lines around 250 nm. | 
	| NO2* | 4 - fair | Limited to high atmosphere.. Daylight only. | UV and VIS spectrometry.  Several lines in the ranges around 220 nm and 400 nm. | 
	| O3* | 4 - fair | Limited to high atmosphere.. Daylight only. | UV and VIS spectrometry.  Ozone lines in the bands around 260 nm (Hartley) and/or 340 nm (Huggins) and 600 nm (Chappuis). | 
	| PSC occurrence | 4 - fair | Limited to high atmosphere.. Daylight only. | UV and VIS spectrometry. | 
	| SO2* | 4 - fair | Limited to high atmosphere.. Daylight only. | UV spectrometry.  SO2 lines around 350 nm. | 
	| Specific humidity | 4 - fair | Limited to high atmosphere.. Daylight only. | UV, VIS and NIR spectrometry with several water vapour bands (main: around 940 nm). | 
	| Aerosol volcanic ash | 5 - marginal | Limited to high atmosphere.. Daylight only. | UV, VIS and NIR spectrometry; |