A modeling analysis of urban canopy parameterization representing the vegetation effects in the megacity of São Paulo

Morais, Marcos Vinicius Bueno de; Freitas, Edmílson Dias de; Guerrero, Viviana Vanesa Urbina; Martins, Leila Droprinchinski

doi:10.1016/j.uclim.2016.04.004

Cited by 22 publications

(19 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The use of "urban-types" criterion instead of the local climate zones (LCZs, [32]) is due to the fact that the first is used for setting up the model urban surface configuration. This configuration has been used in several investigations in MASP by other researchers [6,31,33,34]. Thus, for the sake of consistency and comparability with previous works, we kept the urban classification system as it was originally programmed in the model, although the parameter values can be changed.…”

Section: Sky-view Factormentioning

confidence: 99%

See 1 more Smart Citation

Implementation of Observed Sky-View Factor in a Mesoscale Model for Sensitivity Studies of the Urban Meteorology

et al. 2018

View full text Add to dashboard Cite

Abstract:The sky view factor (SVF) is an important radiometric parameter for assessing the canopy energy budget of urban areas. There are several methods to determine the SVF observationally. The most common is taking a photo with a digital camera equipped with a fish-eye lens and then converting ratio of sky area to canopy area into SVF. However, most urban canopy models use this variable as derived from idealized canopy geometry. To evaluate the effect of inputting observed SVFs in numerical models, we evaluated a mesoscale model's performance in reproducing surface wind and surface temperature when subjected to different ways of SVF prescription. The studied area was the Metropolitan Area of São Paulo (MASP) in Brazil. Observed SVFs were obtained for 37 sites scattered all over the MASP. Three simulations, A, B, and C, with different SVF and aspect-ratio prescriptions, were performed to analyze the effect of SVF on the urban canopy parameterization: Simulation A (standard) used the original formulation of the Town Energy Budget (TEB) model, computing the SVFs from the aspect-ratios; Simulation B used the observed SVFs, but keeps aspect-ratios as original; and Simulation C used the aspect-ratios computed from observed SVFs. The results show that in general inputting observed SVFs improves the model capability of reproducing temperature at surface level. The comparison of model outputs with data of regular meteorological stations shows that the inclusion of observed values of SVFs enhances model performance, reducing the RMSE index by up to 3 • C. In this case, the model is able to better reproduce the expected effects in the wind field, and consequently the temperature advection, of the urban boundary layer to a large urban area. The result of Simulation C shows that the surface wind and temperature intensity for all urban types is higher than those of Simulation A, because of the lower values of the aspect ratio. The urban type with high density of tall buildings increase up to 1 m s −1 in the wind speed, and approximately 1 • C in temperature, showing the importance of a better representation of the urban structure and the SVF database improvement.

show abstract

Section: Sky-view Factormentioning

confidence: 99%

“…To consider the effect of vegetation in urban areas, a weighting average of turbulent fluxes is performed [33]:…”

Section: Modeling Systemmentioning

confidence: 99%

Implementation of Observed Sky-View Factor in a Mesoscale Model for Sensitivity Studies of the Urban Meteorology

et al. 2018

View full text Add to dashboard Cite

show abstract

“…The magnitude of Tibld is calculated using a standard resistance equal to 0.123 K•m•W −1 [61], based on building insulation values [63]. The TEB version used in this study also includes the effect of urban vegetation areas, by weighting the turbulent fluxes, as described in Morais et al [26]. The model can make use of multiple grid nesting schemes, that allows the solution of different meteorological phenomenon scales, since local to synoptic.…”

Section: Numerical Modeling Descriptionmentioning

confidence: 99%

“…The simulations were executed considering a Control Simulation, which corresponds to the closest to the real, as validated in Morais et al [26]. The model characteristics and physical parameterization are presented in Table 1, and for TEB, the main parameters are presented in Table 2.…”

Section: Simulations Descriptionsmentioning

confidence: 99%

“…However, in the daytime period, the inverse phenomenon can occur, with negative intensities of the UHI [24,25]. This effect, named Urban Cool Island, may be related to the type of material used in the constructions [26][27][28], the amount of vegetation [29,30], and the number of water bodies present in the city [31]. For Melbourne (Australia), the UHI intensity varies from −3.16 • C-6 • C [32].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sensitivity of Radiative and Thermal Properties of Building Material in the Urban Atmosphere

et al. 2019

Self Cite

View full text Add to dashboard Cite

In the context of the impact of urbanization on climate change, this work aims to evaluate the sensitivity of the thermal and radiative properties of building surfaces in urban areas to the urban heat island intensity, a local scale meteorological phenomenon. For this, variations of albedo values, emissivity, thermal conductivity and heat capacity of roofs, streets and walls were simulated through an urban scheme coupled with the BRAMS mesoscale atmospheric model for the metropolitan area of São Paulo, considering two main urban types. The simulations show that, in general, looking for cold surface situations, the change of building material can contribute to a reduction of up to 3 °C for São Paulo. In addition, the role of orientation and the typological characteristics of constructions should be taken into account. In this sense, it is expected that this work guides civil engineers and builders to search for new materials in order to reduce the effects of urbanization on the local climate.

show abstract

Impact of land use land cover on variation of urban heat island characteristics and surface energy fluxes using WRF and urban canopy model over metropolitan cities of India

Sultana

Satyanarayana

2023

Theor Appl Climatol

View full text Add to dashboard Cite

The present study focuses on the assessment of urban heat island (UHI) and urban energy uxes over Indianmetropolitan cities. For this purpose, a high resolution numerical Weather Research and Forecasting model (WRF) andacoupled single layer urban canopy model (WRF-UCM) has been implemented over Delhi, Kolkata and Hyderabad to evaluate the performance of these models in capturing the impact of urban areas in simulating the UHI over different land use land cover (LULC). The model initial conditions are obtained from NCEP-FNL reanalysis data.The model simulations reveal that the air temperature at 2 m height (T 2 ) and UHIintensityareoverestimated by WRF whereas theWRF-UCM simulationsare matching well with ERA5-Land reanalysis data considered as observations. For the WRF-UCM simulation, thestatistical errorsin T 2 and UHI intensity are within the desirable limits and the index of agreement (IoA) is more than 0.8 over the built-up areas (BA).By comparing with the satellite observations the relative surface UHI is noticed to better captured over the BA by WRF-UCM simulation. The sensible heat uxsimulated by WRF is highly overestimated whereas WRF-UCM is in good agreementwith the satellite observation over the BA. Interestingly, the latent heat ux is reasonably well simulatedover all the LULC classes.The results derived from the present study have shown the performance of WRF-UCM in simulating the spatial variation of UHI and uxes of sensible and latent heat related varied LULC classi cations over metropolitan cities of India.the USGS Earth Resources Observation Systems (EROS) data Centre for freely providing Landsat imageries used in the study. Authors are also thankful to the Weather Underground for freely availing atmospheric soundings.

show abstract

A modeling analysis of urban canopy parameterization representing the vegetation effects in the megacity of São Paulo

Cited by 22 publications

References 33 publications

Implementation of Observed Sky-View Factor in a Mesoscale Model for Sensitivity Studies of the Urban Meteorology

Implementation of Observed Sky-View Factor in a Mesoscale Model for Sensitivity Studies of the Urban Meteorology

Sensitivity of Radiative and Thermal Properties of Building Material in the Urban Atmosphere

Impact of land use land cover on variation of urban heat island characteristics and surface energy fluxes using WRF and urban canopy model over metropolitan cities of India

Contact Info

Product

Resources

About