North Pole Drifting Ice Station NP-35: Tethered Balloon Measurements
The lowest part of the atmosphere (about 1500m) is called planetary boundary layer (PBL). In the Arctic, the boundary layer is characterized by a frequent occurrence of temperature inversions, thus being a stable layer that effectively surpresses the vertical motion of air.
The realistic representation of the planetary boundary layer is of major importance in climate models, since here the lower boundary conditions are defined for all calculations.
In our project, we intend to analyse the connection between the Arctic planetary boundary layer with mesoscale cyclones and stormtracks.
Schematic of the tethered balloon system.
During the drift of NP-35, the state and variability of the planetary boundary layer will be analysed based on aerological measurements. Standard meteorological radiosoundings will be provided by the Russian colleagues twice per day. In addition, the AWI overwinterer will perform measurements with a tethered balloon system. As the focus of our studies is the spatial and temporal characterisation of the Arctic PBL, it is planned to have up to 6 meteorological sondes along the tether and operate the system for several hours during each measurement.
The interpretation of the observations will be supported by simulations with a regional climate model. The regional climate model HIRHAM will provide mesoscale pressure, temperature, and wind fields, allowing the identification of cyclones and stormtracks. Special focus will be the connection of cyclogenesis and surface conditions (e.g. sea ice cover).
Tethersondes in preparation for launch, Spitsbergen.