2017/02/26 by Tomos W. David, Laure Zanna, David, Tomos W. +3
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Atmospheric and Oceanic Physics (physics.ao-ph) #FOS: Physical sciences #Fluid Dynamics (physics.flu-dyn) #Statistical Mechanics (cond-mat.stat-mech) #Statistical Mechanics and Entropy #stochastic dynamics and bifurcation
paper · pdf · doi:10.48550/arxiv.1702.08041
openalex publication_date 2017/02/26 · openalex created_date 2022/10/01 · openalex updated_date 2026/07/28
Understanding the statistics of ocean geostrophic turbulence is of utmost\nimportance in understanding its interactions with the global ocean circulation\nand the climate system as a whole. Here, a study of eddy-mixing entropy in a\nforced-dissipative barotropic ocean model is presented. Entropy is a concept of\nfundamental importance in statistical physics and information theory; motivated\nby equilibrium statistical mechanics theories of ideal geophysical fluids, we\nconsider the effect of forcing and dissipation on eddy-mixing entropy, both\nanalytically and numerically. By diagnosing the time evolution of eddy-mixing\nentropy it is shown that the entropy provides a descriptive tool for\nunderstanding three stages of the turbulence life cycle: growth of instability,\nformation of large scale structures and steady state fluctuations. Further, by\ndetermining the relationship between the time evolution of entropy and the\nmaximum entropy principle, evidence is found for the action of this principle\nin a forced-dissipative flow. The maximum entropy potential vorticity\nstatistics are calculated for the flow and are compared with numerical\nsimulations. Deficiencies of the maximum entropy statistics are discussed in\nthe context of the mean-field approximation for energy. This study highlights\nthe importance entropy and statistical mechanics in the study of geostrophic\nturbulence.\n