Observing jet stream winds through gravity waves

Falco Bentvelsen, KNMI, RDSA

Jet stream winds play an important role in our daily weather. Accurate wind and temperature estimations in the upper troposphere can lead to better medium to long-term weather forecasts. However, continuous measurement in the upper troposphere poses challenges, resulting in relatively sparse data.

This study revisits research from the 1960s and 1970s, on the use of ground-based pressure measurements as a measure for jet stream winds. It has been established that the jet stream can generate atmospheric gravity waves that radiate to the ground. Since the previous work, a global network of microbarometers has been established for verification of the Comprehensive Nuclear-Test-Ban Treaty (CTBT). This network provides continuous pressure data that holds valuable information about the jet stream.

We present results from a microbarometer array in Southern Germany (IS26). The pressure data has been processed for frequencies within a range of 0.1 - 2 mHz, where gravity waves are detected. Signal characteristics from the array analysis, such as direction-of-arrival and incidence angle, enable a detailed monitoring of the jet stream strength and direction. The characteristics of these gravity waves are compiled, and compared to hourly ECMWF ERA5 model data and other observations.

Bio / Profiel

Falco Bentvelsen is a geophysics researcher in the department of Seismology & Acoustics. Falco is keen on using techniques from acoustics in concert with other branches of KNMI. Previously he worked at RIVM and Sweco on geodata, gaussian plume modelling and Nitrogen emissions. Before that, he worked on estimating surface deformation from satellites as an InSAR engineer.  He received his MSc. diploma from TU Delft in Geoscience & Remote Sensing, with his thesis on the topic of deep convection over the Netherlands, at KNMI.