TUKUP6: Indicators and climate maps II : urban planning
Preparing urban climate maps using Local Climate Zones (LCZ) methodology to improve communication with urban planners: the case of Tandil city, Argentina
1IGEHCS - CONICET/UNCPBA, Argentine Republic; 2Departamento de Geografía y Turismo, UNS, Argentine Republic
Local Climate Zones (LCZ) is a new methodology to improve the characterization of urban station localization. This new methodology has great potential to prepare urban climate maps and improve the way of communicating the results of urban climate research to urban planners. These kinds of maps are a highly accurate way to inform of the application of new mitigation strategies related to the climatic and construction characteristics of a city.
Tandil is a mid city located in Buenos Aires province in Argentina. It has a transition temperate climate and is surrounded by the center of Tandilia’s Hill System from west to south. It takes up the top and middle basin of river Langueyú. The city’s population is of 116,916 inhabitants and it has a diversified economy with a well developed service sector.
This is the first study in it’s kind in Argentina. The preparation of the LCZ map of Tandil takes into account such climatic information as temperature, humidity, precipitation, wind and comfort. This data was obtained throughout a three year measurements using meteorological stations and transect methods. Urban characterization parameters regarding construction, population density and land use were employed to build up the LCZ map.
As a result, 17 LCZs were determined in Tandil, each one with its own climatic and construction characterization. The analysis of each LCZ situation puts into context the need to improve the already existing urban development plan which does not take into account climatic parameters. The mitigation strategies were mainly based on three types of intervention: gas emission control, improvement of urban vegetation and some construction restrictions.
The map made it possible to improve the communication of the results to the urban planner since it contains the climatic and construction characteristics of each zone, the relation between both and the mitigation strategies that should be implemented to mitigate the negative effects that changes made by the city construction have caused in the population.
Urban Climate Zoning for Making "Hint Map for Urban Planning"
Hiroshima University, Japan
In recent year, urban heat island phenomena caused by land cover change or increase of anthropogenic heat release occurs in many cities of Japan. The temperature rises in urban area because of this urban heat island phenomenon and global climate change. Accordingly, various problems have happened, for example, the uncomfortable outdoor environment in summer, the increase of energy consumption, the effect on urban ecosystem and the damage to human health. In Hiroshima, reportedly, the severe urban heat island phenomenon engenders high temperatures. Therefore, urban planning incorporating mitigation of the urban heat island phenomenon is needed in Hiroshima. The authors intend to produce Urban Environmental Climate Maps of Hiroshima as the ultimate objective of this study.
Few examples in which planners (or stakeholders) consider urban heat island phenomenon mitigation based on scientific knowledge in their planning processes exist. That is true apparently because the urban climate phenomenon is difficult to understand for stakeholders: residents, local government officials, designers, and planners. UECMs are therefore proposed as a tool for supporting urban planning. Although trial UECMs incorporating urban heat island mitigation have been made in Japan, their definition is slightly different due to each of them. Therefore, the authors supply a definition for UECMs as follows. “UECMs are made for urban planning, architectural design, and environmental policy making that considering urban heat island mitigation. The role of this map is to provide some information from the view of urban climate to the place of decision making (including public involvement). Therefore, the purpose of creating these maps is to support design. On UECMs, the essence of climate research results and recommendations by experts are described. When stakeholders (citizen, planner, architect, specialist, and so on.) make decision about urban planning, architecture design, and environmental policy making, they and experts can use these maps as communication tools.” Actually, UECMs consists of a Climate Analysis Map (CAM) and a Hint Map for Urban Planning and Design (HM). The role of CAM is representing actual climate conditions. That of HM is representing the recommendations for urban planning and design.
In Japan, trial UECMs has been made for Tokyo and Osaka. Those maps, which show the present climate conditions of the object area (e.g. wind patterns), are thought to be effective in elucidating present climate conditions. However, when trying to produce an urban plan that incorporates urban heat island mitigation, practical countermeasures are difficult for many people to decide. UECMs should therefore include recommendations for urban planners. On the other hand, some maps presenting recommendations have been made at the district level, showing some proposals from a climatic environment perspective. However, such maps showing recommendations for entire city areas are also needed. Because stakeholders must incorporate various elements in their process when they plan the whole city area, the map should show issues to be considered in planning processes and climatic resources, rather than only actual proposals. Therefore, indicating zones that are classified from a climatic perspective is thought to be effective. This study analyzes the urban heat island phenomenon in Hiroshima using a meso-scale meteorological model and observed data, yielding a climate zoning based on the analyses, with a map providing hints for planning.
A GIS-based Modelling-Mapping Approach for Fine-Scale Natural Ventilation Evaluation in High Density Cities
1Massachusetts Institute of Technology, United States of America; 2The Chinese University of Hong Kong, Hong Kong; 3Singapore University of Technology and Design, Singapore
Analysis of urban aerodynamics properties is important on urban planning and design to improve the current living quality in high-density urban areas. These analyses, particularly at pedestrian level, depend on high resolution modeling. Aerodynamic modelling for the real urban design or planning project requires high computational cost; thus, modelling results cannot sustain quick planning and design processes. Therefore, this study aimed to develop a low-cost Geography Information System (GIS)-based modelling–mapping approach to estimate and map the pedestrian-level wind speed at high resolution for the urban planning and design practices. Based on the analysis of the momentum transfer in the street canyon, the point-based distance-weighted frontal area density (lambda f-point) was developed as a new indicator to evaluate city-scale air ventilation. Annual average wind speed data from wind tunnel experiments were entered into regression models with lambda f-point. lambda f-point was validated as a good indicator to assess the annually average wind environment, and the regression equations were correspondingly developed to estimate the pedestrian-level wind speed by pixel (1m × 1m). This GIS-based modeling–mapping approach consumes considerably less time and requires less support technology compared with CFD simulation and wind tunnel experiments. Using this practical tool with GIS data, urban planners and architects can easily estimate local near-ground wind environment and optimize proposed planning and designs at the beginning of design procedure to improve the environmental quality in urban areas.