Open AccessObservations of Transient Linear Organization and Nonlinear Scale Interactions in Lake-Effect Clouds. Part II: Nonlinear Scale Interactions
Author(s) -
N. L. Miles,
Johannes Verlinde
Publication year - 2005
Publication title -
monthly weather review
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.862
H-Index - 179
eISSN - 1520-0493
pISSN - 0027-0644
DOI - 10.1175/mwr-2880.1
Subject(s) - turbulence , nonlinear system , convection , scale (ratio) , transient (computer programming) , kinetic energy , vortex , mechanics , meteorology , turbulence kinetic energy , geology , atmospheric sciences , climatology , physics , environmental science , classical mechanics , computer science , quantum mechanics , operating system
Linearly organized convection and associated horizontal roll vortices occasionally occur in atmospheric conditions in which theory predicts only cellular organization. One possible contributor to the occurrence of rolls in such conditions is nonlinear interactions between different scales of motion. In the winter of 1997/98, the Lake-Induced Convection Experiment (Lake-ICE) was conducted in part to investigate scale interactions in linearly organized convection. As discussed in Part I of this series, transient linear organization was observed during a wintertime lake-effect event during Lake-ICE. In Part II two-part nonlinear scale interactions and their possible role in the occurrence of linear organization in an unfavorable environment are investigated. Turbulence-scale vertical velocity variance peaks were consistently observed during roll strengthening and decay, suggesting a link between the scales. Composites of the nonlinear interaction terms in the roll-scale vertical turbulent kinetic energy (TKE) budget revealed that nonlinear interactions between the roll and turbulence scales were large compared to the observed change in roll-scale TKE, but do not coincide in time.