Using crop fall patterns to provide an insight into thunderstorm downburst

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.