Project Details
Projekt
HAI PolWise, Employment of the HAI-TDLAS Hygrometer for the POLSTRACC and WISE missions on HALO
Applicant
Professor Dr. Volker Ebert
Subject Area
Atmospheric Science
Term
from 2016 to 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 316868214
The new multi-phase TDLAS hygrometer HAI has successfully demonstrated its unique capabilities over the past 4 years in many science missions (TACTS/ESMVAL/ML-CIRRUS/ACRIDICON), instrument intercomparisons and stringent metrological validations. During ML-Cirrus HAI demonstrated the first simultaneous airborne detection of total (ice + gas) and gas-phase water with a single instrument and a unique temporal resolution of over 120 Hz. In ACRIDICON-CHUVA HAI realized, in a new configuration, synchronous open- and closed-path gas-phase detection with improved gas exchange times, e.g. to study sampling artefacts. Up to day, HAI has an excellent, almost 100% reliability with more than 300 flight hours and more than 300.000 flight kilometers. In parallel HAI was stringently validated at the primary German water standards at PTB and compared to the most important airborne hygrometers in the Aquavit-II campaign. This ensures a well-defined absolute accuracy and creates an unprecedented link between Metrology and Meteorology, connecting all airborne campaigns, Aquavit-II and the international water vapor scale to each other. The current proposal will enable participation in the upcoming POLSTRACC and WISE missions, which require highly accurate and spatially highly resolved gas phase water detection and measurement of the core flight parameter relative humidity. The project also aims at further improvements of the HAI instrument, in particular faster evaluation algorithms. Currently HAI can be seen as a core instrument for in-situ measurements on HALO, as many essential scientific topics are directly linked a better understanding of the dynamics and spatial distribution of water vapor in the UTLS. HAI is the only instrument which can provide a spatial resolution down to 30 cm at 800 km/h cruising speed which allows a variety of new studies to be realized.
DFG Programme
Infrastructure Priority Programmes
