P. (Peter) Baas: “Turbulence and Low-Level Jets in the Stable Boundary Layer”

  News
  Newsroom
  Dossiers
  Archive
  Calendar
  2012
  2011
  2010
  2009
  2008
  2007
  2006
  2005
  2004
  2003
  2002
  2001
  2000
  1999
  News
  RSS
  Calendar
  Open days
  Courses
  Congresses and symposia
  PhD-graduations and speeches

14 Oct 2009 16:00
Unit: Wageningen University
Location: Aula, building 362, Gen. Foulkesweg 1, Wageningen
Organisation: Wageningen University
Promotor: prof.dr. B. Holtslag (Meteorology and Air Quality)
Co Promotor: Dr. F.C. Bosveld (KNMI, De Bilt)

 It is common knowledge that in the evening the wind close to the ground drops. However, it is less well known that at the same time the wind at a few hundreds of meters height can strongly accelerate. In this case, the vertical wind-profile shows a distinct maximum. This phenomenon is called nocturnal low-level jet (LLJ). Knowledge of the LLJ is relevant for aviation, the generation of wind energy and the distribution of pollutants. This thesis presents a climatology of LLJ characteristics (like the frequency of occurrence and the typical height at which the phenomenon occurs) for observations from the KNMI measurement site at Cabauw.

The development of nocturnal LLJs is very sensitive to the amount of turbulent mixing. In this thesis different ways on which turbulence is represented in atmospheric models are tested. Various strategies for model evaluation are discussed. This thesis aims to contribute to the understanding of physical processes and their representation in weather and climate models.
Print this activity