Controls on boundary layer ventilation: Boundary layer processes and large-scale dynamics

8Citations
Citations of this article
36Readers
Mendeley users who have this article in their library.

This article is free to access.

Abstract

Midlatitude cyclones are important contributors to boundary layer ventilation. However, it is uncertain how efficient such systems are at transporting pollutants out of the boundary layer, and variations between cyclones are unexplained. In this study 15 idealized baroclinic life cycles, with a passive tracer included, are simulated to identify the relative importance of two transport processes: horizontal divergence and convergence within the boundary layer and large-scale advection by the warm conveyor belt. Results show that the amount of ventilation is insensitive to surface drag over a realistic range of values. This indicates that although boundary layer processes are necessary for ventilation they do not control the magnitude of ventilation. A diagnostic for the mass flux out of the boundary layer has been developed to identify the synoptic-scale variables controlling the strength of ascent in the warm conveyor belt. A very high level of correlation (R 2 values exceeding 0.98) is found between the diagnostic and the actual mass flux computed from the simulations. This demonstrates that the large-scale dynamics control the amount of ventilation, and the efficiency of midlatitude cyclones to ventilate the boundary layer can be estimated using the new mass flux diagnostic. We conclude that meteorological analyses, such as ERA-40, are sufficient to quantify boundary layer ventilation by the large-scale dynamics. Copyright 2010 by the American Geophysical Union.

Cite

CITATION STYLE

APA

Sinclair, V. A., Gray, S. L., & Belcher, S. E. (2010). Controls on boundary layer ventilation: Boundary layer processes and large-scale dynamics. Journal of Geophysical Research Atmospheres, 115(11). https://doi.org/10.1029/2009JD012169

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free