The Third GABLS Intercomparison Case for Evaluation Studies of Boundary-Layer Models. Part A: Case Selection and Set-Up

Autor: Fred C. Bosveld, Albert A. M. Holtslag, Erik van Meijgaard, Evert I. F. de Bruijn, Gert-Jan Steeneveld, Peter Baas
Jazyk: angličtina
Rok vydání: 2014
Předmět:
Zdroj: Boundary-Layer Meteorology 152 (2014) 2
Boundary-Layer Meteorology, 152(2), 133-156
ISSN: 0006-8314
Popis: We describe a novel methodology on the selection and composition of a single-case observational dataset from the comprehensive measurement program at the Cabauw observatory field site located in the Netherlands. The case can be regarded as the basis of the third case study conducted within the framework of the GEWEX (Global Energy and Water Exchange) Atmospheric Boundary-Layer Study (GABLS) and is meant to be used for the evaluation of single-column models. The ideal case is supposed to cover a period of at least 24 h with clear skies, moderate near-surface winds and a stable stratification during nighttime. From the multi-year data archive with Cabauw observations data for 1–2 July 2006 were found to best match the requirements, and were consequently selected for analysis. The dates contains a 24-h period with a nearly constant geostrophic wind of $$\approx $$ 7 m $$\hbox {s}^{-1}$$ , and a considerable wind shear in the vertical. It is also characterized by a pronounced low-level jet related to an inertial oscillation that developed around sunset when the atmosphere had decoupled from the surface. Detailed initial conditions, surface conditions and dynamical forcings are derived on the basis of local observations and the outcome of a conceptual and a three-dimensional atmospheric model. It appears that a very precise prescription of the forcings is a prerequisite to enable a meaningful evaluation of models against observational data.
Databáze: OpenAIRE