A Raman lidar at La Reunion (20.8° S, 55.5° E) for monitoring water vapour and cirrus distributions in the subtropical upper troposphere: preliminary analyses and description of a future system
- 1LATMOS, UMR8190, INSU-CNRS – UVSQ, UPMC, 11 Boulevard d'Alembert, 78820 Guyancourt, France
- 2LACy, UMR8105, 15 avenue René Cassin, BP 7151, 97715 St-Denis Cedex 09, La Réunion, France
- 3Meteorological Observatory Lindenberg, Deutscher Wetterdienst, Am Observatorium 12, 15848 Lindenberg, Germany
- 4OSU Réunion, UMS3365, 15 avenue René Cassin, BP 7151, 97715 St-Denis Cedex 09, La Réunion, France
- *now at: LE2P, 15 avenue René Cassin, BP 7151, 97715 St-Denis Cedex 09, La Réunion, France
- **now at: LMD, UMR8539, INSU-CNRS, UPMC, Ecole Polytechnique, 91128 Palaiseau Cedex, France
Abstract. A ground-based Rayleigh lidar has provided continuous observations of tropospheric water vapour profiles and cirrus cloud using a preliminary Raman channels setup on an existing Rayleigh lidar above La Reunion over the period 2002–2005. With this instrument, we performed a first measurement campaign of 350 independent water vapour profiles. A statistical study of the distribution of water vapour profiles is presented and some investigations concerning the calibration are discussed. Analysis regarding the cirrus clouds is presented and a classification has been performed showing 3 distinct classes. Based on these results, the characteristics and the design of a future lidar system, to be implemented at the new Reunion Island altitude observatory (2200 m) for long-term monitoring, is presented and numerical simulations of system performance have been realised to compare both instruments.