A mobile differential absorption lidar for simultaneous observations of tropospheric and stratospheric ozone over Tibet

We developed a mobile ozone differential absorption lidar system to simultaneously measure the vertical profiles of tropospheric and stratospheric ozone from an altitude of ~5 to 50 km. The system emits four laser beams at wavelength of 289 nm, 299 nm, 308 nm and 355 nm and receives their corresponding Mie/Rayleigh backscattering return signals, and two N₂ Raman return signals at 332 nm and 387 nm shifted from 308 nm and 355 nm, respectively. An assembled telescope array with four 1.25-m telescopes (effective diameter > 2 m) collects the Rayleigh and Raman backscattering signals at 308/332 and 355/387 nm. This system is currently deployed at the Yangbajing Observatory in Tibet (~4300 m elevation) and has begun observations in regular campaign mode since October 2017. The lidar results agree very well with those observed by the Aura/MLS satellite. This novel ozone lidar system operates at the highest elevation of any such system in the world. The higher elevation and larger receiver aperture of this system yield a higher signal-to-noise ratio and lower statistical uncertainty.

Mobile lidar for simultaneous measurements of ozone, aerosols, and temperature in the stratosphere

A Meteorological Research Institute Mark II mobile lidar was developed for simultaneous measurements of ozone, temperature, and aerosols in the stratosphere. The lidar consists of an XeCl laser, a Nd:YAG laser, and an 80-cm diam receiving telescope. The laser beams at three wavelengths (308, 355, and 532 nm) can be almost simultaneously transmitted. The purpose of this lidar is to study, for example, the aerosol impact on the ozone layer through radiative and photochemical processes, the aerosol impact on the Umkehr measurements after violent volcanic eruptions, and the interaction between temperature and ozone. The performance of the lidar system and some data about ozone, aerosols, and temperature are described.

Evaluation of the solar-blind effect in ultraviolet ozone lidar with Raman lasers

Performances of differential absorption ozone lidars with ultraviolet Raman lasers are evaluated by a numerical simulation taking into account the solar-blind effect of stratospheric ozone for daytime observation; they are compared with observations. Calculations predict an ozone density profile up to 5 km in altitude determined during daylight using first and second Stokes lines of H(2), and up to 30 km at night using second Stokes line of CH(4) or D(2), and second and third Stokes lines of H(2) pumped by a KrF laser. A preliminary experiment of the daytime observations and a nighttime result are briefly reported.

Error analysis of DIAL measurements of ozone by a Shuttle excimer lidar

An error analysis of DIAL (differential absorption lidar) measurements of stratospheric ozone from the Space Shuttle is discussed. A transmitter system consisting of a KrF excimer laser pumping gas cells of H2 or D2 producing output wavelengths in the near UV is shown to be useful for the measurement of ozone in a 15-50-km altitude range.

Measurements of density and temperature profiles in the middle atmosphere with a XeF lidar

Density and temperature profiles in the 30-70-km altitude range are measured with a XeF lidar system using Rayleigh scattering. With a 16-W XeF laser at wavelengths 351 and 353 nm, density and temperature accuracies of less than +/-3% and +/-10 K are obtained up to 60 km for an observation time of 15 min. The overall performances are now competitive with and superior to those of traditional Nd:YAG SHG lidars at 532 nm.