The atmospheric molecule density profile is directly derived from the correction-range lidar signal. The temperature profile is deduced from the molecular density profile based on the assumptions of the hydrostatic equilibrium and the ideal-gas law. Lidar measurements show good agreement with the molecular density and the temperature profiles from the MSISE-90 atmospheric model. Maximum errors of the density and temperature are found to be ± and ± K, respectively. The position and the temperature of the stratopause in Hanoi are determined to be about 49 km and 270 K. | Communications in Physics, Vol. 24, No. 3 (2014), pp. 247-256 DOI: MEASUREMENTS OF THE STRATOSPHERIC DENSITY AND TEMPERATURE PROFILES IN HANOI BY A RAYLEIGH LIDAR NGUYEN XUAN TUAN, DINH VAN TRUNG, NGUYEN THANH BINH Institute of Physics, Vietnam Academy of Science and Technology BUI VAN HAI Le Quy Don Technical University E-mail: nxtuan@ Received 24 February 2014 Accepted for publication 04 April 2014 doi: 3690 Abstract. The molecular density and temperature profiles of the stratosphere in Hanoi are measured by a Rayleigh lidar. The profiles have the spatial resolution of 120 m and the temporal resolution of 1h. Their bottom height and top height are 20 km and 57 km, respectively. The atmospheric molecule density profile is directly derived from the correction-range lidar signal. The temperature profile is deduced from the molecular density profile based on the assumptions of the hydrostatic equilibrium and the ideal-gas law. Lidar measurements show good agreement with the molecular density and the temperature profiles from the MSISE-90 atmospheric model. Maximum errors of the density and temperature are found to be ± and ± K, respectively. The position and the temperature of the stratopause in Hanoi are determined to be about 49 km and 270 K. Database of lidar in a long time might reveal the characteristic and the structure of the stratosphere in Hanoi, Vietnam. I. INTRODUCTION The stratosphere, an atmospheric layer located between about 15 km to 50 km, has strongly interested in scientific community in some recent decades because it plays an important role to weather and climate in the synoptic and global scales [1] The stratosphere might directly affects to climate in the synoptic and global scales through: atmospheric planetary wave, atmospheric gravity wave, tide, jet stream . . . Variations of the stratosphere affect also on climate of the troposphere and surface layers through processes: coupling and .