Quality assessment of an open-path tuneable diode laser spectrometer for water vapour measurement and scientific studies during first HALO demo missions

• Applicants: Professor Dr. Volker Ebert; Dr. Martina Krämer, since 6/2012
• Subject Area: Atmospheric Science
• Term: from 2007 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 48779895

After the development of the diode laser hygrometer HAI for deployment onboard HALO in the 1stSPP phases, we here propose its deployment during four upcoming scientific missions: TACTS/SALSA, Cirrus-ML, Cirrus-RS and POLSTRACC. The planned frequent deployment requires thedevelopment of new fast data retrieval algorithms. A focus will further be a strong quality controlof HAI and other HALO hygrometers, embedded in international programs lead by SPARC, in orderto make the HALO water data, (i.e. total water, gas phase water, and ice water content) compatiblewith those from other national and international missions. They include validation againstPTB standards, the organization of and participation in an international validation campaign forhygrometers at the AIDA chamber of KIT, in-flight intercomparison with other instruments on HALOand further platforms, and the development of internationally accepted standards for calibrationprocedures and new in-flight calibration equipment. The data obtained during the missionswill be analyzed with statistical methods to compile a water distribution in the extra tropical UTLSand its seasonal variability. Simulations with the CLaMS model of FZJ will be made towards acomprehensive theoretical understanding of dynamical processes in the UTLS with a focus on thetropopause inversion layer.

• DFG Programme: Infrastructure Priority Programmes
• Subproject of: SPP 1294: Atmospheric and Earth System Research with the "High Altitude and Long Range Research Aircraft" (HALO)
• Participating Person: Dr. Paul Konopka
• Ehemaliger Antragsteller: Dr. Cornelius Schiller, until 6/2012 (†)