scholarly journals Multi-site evaluation of an urban land-surface model: intra-urban heterogeneity, seasonality and parameter complexity requirements

2011 ◽  
Vol 138 (665) ◽  
pp. 1094-1113 ◽  
Author(s):  
Thomas Loridan ◽  
C.S.B. Grimmond
Keyword(s):  
Land Surface ◽  
Land Surface Model ◽  
Urban Land ◽  
Surface Model ◽  
Site Evaluation

scholarly journals A Python-enhanced urban land surface model SuPy (SUEWS in Python, v2019.2): development, deployment and demonstration

2019 ◽  
Author(s):  
Ting Sun ◽  
Sue Grimmond
Keyword(s):  
Land Surface ◽  
Urban Climate ◽  
Land Surface Model ◽  
Urban Land ◽  
Surface Model ◽  
Climate Modelling ◽  
Climate Services ◽  
Mass Fluxes ◽  
Online Tutorials ◽  
Urban Energy

Abstract. Accurate and agile modelling of the climate of cities is essential for urban climate services. The Surface Urban Energy and Water balance Scheme (SUEWS) is a state-of-the-art, widely used, urban land surface model (ULSM) which simulates urban-atmospheric interactions by quantifying the energy, water and mass fluxes. Using SUEWS as the computation kernel, SuPy (SUEWS in Python), stands on the Python-based data stack to streamline the pre-processing, computation and post-processing that are involved in the common modelling-centred urban climate studies. This paper documents the development of SuPy, which includes the SUEWS interface modification, F2PY (Fortran to Python) configuration and Python frontend implementation. In addition, the deployment of SuPy via PyPI (Python Package Index) is introduced along with the automated workflow for cross-platform compilation. This makes SuPy available for all mainstream operating systems (Windows, Linux, and macOS). Furthermore, three online tutorials in Jupyter notebooks are provided to users of different levels to become familiar with SuPy urban climate modelling. The SuPy package represents a significant enhancement that supports existing and new model applications, reproducibility, and enhanced functionality.

scholarly journals Impact of Urbanization on Heavy Convective Precipitation under Strong Large-Scale Forcing: A Case Study over the Milwaukee–Lake Michigan Region

2014 ◽  
Vol 15 (1) ◽  
pp. 261-278 ◽  
Author(s):  
Long Yang ◽  
James A. Smith ◽  
Mary Lynn Baeck ◽  
Elie Bou-Zeid ◽  
Stephen M. Jessup ◽  
...  
Keyword(s):  
Land Surface ◽  
Large Scale ◽  
Lake Michigan ◽  
Land Surface Model ◽  
Urban Land ◽  
Surface Model ◽  
Urban Representations ◽  
Simulation Results ◽  
Impact Of Urbanization ◽  
The City

Abstract In this study, observational and numerical modeling analyses based on the Weather Research and Forecasting Model (WRF) are used to investigate the impact of urbanization on heavy rainfall over the Milwaukee–Lake Michigan region. The authors examine urban modification of rainfall for a storm system with continental-scale moisture transport, strong large-scale forcing, and extreme rainfall over a large area of the upper Midwest of the United States. WRF simulations were carried out to examine the sensitivity of the rainfall distribution in and around the urban area to different urban land surface model representations and urban land-use scenarios. Simulation results suggest that urbanization plays an important role in precipitation distribution, even in settings characterized by strong large-scale forcing. For the Milwaukee–Lake Michigan region, the thermodynamic perturbations produced by urbanization on the temperature and surface pressure fields enhance the intrusion of the lake breeze and facilitate the formation of a convergence zone, which create favorable conditions for deep convection over the city. Analyses of model and observed vertical profiles of reflectivity using contoured frequency by altitude displays (CFADs) suggest that cloud dynamics over the city do not change significantly with urbanization. Simulation results also suggest that the large-scale rainfall pattern is not sensitive to different urban representations in the model. Both urban representations, the Noah land surface model with urban land categories and the single-layer urban canopy model, adequately capture the dominant features of this storm over the urban region.

scholarly journals Intercomparison between the Integrated Urban land Model and the Noah Urban Canopy Model

2020 ◽  
Author(s):  
Chunlei Meng ◽  
Junxia Dou
Keyword(s):  
Heat Flux ◽  
Solar Radiation ◽  
Human Activity ◽  
Land Surface ◽  
Land Surface Model ◽  
Urban Canopy ◽  
Urban Land ◽  
Surface Model ◽  
Urban Canopy Model ◽  
Canopy Model

Abstract. Urban land surface model (ULSM) is an important tool to study the climatic effect of human activity. Now there are two main methods to parameterize the effects of human activity, the coupling method and the integrating method. For the coupled method, the urban canopy model (UCM) was developed and coupled with the land surface model for the natural land surfaces. For the integrated method, the urban land surface model was built directly based on the traditional land surface model. In this paper, the Noah Single Layer Urban Canopy Model (Noah/SLUCM) and the Integrated Urban land Model (IUM) were compared using the observed fluxes data at the 325-meter meteorology tower in Beijing. Through the comparison, the key factors and physical processes of the urban land surface model which have significant impact on the performance of ULSM were found out. The results indicate that the absorbed solar radiation of urban surface was reduced by the solar radiation scattering, the absorption of building roof and wall, and the shading effect of urban canopy and tall buildings. Urban surface roughness length and friction velocity are important in urban sensible heat flux simulation. Urban water balance and impervious surface evaporation (ISE) are important in urban latent heat flux simulation.

scholarly journals A Python-enhanced urban land surface model SuPy (SUEWS in Python, v2019.2): development, deployment and demonstration

2019 ◽  
Vol 12 (7) ◽  
pp. 2781-2795 ◽  
Author(s):  
Ting Sun ◽  
Sue Grimmond
Keyword(s):  
Land Surface ◽  
Urban Climate ◽  
Land Surface Model ◽  
Urban Land ◽  
Surface Model ◽  
Climate Modelling ◽  
Mass Fluxes ◽  
Online Tutorials ◽  
Urban Energy ◽  
Cross Platform

Abstract. Accurate and agile modelling of cities weather, climate, hydrology and air quality is essential for integrated urban services. The Surface Urban Energy and Water balance Scheme (SUEWS) is a state-of-the-art widely used urban land surface model (ULSM) which simulates urban–atmospheric interactions by quantifying the energy, water and mass fluxes. Using SUEWS as the computation kernel, SuPy (SUEWS in Python) uses a Python-based data stack to streamline the pre-processing, computation and post-processing that are involved in the common modelling-centred urban climate studies. This paper documents the development of SuPy, including the SUEWS interface modification, F2PY (Fortran to Python) configuration and Python front-end implementation. In addition, the deployment of SuPy via PyPI (Python Package Index) is introduced along with the automated workflow for cross-platform compilation. This makes SuPy available for all mainstream operating systems (Windows, Linux and macOS). Three online tutorials in Jupyter Notebook are provided to users of different levels to become familiar with SuPy urban climate modelling. The SuPy package represents a significant enhancement that supports existing and new model applications, reproducibility and enhanced functionality.

scholarly journals Key Conclusions of the First International Urban Land Surface Model Comparison Project

2015 ◽  
Vol 96 (5) ◽  
pp. 805-819 ◽  
Author(s):  
M. J. Best ◽  
C. S. B. Grimmond
Keyword(s):  
Land Surface ◽  
Model Comparison ◽  
Land Surface Model ◽  
Urban Land ◽  
Shortwave Radiation ◽  
Width Ratio ◽  
Surface Model ◽  
Street Canyons ◽  
Plan View ◽  
Global Parameter

Abstract The First International Urban Land Surface Model Comparison was designed to identify three aspects of the urban surface–atmosphere interactions: 1) the dominant physical processes, 2) the level of complexity required to model these, and 3) the parameter requirements for such a model. Offline simulations from 32 land surface schemes, with varying complexity, contributed to the comparison. Model results were analyzed within a framework of physical classifications and over four stages. The results show that the following are important urban processes: i) multiple reflections of shortwave radiation within street canyons; ii) reduction in the amount of visible sky from within the canyon, which impacts the net longwave radiation; iii) the contrast in surface temperatures between building roofs and street canyons; and iv) evaporation from vegetation. Models that use an appropriate bulk albedo based on multiple solar reflections, represent building roof surfaces separately from street canyons and include a representation of vegetation demonstrate more skill, but require parameter information on the albedo, height of the buildings relative to the width of the streets (height to width ratio), the fraction of building roofs compared to street canyons from a plan view (plan area fraction), and the fraction of the surface that is vegetated. These results, while based on a single site and less than 18 months of data, have implications for the future design of urban land surface models, the data that need to be measured in urban observational campaigns, and what needs to be included in initiatives for regional and global parameter databases.

scholarly journals Efficiently modelling urban heat storage: an interface conduction scheme in an urban land surface model (aTEB v2.0)

2017 ◽  
Vol 10 (2) ◽  
pp. 991-1007 ◽  
Author(s):  
Mathew J. Lipson ◽  
Melissa A. Hart ◽  
Marcus Thatcher
Keyword(s):  
Heat Transfer ◽  
Exact Solutions ◽  
Land Surface ◽  
Heat Storage ◽  
Model Performance ◽  
Land Surface Model ◽  
Urban Land ◽  
Surface Model ◽  
High Level ◽  
Interface Conduction

Abstract. Intercomparison studies of models simulating the partitioning of energy over urban land surfaces have shown that the heat storage term is often poorly represented. In this study, two implicit discrete schemes representing heat conduction through urban materials are compared. We show that a well-established method of representing conduction systematically underestimates the magnitude of heat storage compared with exact solutions of one-dimensional heat transfer. We propose an alternative method of similar complexity that is better able to match exact solutions at typically employed resolutions. The proposed interface conduction scheme is implemented in an urban land surface model and its impact assessed over a 15-month observation period for a site in Melbourne, Australia, resulting in improved overall model performance for a variety of common material parameter choices and aerodynamic heat transfer parameterisations. The proposed scheme has the potential to benefit land surface models where computational constraints require a high level of discretisation in time and space, for example at neighbourhood/city scales, and where realistic material properties are preferred, for example in studies investigating impacts of urban planning changes.

scholarly journals A building energy demand and urban land surface model

2018 ◽  
Vol 144 (714) ◽  
pp. 1572-1590 ◽  
Author(s):  
Mathew J. Lipson ◽  
Marcus Thatcher ◽  
Melissa A. Hart ◽  
Andrew Pitman
Keyword(s):  
Land Surface ◽  
Energy Demand ◽  
Land Surface Model ◽  
Building Energy ◽  
Urban Land ◽  
Surface Model

Urbanisation of weather data lead for more sustainable building design: urban land surface model used to generate Typical Meteorological Year (TMY) datasets

2020 ◽  
Author(s):  
Ting Sun ◽  
Yihao Tang ◽  
Jie Xiong ◽  
Hamidreza Omidvar ◽  
Sue Grimmond
Keyword(s):  
Land Surface ◽  
Large Scale ◽  
Land Surface Model ◽  
Building Design ◽  
Building Energy ◽  
Urban Land ◽  
Reanalysis Data ◽  
Weather Data ◽  
Surface Model ◽  
The Impact

<p>Typical Meteorological Year (TMY) datasets are widely used in building energy design simulations to assess needs (cooling/heat). Currently, TMY data used are representative of the past climate (from observations) of the region and generally do not account for urban climate or building-city interactions. Here we use an urban land surface model, SUEWS (Surface Urban Energy and Water Balance Scheme) driven by ERA5 reanalysis data to bridge this gap.</p><p>Using 0.25 ° large-scale ERA5 reanalysis data (1979–2018) with SUEWS we generate an urbanised TMY (uTMY) dataset for Changsha, a city with more than 4.4 million residents in the hot-summer-cold-winter region of China, to demonstrate the proposed workflow. The SUEWS simulation are evaluated at the Leifeng site (WMO code 57687) for 2016.</p><p>Through comparison of DOE EnergyPlus simulations, we also assess the impact on design building energy consumption using uTMY and cTMY (conventional TMY) data. The building design energy needs evaluation is for a common Chinese apartment building. This should allow for more spatially explicit building design, and hence more sustainable.</p>

Sign in / Sign up

Export Citation Format

Share Document