Lagrangian mixing in an axisymmetric hurricane model 1Department of Mathematics, Colorado State University, Fort Collins, CO 80523-1874, USA
2Department of Meteorology, Naval Postgraduate School, Monterey, CA 93943-5114, USA
Received: 23 Jul 2009 – Published in Atmos. Chem. Phys. Discuss.: 09 Sep 2009 Abstract. This paper discusses the extension of established Lagrangian mixing measures
to make them applicable to data extracted from a 2-D axisymmetric hurricane
simulation. Because of the non-steady and unbounded characteristics of the
simulation, the previous measures are extended to a moving frame approach
to create time-dependent mixing rates that are dependent upon the initial
time of particle integration, and are computed for nonlocal regions. The
global measures of mixing derived from finite-time Lyapunov exponents,
relative dispersion, and a measured mixing rate are applied to distinct regions
representing different characteristic feautures within the model. It is
shown that these time-dependent mixing rates exhibit correlations with
maximal tangential winds during a quasi-steady state, establishing a
connection between mixing and hurricane intensity.
Revised: 15 Jun 2010 – Accepted: 15 Jul 2010 – Published: 23 Jul 2010
Citation: Rutherford, B., Dangelmayr, G., Persing, J., Kirby, M., and Montgomery, M. T.: Lagrangian mixing in an axisymmetric hurricane model, Atmos. Chem. Phys., 10, 6777-6791, doi:10.5194/acp-10-6777-2010, 2010.