Stratospheric DIAL system Maido 6 channels and 3 signal pairs of - - PowerPoint PPT Presentation

6 channels and 3 signal pairs of absorbed/non absorbed wavelength 4 rayleigh pairs and 2 raman pairs

Stratospheric DIAL system Maido

nO3(z) ozone number density at altitude z P(λi,z) number of detected photons at wavelength λI ΔσO3(z) corresponds to the differential ozone absorption cross-section σO3(λ1,z) - σO3(λ2,z) δnO3(z) correction term depending on absorption by other constituents and Rayleigh and Mie differential Extinction Pbi is the background number of photon at wavelength λi,

DIAL METHOD

TREATEMENT

• the lidar signals (individual file of 3 min) are time-

averaged over the whole measurement period (3 h in general) increase the signal-to-noise ratio.

• Background correction
• Correction of the saturation of the photon

counting signals in the lower altitudes.

• Correction from the Rayleigh extinction using

composite pressure–temperature profiles from daily radiosoundings at gillot airport and model.

Typical resolution and precision