Sorry, you need to enable JavaScript to visit this website.

Numerical study of the daytime planetary boundary layer over an idealized urban area: Influence of surface properties, anthropogenic heat flux, and geostrophic wind intensity

TitoloNumerical study of the daytime planetary boundary layer over an idealized urban area: Influence of surface properties, anthropogenic heat flux, and geostrophic wind intensity
Tipo di pubblicazioneArticolo su Rivista peer-reviewed
Anno di Pubblicazione2016
AutoriFalasca, S., Catalano Franco, and Moroni M.
RivistaJournal of Applied Meteorology and Climatology
Volume55
Paginazione1021-1039
ISSN15588424
Parole chiaveAnthropogenic heat flux, Aspect ratio, Atmospheric temperature, Atmospheric thermodynamics, boundary layer, Boundary layers, Budget control, Computational fluid dynamics, Energy balance, energy budget, Energy budget/balance, geostrophic flow, Heat flux, Heat island, Kinetic energy, Kinetics, Land use, Landforms, large eddy simulation, Meteorology, numerical method, Planetary boundary layers, Surface control parameters, Thermal and mechanical properties, turbulence, Turbulent kinetic energy, urban area, Weather forecasting, Weather research and forecasting models, wind forcing
Abstract

Large-eddy simulations of an idealized diurnal urban heat island are performed using the Weather Research and Forecasting Model. The surface energy balance over an inhomogeneous terrain is solved considering the anthropogenic heat contribution and the differences of thermal and mechanical properties between urban and rural surfaces. Several cases are simulated together with a reference case, considering different values of the control parameters: Albedo, thermal inertia, roughness length, anthropogenic heat emission, and geostrophic wind intensity. Spatial distributions of second-moment statistics, including the turbulent kinetic energy (TKE) budget, are analyzed to characterize the structure of the planetary boundary layer (PBL). The effect of each control parameter value on the turbulent properties of the PBL is investigated with respect to the reference case. For all of the analyzed cases, the primary source of TKE is the buoyancy in the lower half of the PBL, the shear in the upper half, and the turbulent transport term at the top. The vertical advection of TKE is significant in the upper half of the PBL. The control parameters significantly influence the shape of the profiles of the transport and shear terms in the TKE budget. Bulk properties of the PBL via proper scaling are compared with literature data. A log-linear relationship between the aspect ratio of the heat island and the Froude number is confirmed. For the first time, the effect of relevant surface control parameters and the geostrophic wind intensity on the bulk and turbulent properties of the PBL is systematically investigated at high resolution. © 2016 American Meteorological Society.

Note

cited By 4

URLhttps://www.scopus.com/inward/record.uri?eid=2-s2.0-84982833861&doi=10.1175%2fJAMC-D-15-0135.1&partnerID=40&md5=0d7b8bda24e789bfac8d0c09c657774e
DOI10.1175/JAMC-D-15-0135.1
Citation KeyFalasca20161021