Absorption spectroscopy, which is widely used for concentration measurement
s of tropospheric and stratospheric compounds, requires precise values of t
he absorption cross-sections of the measured species. NO2, O-2 and its coll
ision-induced absorption spectrum, and H2O absorption cross-sections have b
een measured at temperature and pressure conditions prevailing in the Earth
's atmosphere. Corrections to the generally accepted analysis procedures us
ed to resolve the convolution problem are also proposed.