Boundary-Layer Meteorology

, Volume 154, Issue 1, pp 57–80 | Cite as

Interactions Between Downslope Flows and a Developing Cold-Air Pool

Article

Abstract

A numerical model has been used to characterize the development of a region of enhanced cooling in an alpine valley with a width of order \(10\) km, under decoupled stable conditions. The region of enhanced cooling develops largely as a region of relatively dry air which partitions the valley atmosphere dynamics into two volumes, with airflow partially trapped within the valley by a developing elevated inversion. Complex interactions between the region of enhanced cooling and the downslope flows are quantified. The cooling within the region of enhanced cooling and the elevated inversion is almost equally partitioned between radiative and dynamic effects. By the end of the simulation, the different valley atmospheric regions approach a state of thermal equilibrium with one another, though this cannot be said of the valley atmosphere and its external environment.

Keywords

Cold-air pools Downslope flows Numerical simulation 

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Copyright information

© Springer Science+Business Media Dordrecht 2014

Authors and Affiliations

  1. 1.Centre for Atmospheric & Instrumentation Research (CAIR)University of HertfordshireHatfieldUK
  2. 2.National Centre for Atmospheric Science (NCAS), Centre for Atmospheric & Instrumentation Research (CAIR)University of HertfordshireHatfieldUK

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