SUMMARYA new set of laboratory measurements of the 1.06 ¹m and 1.27 ¹m collision-induced bands of gaseous oxygen is presented. Absorption by pure oxygen and mixtures of oxygen with nitrogen and argon was observed using a Fourier transform spectrometer for temperatures between 230 and 295 K and pressures between 1 and 5 bar. Binary cross-sections derived from the measurements were used to estimate the impacts on estimates of clearsky climatological absorption of solar irradiance. Monthly climatological atmospheric pro les averaged over 10

These two cases increase the total short-wave absorption by the atmosphere by between 0.4 and i %. They contribute to resolving the discrepancy between observed and modelled short-wave absorption and indicate a need for the spectral data for other near-infrared and visible bands of water vapour to be re-examined.

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We characterized the white-light supercontinuum emission by a sub-petawatt laser system in the atmosphere via light detection and ranging measurements. As much as 1 J of supercontinuum is generated in the atmosphere, corresponding to a conversion efficiency of 30 %. This generation occurs at altitudes below 100 m. The high initial beam intensity results in the saturation of the number of self-guided filaments. Therefore, the “photon bath” surrounding the filaments strongly contributes to the white-light generation. These finding is well reproduced by numerical simulations based on the experimental parameters