Using crop fall patterns to provide an insight into thunderstorm downbursts: Fid-Bau Portal

Using crop fall patterns to provide an insight into thunderstorm downbursts

Sterling, M. / Huo, S. / Baker, C.J.

Abstract This paper examines whether crop fall patterns due to thunderstorm downburst-like events can provide an insight into the flow structure of a downburst. To explore this phenomenon, a novel three-dimensional analytical model for the velocity flow field is derived and coupled with a generalised plant model which is capable of modelling crop failure. Through this approach we have established the concept of the lodging front – a dimensionless variable used to quantify the spatial extent of crop failure. Crop failure is shown to result in a diverging pattern and the angles at which the crop falls has been shown to collapse onto a single curve when suitably normalised. Comparison with full-scale data suggests that the model is capable of predicting realistic crop fall patterns and could potentially be used in the future to assess the strength of downbursts.

Highlights • Crop fall due to downbursts results in a diverging flow pattern. • Crop failure is a function of downburst wind speed and its translation speed. • The crop fall angles depend on their relative location on the lodging front. • Parameters for crop failure can be calculated via the model and full-scale data.