Atmospheric Climate Information for Urban Planning: Beijing Municipal Climate Center

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1 Atmospheric Climate Information for Urban Planning: Beijing Municipal Climate Center LINWEI LIU, WENLI GUO, XIAOYI FANG BEIJING MUNICIPAL CLIMATE CENTER (BMCC) Asia l Urban Issues INTRODUCTION The Atmospheric Environmental Impact Assessment System for Urban Planning, developed by the Beijing Municipal Climate Center in 2003, uses geographic, meteorological, and air quality data to evaluate urban layout schemes and to support urban management on different scales ranging from large cities to small communities and even individual buildings. To begin with, client organizations mainly architectural/urban planning firms and city-level government bureaus present the Climate Center with urban planning proposals that engage with factors such as development needs, property availability, economic profitability, and transportation needs. The Assessment System is then used to identify plans with the least impact on air quality and local climate. Specifically, the Beijing Municipal Climate Center uses the Assessment System to evaluate the various planning schemes and determine their effect on local atmospheric circulation and pollution diffusion. The system can be also be used to simulate emergency noxious gas accidents (e.g. to predict the diffusion path and the concentration of atmospheric pollutants) and indoor air ventilation. Though the tool was developed in Beijing city, it currently supports the urban planning operations of city government and private design firms in more than 40 cities throughout China. SOCIOECONOMIC BACKGROUND Air pollution is linked to a variety of health concerns such as respiratory disease and even cancer. While an increase in urban construction can boost economic growth, it simultaneously deteriorates air quality and, in doing so, impacts local communities. In this context, the issue of urban atmospheric management has therefore become a major concern for the city government and the general public. Private firms design urban planning proposals and use the Assessment System for pre-design insight and post-design evaluation. They then submit site proposals to the city-level planning bureau, which sends selected proposals to the Beijing Municipal Climate Center for evaluation. Ultimately, the bureaus use the Assessment System indices to identify the plan with the least environmental impact. The city planning bureaus also use the Assessment System to manage urban and rural planning and construction and to oversee construction permitting and design quality control. Clients approach the Beijing Municipal Climate Center for advice and the Center in turn develops a project to support their efforts. An indicative list of projects is included below: 1. The city cluster development in Zhujiang Delta area: At the request of the Ministry of Construction and the Guangdong Province Government, BMCC used the system to assess the general plan using quantitative indices such as UHI intensity, small wind speed (< 1m/s) distribution, inversion layer, and atmospheric self-cleaning capacity. 2. Olympic venues: In 2002, BMCC assessed the Olympic Park and the Wukesong Cultural & Sport Center planning schemes to provide basis for Beijing Municipal Commission of Urban Planning (BMCUP) to choose a most environmental friendly plan. Figure 1 shows some of the index model comparison results. The Atmospheric Environmental Impact Assessment System for Urban Planning allows the Beijing Municipal Climate Center to identify a range of options to improve urban air quality while still encouraging industrial growth. How do meteorological conditions affect the distribution of pollutants? How does the site selection of polluting industries play a role in affecting air quality? This Assessment System was developed to respond to these questions and provide support for decision-making processes. TARGET AUDIENCE The Assessment System provides information to two different primary user types: private firms that specialize in urban planning and design, and city-level government planning bureaus, which are generally responsible for urban planning activities. In both cases, users employ the Beijing Municipal Climate Center s information to identify the planning proposal with the least associated environmental risk: Figure 1. Index comparison for Olympic venues project (Source: BMCC) 1

2 3. Hangzhou Residential Community: BMCC did an assessment for two types of building layout plans for a Hangzhou residential community. For both the enclosure type and the parallel type schemes, the system analyzed the how the layout plan would affect local atmospheric environment in terms of temperature, wind pattern, and pollution dilution. CLIMATE AND CONTEXTUAL INFORMATION The concentration of pollutants in the atmosphere is dependent on several meteorological factors including wind patterns and temperature: Wind Patterns: If pollutants are discharged into the atmosphere, they disperse and their concentration decreases. When wind speeds are high, atmospheric turbulence is stronger and the pollutant thus disperses more quickly. However, when the wind speed is low, and especially when a temperature inversion layer occurs, the concentration of the pollutant increases dramatically. In urban areas such as those evaluated by the Assessment System, high-rise buildings cause micro-scale vortexes to form, which inhibits airflow and reduces wind speed. These local vortexes thereby prevent the diffusion of pollutants. Temperature: Urban heat circulation is caused by the temperature difference between urban and rural areas. In urban areas, temperature is higher than it is in rural regions and air pressure is lower. Local wind therefore blows from rural areas into the city. This phenomenon, known as the urban heat island effect, is important when considering the environmental risk associated with an urban planning proposal, particularly when the proposal involves site selection for a polluting industry. As is indicated in Figure 3, the Atmospheric Environmental Impact Assessment System for Urban Planning service includes three steps: data collection (blue), model design (green), and quantitative assessment (purple). Figure 2. Index comparison between two plans for Hangzhou Residential Community (Source: BMCC) Figure 3. Evaluation flow chart (Fang, et al., 2004) 2

3 The model design incorporates three spatial scales (Figure 4): 1) the Urban Scale Model, which includes the Regional Boundary Layer Model (RBLM) and Urban Boundary Layer Model (UBLM); 2) the Urban Sub-domain Scale Model (USSM); 3) the Building Scale Model/ Urban Street Canyon Model (USCM). The structure of the multi-scale evaluation system is shown in Figure 5. BMCC considers the meteorological conditions and pollution concentration, and provides detailed indexes such as UHI, mixing height, self-cleaning time, and so on. Finally, for each scale, an integrated index (I) weighted by detailed indexes can be obtained (Saaty, 1980). The greater the index, the better the planning scheme. Figure 4. Multi-scale modeling system (Fang, et al., 2004) Figure 5. Diagram scheme of quantitative evaluation index system (Fang, et al., 2004) 3

4 By combining the statistical analysis and model-simulated results, BMCC computes the evaluation indexes and helps decision makers evaluate different planning schemes and identify an environmentally optimal plan. In the urban planning sector, comparisons among contending designs tend to be qualitative. The quantitative index on the atmospheric environment provided by Beijing Municipal Climate Center, however, is a unique tool that can be used to identify the least impactful plan. In most cases, geographic information (terrain height, land type) and urban characteristics (building effects, surface properties and anthropogenic heating information) are obtained through a site survey conducted by the client and the Beijing Municipal Climate Center. Meanwhile, climatological data (wind, temperature, and relative humidity) is obtained from the local meteorological office. Pollution data (mainly industrial and traffic pollution) is obtained from the regional environmental protection administration. The client assumes the costs associated with data collection. Although the urban planning officials consider socioeconomic factors, such as population density, these factors are not included in the Beijing Municipal Climate Center model. Socioeconomic and climate data do not currently exist in the same format and resolution, though the former can be taken into consideration with the model results. The assessment models, specifically the initial model and boundary conditions, are customized on a per-project basis. The final assessment results as well as the index figures are delivered to the clients in the form of PowerPoint presentations and reports. Considering the interdisciplinary nature of the issue, professionals from Beijing Municipal Climate Center are sent out to explain the assessment results and the index figures throughout the process. City planning bureaus invite different design firms to submit site proposals and send selected proposals to the Beijing Municipal Climate Center for evaluation. Ultimately, the bureaus use the Assessment System indices to identify the least environmentally impactful plan. Prior to developing an urban design scheme, private firms consult the Beijing Municipal Climate Center, which uses the Assessment System to advise firms on locations in which for polluting industries are likely to have the least environmental impact. Once the firm develops several options for the city plan, the Assessment System model can be used to analyze the atmospheric impact of each plan and provide further suggestions regarding city layout and industry zone scales. The system provides decision makers with the information necessary to evaluate the pollution indexes of each planning scheme and choose the one with the least environmental impact. In 1999, the Beijing Meteorological Bureau (BMB), the Beijing Municipal Commission of Urban Planning (BMCUP), and the Beijing Environmental Protection Bureau (BEPB) put into motion the project Research on the Relationship between Urban Planning, Meteorological Conditions, and Atmospheric Pollution in Beijing. After three years of development, a multi-scale modeling system and a quantitative evaluation index system were established. The Beijing Municipal Climate Center (BMCC) began the Atmospheric Environmental Impact Assessment System for Urban Planning initiative in Initially, the Beijing Municipal Climate Center worked mostly with government organizations such as BMCUP to implement the tool. When new urban planning projects came up elsewhere throughout China, however, cities would oftentimes cooperate: The governmental network of city planning bureaus helped to introduce the service to new clients and facilitate service dissemination. Today, users include city planning bureaus, the National Ministry of Construction, and private urban planning and design firms from throughout all of China. The 2008 Summer Olympics provided a particularly important opportunity to implement the Atmospheric Environmental Impact Assessment System for Urban Planning. In July 2001, Beijing successfully won the Olympic bid. However, air pollution had always been a major challenge for the city. To ensure a healthy atmosphere for athletes and spectators, a great deal of energy was devoted to the development and implementation of air pollution control and management strategies, which ensured that the air quality goals for 2008 were met in Beijing. STAKEHOLDER INVOLVEMENT Information is collected by the Beijing Municipal Climate Center from regional metrological administrations and environmental protection bureaus. The Climate Center then uses the information in its Assessment System and produces indices that inform decision making among city-level government planning bureaus and private firms specialized in urban planning and design. Figure 6 explains a simplified version of information and service flow between each stakeholder. IMPLEMENTATION PROCESSES AND MECHANISMS STAKEHOLDER AND ISSUE IDENTIFICATION Most researchers involved with the Assessment System initiative are from the Atmospheric Environmental Assessment and Consultation Service Center of Urban Planning of the Beijing Municipal Climate Center. Data providers include regional metrological administrations and environmental protection bureaus. Figure 6. Information chain for the Atmospheric Environmental Impact Assessment System for Urban Planning 4

5 Model results and index comparisons are delivered to clients in the form of PowerPoint presentations and reports. The Assessment System often appears in urban planning and construction periodicals, which serve as another mechanism to advertise the service. FUNDING MECHANISMS This service is client-oriented and, using different inputs and boundary conditions, the assessment model is specifically customized for individual client cases. The client therefore pays for the service and in turn funds its operational costs. Since 2010, the Beijing Municipal Climate Center has been involved in an increasing number of urban development projects. In addition to city planning projects all over China, the Climate Center also contributed to the construction of the Beijing Olympic Water Park and the Beijing Financial Street reform project. MANAGEMENT AND DECISION MAKING This urban planning project was developed and implemented in its entirety by the Beijing Municipal Climate Center. Approximately 10 professionals from the Atmospheric Environmental Assessment and Consultation Service Center of Urban Planning are directly involved in the Assessment System. The client institution and the Beijing Municipal Climate Center collect the geographic data on site. Climatological data and pollution data are initially collected by the local meteorological offices and environmental protection bureaus, and are then disseminated to the Beijing Municipal Climate Center free of charge. EVALUATION The services provided to city governments are mostly long-term, and it is therefore too soon to evaluate the impact and utility of the service. However, the Beijing Municipal Climate Center s Assessment System was the first winner of the Beijing Science & Technology Award in Currently, city planning bureaus themselves, including the Beijing Municipal Commission of Urban Planning, are developing an evaluation system for urban planning, though the systems have yet to be utilized. CAPACITIES EXISTING CAPACITIES TThe Atmospheric Environmental Assessment and Consultation Service Center of Urban Planning was founded by the Beijing Municipal Climate Center to provided consulting services to urban planning, architecture design, and real estate development. With advanced IT equipment and leading researchers, the center s research focus is mainly the improvement of assessment methodology. This interdisciplinary service was developed under government policy support to improve air quality in Beijing. The vast government network of city planning bureaus and the National Ministry of Construction makes the nation-wide expansion of this service possible. therefore dependent upon the BMCC to explain the Assessment System results. Professionals from the Climate Center are sent to explain technical details and help clients to evaluate the impacts of different urban planning schemes on local air quality. CAPACITY GAPS Interdisciplinary work between the scientific and urban planning sectors is an ongoing challenge in the development of this project. Researchers at the BMCC generally do not have a thorough understanding of the issues surrounding city planning. Meanwhile, city planning personnel do not understand the technical terms and figures associated with atmospheric science. In order to solve this problem, researchers from the Climate Center are available to provide technical support in answering relevant questions and customizing models throughout the entire project design process. In doing so, the climate scientists also gain a better understanding of urban planning issues and can thus prepare for future projects. LOOKING TOWARD THE FUTURE GOALS Presently, the Assessment System project is shifting to focus on risk analysis and management. Existing assessment indices only include environmental factors, pollution factors, and the human comfort level. In the future, additional variables such as natural disaster risk will likely be incorporated into the model. The model will also be utilized in architectural design to address issues such as the shape and size of a building and the associated wind/snow resistance capacity. In the coming years, BMCC will continue to improve the modeling system and evaluation methods. Recently, a project named Research on the technology of atmospheric environment for sustainable urban planning has been proposed, in which an operational platform for evaluating the urban planning and atmospheric environment on a daily basis will be established. BMCC will also try to find additional points of overlap between climate and other science, expanding the interdisciplinary scope of the service. LESSONS LEARNED The BCCC assessment and consulting service combines atmospheric science with engineering design, and the service has proved to be effective and innovative in practical use. Moving forward with for similar interdisciplinary projects, joint efforts, close communication, and cooperation between specialists in different fields will be important in meeting the goals of both climate experts and urban planners. For most developing countries, especially those going through an economic structural change, extra emphasis on the industrial sector will invariably put pressure on the natural environment. Particularly in cases where it is impossible to eliminate the industrial polluters all together, this assessment model can be used to choose the most environmental friendly plan that safeguards human health without sacrificing economic benefits. User organizations typically do not have the expertise necessary to evaluate climate information without external support. They are 5

6 PRINCIPLES OF THE GFCS The Atmospheric Environmental Impact Assessment System for Urban Planning project incorporates Principles 1, 5, 8 of the GFCS. Principle 1: All countries will benefit, but priority shall go to building the capacity of climate-vulnerable developing countries. The assessment system can be used in cities all over the world, particularly in countries with large-scale industrial development. Principle 2: The primary goal of the Framework will be to ensure greater availability of, access to, and use of climate services for all countries. Principle 3: Framework activities will address three geographic domains; global, regional and national Principle 4: Operational climate services will be the core element of the Framework. Principle 5: Climate information is primarily an international public good provided by governments, which will have a central role in its management through the Framework. The Atmospheric Environmental Impact Assessment System for Urban Planning provides foundational information for government decision makers in urban management. Principle 6: The Framework will promote the free and open exchange of climate-relevant observational data while respecting national and international data policies. Principle 7: The role of the Framework will be to facilitate and strengthen, not to duplicate. Principle 8: The Framework will be built through user provider partnerships that include all stakeholders. This urban planning consultant service is achieved through the partnership between the user and provider. 6

7 REFERENCES Fang X. Y., Jiang W. M., Miao S. G., Zhang N., Xu M., Ji C. P., Chen X. Y., Wei J. M., 2004: The multi-scale numerical modeling system for research on the relationship between urban planning and meteorological environment. Advances in Atmospheric Sciences, 21(1), Saaty T.L., 1980:The Analytic Hierarchy Process. McGraw Hill, Inc., The Research Group of Urban Planning and Meteorological Conditions and Atmospheric Pollution in Beijing (UPMCAP), 2004: Urban Planning and Atmospheric Environment. China Meteorological Press, Beijing, pp. (in Chinese) CONTACTS Beijing Municipal Climate Center (BMCC) Address: 40 Zizhuyuan Street, Haidian District, Beijing, China Tel: (010)