Wind Shear and Turbulence on Titan: Huygens Analysis

Ralph Lorenz
(Submitted on 17 Apr 2017)

Wind shear measured by Doppler tracking of the Huygens probe is evaluated, and found to be within the range anticipated by pre-flight assessments (namely less than two times the Brunt-Vaisala frequency). The strongest large-scale shear encountered was ~5 m/s/km, a level associated with ‘Light’ turbulence in terrestrial aviation. Near-surface winds (below 4km) have small-scale fluctuations of ~0.2 m/s , indicated both by probe tilt and Doppler tracking, and the characteristics of the fluctuation, of interest for future missions to Titan, can be reproduced with a simple autoregressive (AR(1)) model. The turbulent dissipation rate at an altitude of ~500m is found to be 16 cm2/sec3, which may be a useful benchmark for atmospheric circulation models.
Comments:    19 Pages, 7 figures. Submitted to Icarus
Subjects:    Earth and Planetary Astrophysics (astro-ph.EP)
Cite as:    arXiv:1704.05113 [astro-ph.EP] (or arXiv:1704.05113v1 [astro-ph.EP] for this version)
Submission history
From: Ralph Lorenz 
[v1] Mon, 17 Apr 2017 20:10:26 GMT (187kb)
https://arxiv.org/abs/1704.05113