Improving Stable Boundary-Layer Height Estimation Using a Stability-Dependent Critical Bulk Richardson Number

H. Richardson, S. Basu, A. A.M. Holtslag

Research output: Contribution to journalArticleScientificpeer-review

24 Citations (Scopus)

Abstract

For many decades, attempts have been made to find the universal value of the critical bulk Richardson number (RiBc; defined over the entire stable boundary layer). By analyzing an extensive large-eddy simulation database and various published wind-tunnel data, we show that RiBc is not a constant, rather it strongly depends on bulk atmospheric stability. A (qualitatively) similar dependency, based on the well-known resistance laws, was reported by Melgarejo and Deardorff (J Atmos Sci 31:1324-1333, 1974) about forty years ago. To the best of our knowledge, this result has largely been ignored. Based on data analysis, we find that the stability-dependent RiBc estimates boundary-layer height more accurately than the conventional constant RiBc approach. Furthermore, our results indicate that the common practice of setting RiBc as a constant in numerical modelling studies implicitly constrains the bulk stability of the simulated boundary layer. The proposed stability-dependent RiBc does not suffer from such an inappropriate constraint.

Original languageEnglish
Pages (from-to)93-109
Number of pages17
JournalBoundary-Layer Meteorology
Volume148
Issue number1
DOIs
Publication statusPublished - 2013
Externally publishedYes

Keywords

  • Boundary-layer height
  • Large-eddy simulation
  • Low-level jet
  • Resistance laws
  • Stable boundary layer

Fingerprint Dive into the research topics of 'Improving Stable Boundary-Layer Height Estimation Using a Stability-Dependent Critical Bulk Richardson Number'. Together they form a unique fingerprint.

Cite this