A powerful lidar system capable of 1?h measurements of water vapour in the troposphere and the lower stratosphere as well as the temperature in the upper stratosphere and mesosphere

摘要

A high-power Raman lidar system has been installed at the high-altitude research station Schneefernerhaus (Garmisch-Partenkirchen, Germany) at 2675? m a . s . l . , at the side of an existing wide-range differential absorption lidar (DIAL). An industrial XeCl laser was modified for linearly polarized single-line operation at an average power of about 180? W . This high power and a 1.5? m diameter receiver allow us to extend the operating range for water-vapour sounding to 20? km for a measurement time of just 1?h, at an uncertainty level of the mixing ratio of 1 to 2? ppm . This was achieved for a vertical resolution varied between just 0.2 and 0.6? km in the stratosphere. The lidar was successfully validated with a balloon-borne cryogenic frost-point hygrometer (CFH). In addition, temperature measurements up to altitudes of around 87? km were demonstrated for 1?h of signal averaging. The system has been calibrated with the DIAL, the CFH and radiosondes.