The FESST@MOL and FESST@HH pre-campaigns for FESSTVaL were used in 2019 and 2020 to test the different measurement systems that would be used at FESSTVaL.

Data access: The datasets from the pre-campaigns are available under the link FESST@home 2020.

FESST@MOL – Pre-campaign for FESSTVaL

A central component of FESSTVaL are measurements with Doppler lidar systems to record wind and turbulence information in the atmospheric boundary layer (ABL). As part of the FESST@MOL pre-campaign, a total of eight Doppler lidar systems were deployed at the Falkenberg boundary layer measuring field from June to August 2020.

Goals of FESST@MOL:

• Comparison of Doppler lidar measurement configurations to determine wind profiles and turbulent kinetic energy (TKE) and their validation through in-situ measurements on the 99-meter mast.
• Verification of the accuracy of wind and turbulence measurements with Doppler lidar by comparing them with UAV measurements.
• Test of new measurement configurations to record and characterise wind gusts using Doppler lidar data.

• Investigation of the three-dimensional wind and turbulence structure of the ABL over a heterogeneous land surface during the course of the day.

Measurement methods & scan configurations:

To achieve these goals, the Doppler lidar systems were operated in various scanning modes, including:

• Vertical beam
• Virtual tower
• Stepwise or continuous conical scan
• Horizontal or vertical sector scan (PPI, RHI)

FESST@HH (2020, Hamburg) – Pre-campaign for FESSTVaL

As a preparatory campaign for FESSTVaL, FESST@HH was carried out in Hamburg in summer 2020. The measurements were organized by the Meteorological Institute of the University of Hamburg and the Max Planck Institute for Meteorology.

Goals of FESST@HH:

Study of cold pools – small-scale areas of cold air that form beneath raining clouds and often occur during thunderstorms. Measuring stations:

• APOLLO (Autonomous Cold Pool Logger):
  • Measured variables: temperature, air pressure
  • Recording: every second
  • Battery life: 10 to 14 days
• WXT (Weather Transmitter Vaisala WXT 536):
  • Measured variables: temperature, humidity, air pressure, wind
  • Recording: every 10 seconds
  • Battery life: infinite (solar supported)