The Experts below are selected from a list of 13179 Experts worldwide ranked by ideXlab platform
Monica Moroni - One of the best experts on this subject based on the ideXlab platform.
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numerical study of the daytime Planetary Boundary Layer over an idealized urban area influence of surface properties anthropogenic heat flux and geostrophic wind intensity
Journal of Applied Meteorology and Climatology, 2016Co-Authors: Serena Falasca, Franco Catalano, Monica MoroniAbstract:AbstractLarge-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 t...
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numerical study of the daytime Planetary Boundary Layer over an idealized urban area influence of surface properties anthropogenic heat flux and geostrophic wind intensity
Journal of Applied Meteorology and Climatology, 2016Co-Authors: Serena Falasca, Franco Catalano, Monica MoroniAbstract:AbstractLarge-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 t...
Serena Falasca - One of the best experts on this subject based on the ideXlab platform.
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numerical study of the daytime Planetary Boundary Layer over an idealized urban area influence of surface properties anthropogenic heat flux and geostrophic wind intensity
Journal of Applied Meteorology and Climatology, 2016Co-Authors: Serena Falasca, Franco Catalano, Monica MoroniAbstract:AbstractLarge-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 t...
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numerical study of the daytime Planetary Boundary Layer over an idealized urban area influence of surface properties anthropogenic heat flux and geostrophic wind intensity
Journal of Applied Meteorology and Climatology, 2016Co-Authors: Serena Falasca, Franco Catalano, Monica MoroniAbstract:AbstractLarge-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 t...
Franco Catalano - One of the best experts on this subject based on the ideXlab platform.
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numerical study of the daytime Planetary Boundary Layer over an idealized urban area influence of surface properties anthropogenic heat flux and geostrophic wind intensity
Journal of Applied Meteorology and Climatology, 2016Co-Authors: Serena Falasca, Franco Catalano, Monica MoroniAbstract:AbstractLarge-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 t...
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numerical study of the daytime Planetary Boundary Layer over an idealized urban area influence of surface properties anthropogenic heat flux and geostrophic wind intensity
Journal of Applied Meteorology and Climatology, 2016Co-Authors: Serena Falasca, Franco Catalano, Monica MoroniAbstract:AbstractLarge-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 t...
Jonathan E Pleim - One of the best experts on this subject based on the ideXlab platform.
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evaluation of Planetary Boundary Layer scheme sensitivities for the purpose of parameter estimation
Monthly Weather Review, 2010Co-Authors: John W Nielsengammon, Fuqing Zhang, Jonathan E PleimAbstract:Abstract Meteorological model errors caused by imperfect parameterizations generally cannot be overcome simply by optimizing initial and Boundary conditions. However, advanced data assimilation methods are capable of extracting significant information about parameterization behavior from the observations, and thus can be used to estimate model parameters while they adjust the model state. Such parameters should be identifiable, meaning that they must have a detectible impact on observable aspects of the model behavior, their individual impacts should be a monotonic function of the parameter values, and the various impacts should be clearly distinguishable from each other. A sensitivity analysis is conducted for the parameters within the Asymmetrical Convective Model, version 2 (ACM2) Planetary Boundary Layer (PBL) scheme in the Weather Research and Forecasting model in order to determine the parameters most suited for estimation. A total of 10 candidate parameters are selected from what is, in general, an...
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performance assessment of new land surface and Planetary Boundary Layer physics in the wrf arw
Journal of Applied Meteorology and Climatology, 2010Co-Authors: Robert C Gilliam, Jonathan E PleimAbstract:Abstract The Pleim–Xiu land surface model, Pleim surface Layer scheme, and Asymmetric Convective Model (version 2) are now options in version 3.0 of the Weather Research and Forecasting model (WRF) Advanced Research WRF (ARW) core. These physics parameterizations were developed for the fifth-generation Pennsylvania State University–National Center for Atmospheric Research Mesoscale Model (MM5) and have been used extensively by the air quality modeling community, so there was a need based on several factors to extend these parameterizations to WRF. Simulations executed with the new WRF physics are compared with simulations produced with the MM5 and another WRF configuration with a focus on the replication of near-surface meteorological conditions and key Planetary Boundary Layer features. The new physics in WRF is recommended for retrospective simulations, in particular, those used to drive air quality simulations. In the summer, the error of all variables analyzed was slightly lower across the domain in t...
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development and testing of a surface flux and Planetary Boundary Layer model for application in mesoscale models
Journal of Applied Meteorology, 1995Co-Authors: Jonathan E PleimAbstract:Abstract Although the development of soil, vegetation, and atmosphere interaction models has been driven primarily by the need for accurate simulations of long-term energy and moisture budgets in global climate models, the importance of these processes at smaller scales for short-term numerical weather prediction and air quality studies is becoming more appreciated. Planetary Boundary Layer (PBL) development is highly dependent on the partitioning of the available net radiation into sensible and latent heat fluxes. Therefore, adequate treatmentof surface properties such as soil moisture and vegetation characteristics is essential for accurate simulation of PBL development, convective and low-level cloud processes, and the temperature and humidity of Boundary Layer air. In this paper, the development ofa simple coupled surface and PBL model, which is planned for incorporation into the Pennsylvania State University-National Center for Atmospheric Research Mesoscale Model (MM4/5), is described. The soil-vege...
Axel Von Engeln - One of the best experts on this subject based on the ideXlab platform.
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a Planetary Boundary Layer height climatology derived from ecmwf reanalysis data
Journal of Climate, 2013Co-Authors: Axel Von Engeln, Joao Paulo TeixeiraAbstract:AbstractA Planetary Boundary Layer (PBL) height climatology from ECMWF reanalysis data is generated and analyzed. Different methods are first compared to derive PBL heights from atmospheric temperature, pressure, and relative humidity (RH), which mostly make use of profile gradients, for example, in RH, refractivity, and virtual or potential temperature. Three methods based on the vertical gradient of RH, virtual temperature, and potential temperature were selected for the climatology generation. The RH-based method appears to capture the inversion that caps the convective Boundary Layer very well as a result of its temperature and humidity dependence, while the temperature-based methods appear to capture the PBL better at high latitudes. A validation of the reanalysis fields with collocated radiosonde data shows generally good agreement in terms of mean PBL height and standard deviation for the RH-based method. The generated ECMWF-based PBL height climatology shows many of the expected climatological fea...
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using champ radio occultation data to determine the top altitude of the Planetary Boundary Layer
Geophysical Research Letters, 2005Co-Authors: Jens Wickert, Axel Von Engeln, Jo Ao Teixeira, Stefan BuehlerAbstract:[1] A simple approach to derive the Planetary Boundary Layer (PBL) top altitude from CHAMP (CHAllenging Minisatellite Payload) radio occultation (RO) data is presented. Our RO processing cuts off at an altitude, typically ≤4 km, below which the GPS signals are affected by tracking errors. This lowest processed altitude (LPA) is assumed to coincide with the PBL top. We average LPAs for the years 2001 to 2004 over 5 Degree latitude longitude boxes and compare them to ECMWF analysis data. The ECMWF PBL top was calculated from the relative humidity gradient with respect to altitude. Agreement between the data sets is good in terms of mean PBL height, especially over sea. The CHAMP data shows the major features of PBL height with a realistic transition from stratocumulus regions to shallow and deep cumulus areas. CHAMP also shows a substantial amount of PBL height variability that may prove useful to study PBL dynamics.
