Project Details
Understanding clouds and precipitation at the sub kilometer scale using HALO and ICON – Air mass transformations in the Arctic (UCP-Arctic)
Applicants
Professor Dr. Felix Ament; Dr. Vera Schemann
Subject Area
Atmospheric Science
Term
from 2020 to 2024
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 442666877
The evolution of arctic air masses is known to be important for the formation and persistence of clouds and precipitation. Two phenomena -- the warm moist intrusions from the south into the Arctic and the cold dry air outbreaks from the north -- are causing especially strong and fast changes in the air masses. During these events, the states of e.g., cloudiness, stability, and moisture budget change in space and time. Due to these fast changes and the arctic conditions with very low and often strong inversions, global models with a rather coarse resolution have difficulties to represent these processes. To create a better understanding and with that a better representation of the key processes, a combination of the detailed observations from the HALO aircraft and high-resolution simulations with the ICON-LEM will be applied within this project. Due to the long range of the HALO aircraft, it will be possible to measure the same event several times and thus gain a broad insight into the structure of the air mass. A Lagrangian flight strategy will be pursued to capture the temporal evolution of specific air masses during interesting events. The flights will be complemented by ICON-LEM simulations with locally refined resolutions along the flight path (between 1 km and 100 m). This unique combination of airborne observations and high resolution modelling will be used to estimate the moisture budget during the observed moist intrusions and cold air outbreaks. The moisture budget product will then be used to investigate the open questions like the precipitation efficiency during these changes and its influence on the persistence of arctic mixed-phase clouds. While the Lagrangian flight strategy will support the scientific questions and allow new and unique research, it causes huge challenges for the flight planning, as the movement of the air masses have to be estimated and tracked beforehand. This project will therefore also support the flight planning by performing high-resolution forecast and use these for the tracking of specific air masses. The application of an ensemble of trajectories will also help to estimate the remaining uncertainties to provide a reasonable estimate for useful flight patterns. Combining airborne observations and high resolution modelling will lead to a better understanding of the changes of the moisture budget and the persistence of mixed-phase clouds during the moist intrusions and cold air outbreaks.
DFG Programme
Infrastructure Priority Programmes