scholarly journals Scale interactions and anisotropy in stable boundary layers

2019 ◽  
Vol 145 (722) ◽  
pp. 1799-1813 ◽  
Author(s):  
Nikki Vercauteren ◽  
Vyacheslav Boyko ◽  
Davide Faranda ◽  
Ivana Stiperski
Keyword(s):  
Boundary Layers ◽  
Stable Boundary Layers ◽  
Stable Boundary ◽  
Scale Interactions

scholarly journals On the computation of planetary boundary-layer height using the bulk Richardson number method

2014 ◽  
Vol 7 (6) ◽  
pp. 2599-2611 ◽  
Author(s):  
Y. Zhang ◽  
Z. Gao ◽  
D. Li ◽  
Y. Li ◽  
N. Zhang ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Boundary Layers ◽  
Planetary Boundary Layer ◽  
Richardson Number ◽  
Potential Temperature ◽  
Bulk Richardson Number ◽  
Stable Boundary Layers ◽  
Stable Boundary ◽  
Field Campaigns ◽  
Weakly Stable

Abstract. Experimental data from four field campaigns are used to explore the variability of the bulk Richardson number of the entire planetary boundary layer (PBL), Ribc, which is a key parameter for calculating the PBL height (PBLH) in numerical weather and climate models with the bulk Richardson number method. First, the PBLHs of three different thermally stratified boundary layers (i.e., strongly stable boundary layers, weakly stable boundary layers, and unstable boundary layers) from the four field campaigns are determined using the turbulence method, the potential temperature gradient method, the low-level jet method, and the modified parcel method. Then for each type of boundary layer, an optimal Ribc is obtained through linear fitting and statistical error minimization methods so that the bulk Richardson method with this optimal Ribc yields similar estimates of PBLHs as the methods mentioned above. We find that the optimal Ribc increases as the PBL becomes more unstable: 0.24 for strongly stable boundary layers, 0.31 for weakly stable boundary layers, and 0.39 for unstable boundary layers. Compared with previous schemes that use a single value of Ribc in calculating the PBLH for all types of boundary layers, the new values of Ribc proposed by this study yield more accurate estimates of PBLHs.

scholarly journals Large-Eddy Simulation of Stably Stratified Atmospheric Boundary Layer Turbulence: A Scale-Dependent Dynamic Modeling Approach

2006 ◽  
Vol 63 (8) ◽  
pp. 2074-2091 ◽  
Author(s):  
Sukanta Basu ◽  
Fernando Porté-Agel
Keyword(s):  
Boundary Layers ◽  
Temperature Fields ◽  
Scale Model ◽  
Subgrid Scale ◽  
Local Scaling ◽  
Stable Boundary Layers ◽  
Stable Boundary ◽  
Boundary Layer Turbulence ◽  
Scaling Hypothesis ◽  
Large Eddy

Abstract A new tuning-free subgrid-scale model, termed locally averaged scale-dependent dynamic (LASDD) model, is developed and implemented in large-eddy simulations (LES) of stable boundary layers. The new model dynamically computes the Smagorinsky coefficient and the subgrid-scale Prandtl number based on the local dynamics of the resolved velocity and temperature fields. Overall, the agreement between the statistics of the LES-generated turbulence and some well-established empirical formulations and theoretical predictions (e.g., the local scaling hypothesis) is remarkable. Moreover, the simulated statistics obtained with the LASDD model show relatively little resolution dependence for the range of grid sizes considered here. In essence, it is shown here that the new LASDD model is a robust subgrid-scale parameterization for reliable, tuning-free simulations of stable boundary layers, even with relatively coarse resolutions.

scholarly journals Large Eddies Regulate Turbulent Flux Gradients in Coupled Stable Boundary Layers

2019 ◽  
Vol 46 (11) ◽  
pp. 6090-6100 ◽  
Author(s):  
Changxing Lan ◽  
Heping Liu ◽  
Gabriel G. Katul ◽  
Dan Li ◽  
Dennis Finn
Keyword(s):  
Boundary Layers ◽  
Turbulent Flux ◽  
Stable Boundary Layers ◽  
Stable Boundary ◽  
Large Eddies

Spatiotemporal Growing Wave Fronts in Spatially Stable Boundary Layers

2006 ◽  
Vol 96 (22) ◽  
Author(s):  
T. K. Sengupta ◽  
A. Kameswara Rao ◽  
K. Venkatasubbaiah
Keyword(s):  
Boundary Layers ◽  
Wave Fronts ◽  
Stable Boundary Layers ◽  
Stable Boundary

scholarly journals Interaction Between Waves and Turbulence Within the Nocturnal Boundary Layer

2022 ◽  
Author(s):  
Francesco Barbano ◽  
Luigi Brogno ◽  
Francesco Tampieri ◽  
Silvana Di Sabatino
Keyword(s):  
Boundary Layer ◽  
Potential Energy ◽  
Boundary Layers ◽  
Wave Motion ◽  
Energy Budgets ◽  
Surface Boundary ◽  
Stable Boundary Layers ◽  
Stable Boundary ◽  
Simple Interpretation

AbstractThe presence of waves is proven to be ubiquitous within nocturnal stable boundary layers over complex terrain, where turbulence is in a continuous, although weak, state of activity. The typical approach based on Reynolds decomposition is unable to disaggregate waves from turbulence contributions, thus hiding any information about the production/destruction of turbulence energy injected/subtracted by the wave motion. We adopt a triple-decomposition approach to disaggregate the mean, wave, and turbulence contributions within near-surface boundary-layer flows, with the aim of unveiling the role of wave motion as a source and/or sink of turbulence kinetic and potential energies in the respective explicit budgets. By exploring the balance between buoyancy (driving waves) and shear (driving turbulence), a simple interpretation paradigm is introduced to distinguish two layers, namely the near-ground and far-ground sublayer, estimating where the turbulence kinetic energy can significantly feed or be fed by the wave. To prove this paradigm, a nocturnal valley flow is used as a case study to detail the role of wave motions on the kinetic and potential energy budgets within the two sublayers. From this dataset, the explicit kinetic and potential energy budgets are calculated, relying on a variance–covariance analysis to further comprehend the balance of energy production/destruction in each sublayer. With this investigation, we propose a simple interpretation scheme to capture and interpret the extent of the complex interaction between waves and turbulence in nocturnal stable boundary layers.

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