Heuristic Estimation of Dust Devil Vortex Parameters and Trajectories from Single-Station Meteorological Observations : Application to InSight at Mars.

A physically-realistic migrating vortex model is developed and applied to generate pressure and wind speed and direction histories for dust devil passage. The asymmetric character of wind histories is noted, and we examine how these combined data constrain the solution space of dust devil parameters (migration velocity, diameter and intensity), ambient wind, and miss distance. These histories are compared with a new terrestrial field dataset of high-time resolution pressure and wind measurements of over twenty dust devil encounters in New Mexico . This new dataset is made available electronically and it is found that model fits can be typically achieved with simultaneous root-mean-square errors of 0.05 hPa (5-10% of the peak pressure signature), ~20 of wind azimuth, and ~2 m/s windspeed. The fits are not unique, however, and some heuristic aspects of resolving the intrinsic degeneracies of the problem and nonideal features of real encounters are discussed. The application of this approach to the InSight lander is noted, offering the possibility of defining the context for any possible detections of electromagnetic and seismic signatures of dust devils on Mars.