15th European Turbulence Conference 2015
August 25-28th, 2015, Delft, The Netherlands
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Excess statistics with applications to turbulence in marine environments


Go-down etc15 Tracking Number 277

Presentation:
Session: Lagrangian aspects of turbulence 3
Room: Room F
Session start: 15:00 Thu 27 Aug 2015

Hans Pecseli   hans.pecseli@fys.uio.no
Affifliation: University of Oslo, Norway

Jan Trulsen   j.k.trulsen@astro.uio.no
Affifliation: University of Oslo, Norway


Topics: - Lagrangian aspects of turbulence

Abstract:

Studies of excess statistics are standard in signal analysis, addressing basic questions like average frequencies of level crossings in a random signal, and average time durations between an up- and a down-crossing. The results can be applied to estimating the noise experienced by aquatic microorganisms in a turbulent environment. This problem has particular interest in relations to predators and prey that rely solely on signals transmitted through the surrounding turbulent flow. It is possible to give estimates for how often a predator can mistake turbulent induced noise for a signal from prey in given turbulence conditions. Such mistakes can be observed as unmotivated attacks. Similarly, prey can mistake noise for presence of a predator, giving rise to seemingly unmotivated observable escape responses.