Please use this identifier to cite or link to this item:
|Title:||Mixing layer formation near the tropopause due to gravity wave-critical level interactions in a cloud-resolving model|
|Citation:||Moustaoui, M., Joseph, B., Teitelbaum, H. (2004-12-15). Mixing layer formation near the tropopause due to gravity wave-critical level interactions in a cloud-resolving model. Journal of the Atmospheric Sciences 61 (24) : 3112-3124. ScholarBank@NUS Repository. https://doi.org/10.1175/JAS-3289.1|
|Abstract:||A plausible mechanism for the formation of mixing layers in the lower stratosphere above regions of tropical convection is demonstrated numerically using high-resolution, two-dimensional (2D), anelastic, nonlinear, cloud-resolving simulations. One noteworthy point is that the mixing layer simulated in this study is free of anvil clouds and well above the cloud anvil top located in the upper troposphere. Hence, the present mechanism is complementary to the well-known process by which overshooting cloud turrets causes mixing within stratospheric anvil clouds. The paper is organized as a case study verifying the proposed mechanism using atmospheric soundings obtained during the Central Equatorial Pacific Experiment (CEPEX), when several such mixing layers, devoid of anvil clouds, had been observed. The basic dynamical ingredient of the present mechanism is (quasi stationary) gravity wave-critical level interactions, occurring in association with a reversal of stratospheric westerlies to easterlies below the tropopause region. The robustness of the results is shown through simulations at different resolutions. The insensitivity of the qualitative results to the details of the subgrid scheme is also evinced through further simulations with and without subgrid mixing terms. From Lagrangian reconstruction of (passive) ozone fields, it is shown that the mixing layer is formed kinematically through advection by the resolved-scale (nonlinear) velocity field. © 2004 American Meteorological Society.|
|Source Title:||Journal of the Atmospheric Sciences|
|Appears in Collections:||Staff Publications|
Show full item record
Files in This Item:
There are no files associated with this item.
checked on Sep 20, 2018
WEB OF SCIENCETM
checked on Sep 10, 2018
checked on Sep 13, 2018
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.