Leipziger Meteorologisches Kolloquium
Dr. Sabrina Schnitt: Observing the Arctic water cycle using the Differential Absorption G-band Radar
In diesem Vortrag möchten wir Ihnen die Möglichkeit bieten, aktuelle Forschungsthemen und innovative Ansätze aus dem Bereich Arktische Verstärkung kennenzulernen. Unsere eingeladene Referentin wird seine neuesten Erkenntnisse und Projekte vorstellen, gefolgt von anregenden Diskussionen.
Observing the Arctic water cycle using the Differential Absorption G-band Radar GRaWAC
Referent: Dr. Sabina Schnitt
(Wissenschaftliche Mitarbeiterin an der Unvirsität zu Köln, Institut für Geophysik und Meteorologie)
The Arctic water cycle is rapidly changing in warming Arctic climate conditions. Continuous observations of the atmospheric state are not only key to monitoring occurring changes, but also to advancing the representation of the water cycle in Earth system models. Current state-of-the-art remote sensing techniques, yet, are challenged by the occurrence of clouds, precipitation, or polar night, and lack the needed temporal or vertical resolution. Cloud radars operating at a high frequency in the G-band can close some of these observational gaps. The high radar frequency promises increased sensitivity to small hydrometeors compared to conventional cloud radars operating in Ka- or W-band. When applying the newly emerging Differential Absorption Radar (DAR) technique to measurements at differently attenuated channels, continuous in-cloud water vapor profiles can be retrieved at a resolution of up to 250m.
We illustrate these advantages with recent measurements obtained from the novel and unique G-band Radar for Water vapor and Arctic Clouds (GRaWAC). GRaWAC is a novel Doppler-capable, FMCW G-band radar with simultaneous dual-frequency operation at 167 and 175GHz.Our recent measurement set includes observations from AWIPEV station, Ny-Alesund, the central Arctic aboard a RV Polarstern cruise, and an airborne field study with flights along the Norwegian coast and the Gulf of Bothnia.
We apply the DAR technique to our measurements to derive temporally continuous in-cloud profiles in cloudy and precipitating conditions. When deployed from aircraft, we additionally retrieve the column amount from the ground return in clear-air conditions. Advantages and limitations of water vapor profiles derived from the stand-alone DAR technique are investigated including cloud properties, retrieval resolution, and accuracy. By embedding GRaWAC measurements in a multi-frequency cloud radar synergy, we find fingerprints of precipitation-forming processes, and highlight the potential of our measurements for future model evaluation studies
Leipziger Meteorologisches Kolloquium
Das Leipziger Meteorologische Kolloquium ist eine Veranstaltungsreihe des Instituts für Meteorologie in Kooperation mit dem Institut für Troposphärenforschung e.V. und der Deutschen Meteorologischen Gesellschaft e.V.