FESSTVaL is a field experiment designed with the aim to capture variability that happens on scales O(100 m) to O(10 km).

Numerical Weather Prediction models operate nowadays with a grid spacing of a few kilometers and next-generation climate models have begun to employ such resolutions. Despite this, automated surface measurement networks, that routinely monitor the state of the atmosphere, typically provide measurements only every O(25) km. This is insufficient to capture processes happening on smaller scales. FESSTVaL aims to fill this gap during a dedicated field campaign.

The goals of FESSTVaL are to:

  • measure submesoscale variability by testing new measurement devices and new measurement strategies
  • validate the representation of submesoscale variability in convection-permitting models
  • use the observations for process understanding, in particular to investigate the main controls on submesoscale variability and the main effects of submesoscale variability on atmospheric properties


The main atmospheric processes targeted by FESSTVaL are coherent structures in the planetary boundary layer, cold pools and wind gusts.


FESSTVaL takes place from May to July 2020 with a special observing period in July in Lindenberg. FESSTVaL makes use of different measurement networks designed to best capture submesoscale variabiity. Besides the comprehensive measurements taken by the German Weather Service (DWD) in Lindenberg, the deployed instruments include:

  • APOLLOs (100 pieces): developed at the University of Hamburg in particular to capture cold pools by measuring temperature and pressure
  • Weather stations (25)
  • Lidars (10)
  • Solar radiation sensors (20)
  • Soil moisture and soil temperature sensors
  • MESSYs: developed at the FU Berlin, cheap self-built weather stations distributed to citizen
  • Drones and unmanned aircrafts


More detailed information on FESSTVaL can be found here