The Inaugural CBE Climate Solutions Symposium took place on May 23, 2024. The event began with a reception and poster session, followed by an invited lecture “Every Project is a Climate Opportunity” with Don Davies, PE, SE and Joan Crooks. 36 research posters were submitted and accepted to the symposium. The posters covered a range of topics, from affordable housing in Indonesia (Bella Septianti, Architecture/Design Technology), to CLT and structural steel comparative lifecycle assessment (Mira Malden, Community, Environment, and Planning)….
Person: Christine Bae
Carb talk: CBE’s Climate Solutions Community of Practice sparks interdisciplinary collaborations
The CBE Climate Solutions Community of Practice was featured in a story on the CBE website. See the excerpt below. “Through the materials we use and the ecosystems we alter, arguably more than 40% of global greenhouse gas emissions are related to the built environment,” says Kate Simonen, a professor of architecture at UW’s College of Built Environments and founding director of the Carbon Leadership Forum. Simonen’s primary research focus is reducing the environmental impact of building materials, and she’s been…
Assessing Multifamily Residential Parking Demand and Transit Service
Rowe, Daniel H.; Bae, Chang-hee Christine; Shen, Qing. (2010). Assessing Multifamily Residential Parking Demand and Transit Service. Ite Journal-institute Of Transportation Engineers, 80(12), 20 – 24.
Abstract
This study examined the relationship of multifamily residential parking demand and transit level of service in Two King County, WA, USA, Urban Centers: First Hill/Capitol Hill (FHCH) and redmond. In addition, current parking policies were assessed for their ability to meet the observed parking demand, and an alternative method to collect parking demand data was explored.
Evaluating the Impact of Transit Service on Parking Demand and Requirements
Rowe, Daniel H.; Bae, Christine; Shen, Qing. (2011). Evaluating the Impact of Transit Service on Parking Demand and Requirements. Transportation Research Record, 2245, 56 – 62.
Abstract
Many jurisdictions in the United States typically set minimum parking requirements for residential multifamily developments based on old data that were collected in suburban settings with little transit availability. Such parking requirements applied to urban settings with adequate transit service often result in an oversupply of parking, which in turn creates a barrier to smart growth. Not only does the oversupply of parking encourage automobile use and reduce housing affordability, but it also increases development costs, consumes land and natural resources, and increases associated air and water pollution. This research examines the relationship of parking demand and transit service in First Hill Capitol Hill (FHCH) and Redmond, two urban centers in King County, Washington. An alternative method to collect parking demand data is explored. The results show a strong relationship between transit service and parking demand. The FHCH urban center, which abuts downtown Seattle, exhibited higher levels of transit service and lower parking demand. Parking demand in FHCH was observed to be 0.52 parking space per dwelling unit, which was about 50% less than parking demand observed in Redmond, a growing mixed-use suburban center, and 50% less than data reported by the Institute of Transportation Engineers. After a review of the parking policies of each urban center, opportunities to improve regulations including adjusting minimum parking requirements and allowing for reductions in required parking when developers implement solutions to reduce demand for parking were identified.
Impact of Gasoline Prices on Transit Ridership in Washington State
Stover, Victor W.; Bae, C.-H. Christine. (2011). Impact of Gasoline Prices on Transit Ridership in Washington State. Transportation Research Record, 2217, 1 – 10.
Abstract
Gasoline prices in the United States have been extremely volatile in recent years and rose to record high levels during the summer of 2008. According to the U.S. Energy Information Administration, the average U.S. gasoline price for the year 2008 was $3.26 a gallon, which was the second highest yearly average in history when adjusted for inflation. Transportation agencies reported changes in travel behavior as a result of the price spike, with transit systems experiencing record ridership and state departments of transportation reporting reductions in traffic volumes. This study examined the impact of changing gasoline prices on transit ridership in Washington State by measuring the price elasticity of demand of ridership with respect to gasoline price. Ordinary least-squares regression was used to model transit ridership for transit agencies in 11 counties in Washington State during 2004 to 2008. The price of gasoline had a statistically significant effect on transit ridership for seven systems studied, with elasticities ranging from 0.09 to 0.47. A panel data model was estimated with data from all 11 agencies to measure the overall impact of gasoline prices on transit ridership in the state. The elasticity from the panel data model was 0.17. Results indicated that transit ridership increased as gasoline prices increased during the study period. The findings were consistent with those from previous studies on the topic.
Keywords
Time-series Analysis; Gas Prices; Elasticities; Demand
Exposure of Bicyclists to Air Pollution in Seattle, Washington Hybrid Analysis Using Personal Monitoring and Land Use Regression
Hong, E-Sok Andy; Bae, Christine. (2012). Exposure of Bicyclists to Air Pollution in Seattle, Washington Hybrid Analysis Using Personal Monitoring and Land Use Regression. Transportation Research Record, 2270, 59 – 66.
Abstract
The increase in urban bicycling facilities, raises public health concerns for potential exposure of bicyclists to traffic emissions. For an assessment of bicyclists' exposure to local traffic emissions, a hybrid approach is presented; it combines personal monitoring and a land use regression (LUR) model. Black carbon, a proxy variable for traffic-related air pollution, was measured with an Aethalometer along the predesignated bicycle route in Seattle, Washington, for 10 days, during a.m. and p.m. peak hours (20 sampling campaigns). Descriptive statistics and three-dimensional pollution maps were used to explore temporal variations and to identify pollution hot spots. The LUR model was developed to quantify the influence of spatial covariates on black carbon concentrations along the designated route. The results indicated that the black carbon concentrations fluctuated throughout the sampling periods and showed statistically significant diurnal and monthly patterns. The hot spot analysis suggests that proximity to traffic and other physical environments have important impacts on bicyclists' exposure and demand further investigation on the localized effects of traffic emissions on exposure levels. The LUR model explains 46% of the variations in black carbon concentrations, and significant relationships are found with types of bicycle route facility, wind speed, length of truck routes, and transportation and utility land uses. This research is the first application of the LUR approach in quantifying bicyclists' exposure to air pollution in transport microenvironments. This study provides a rationale for encouraging municipalities to develop effective strategies to mitigate the health risks of exposure to local traffic emissions in complex urban bicycling environments.
Keywords
Particulate Matter; Diesel Exhaust; Health; Model; Particles; Asthma; City
Measuring Pedestrian Exposure to PM-2.5: Case of the Seattle, Washington, International District
Bae, Chang-hee Christine; Sinha, Debmalya. (2016). Measuring Pedestrian Exposure to PM-2.5: Case of the Seattle, Washington, International District. Transportation Research Record, 2570, 139 – 147.
Abstract
Traffic-related air pollution is dangerous to human health. Although transportation and land use planning policies often focus on making walking more attractive, there is a lack of research on pedestrian exposure to air pollution levels. This research focused on pedestrian exposure to particulate matter with a diameter of 2.5 mu m or less (PM-2.5) in the International District (ID) adjacent to downtown Seattle, Washington. Several types of equipment were used: (a) a portable nephelometer (Radiance Research M903) mounted on a backpack (arranged by the Puget Sound Clean Air Agency); (b) an AirCasting mobile application (by Habitmap) in a cell phone to record the researcher's location and exposure levels while walking; and (c) a GoPro Hero camera to record visual images of the surrounding built environment, traffic volume, and other activities. The field data were collected three times a day (morning, midday, and evening) for one week in winter (December 31, 2014-January 9, 2015) and one week in spring (March 21-30, 2015) on selected routes in the ID. The study found seasonal and time-of-day variability of exposure levels: there were higher PM-2.5 concentration levels during the winter (57.77 mu g/m(3)) than in the spring (6.99 mu g/m(3)), and higher levels in the morning (25 mu g/m(3)) than in the evening (17 mu g/m(3)). Also, the average PM-2.5 levels of ID data were slightly higher (20.7 mu g/m(3)) than those at the nearest U.S. Environmental Protection Agency monitoring station (19.0 mu g/m(3)). The researchers concluded that the key contributors of pedestrian exposure to air pollution are traffic, construction activities, and smokers on sidewalks.
Keywords
Particulate Air-pollution; Long-term Exposure; Particle Number; Fine; Quality; Health; Pm2.5; Risk; Road
Comparisons of Physical Activity and Walking between Korean Immigrant and White Women in King County, WA
Baek, So-Ra; Moudon, Anne Vernez; Saelens, Brian E.; Kang, Bumjoon; Hurvitz, Philip M.; Bae, Chang-hee Christine. (2016). Comparisons of Physical Activity and Walking between Korean Immigrant and White Women in King County, WA. Journal Of Immigrant & Minority Health, 18(6), 1541 – 1546.
Abstract
Immigrant and minority women are less physically active than White women particularly during leisure time. However, prior research demonstrates that reported household physical activity (PA) and non-leisure time walking/biking were higher among the former. Using accelerometers, GPS, and travel logs, transport-related, home-based, and leisure time PA were measured objectively for 7 days from a convenience sample of 60 first-generation Korean immigrant women and 69 matched White women from the Travel Assessment and Community Project in King County, Washington. Time spent in total PA, walking, and home-based PA was higher among Whites than Korean immigrants regardless of PA type or location. 58 % of the White women but only 20 % of the Korean women met CDC's PA recommendations. Socio-economic status, psychosocial factors, and participants' neighborhood built environmental factors failed to account for the observed PA differences between these groups.
Keywords
Accelerometer; Gps; Korean Immigrant Women; Objective Measures; Physical Activity; Walking; White Women; Nonleisure Time; Leisure-time; Environment; Transportation; Adults; Women; Socioeconomic Status; Time Use; Home Based; Environmental Aspects; Economic Status; Immigrants; Leisure; Socioeconomic Factors; Bicycles; Psychosocial Factors; Comparative Analysis; Minority & Ethnic Groups; Physical Fitness; Regression Analysis; Accelerometers; Travel; Traveltime; Environmental Factors; Recreation; Neighborhoods; Hispanic Americans; Global Positioning Systems--gps; Social Support; Noncitizens; Data Collection; Asian Americans; Psychological Aspects; Households; White People; Asian People; King County Washington; United States--us
Physical Activity and the Built Environment in Residential Neighborhoods of Seoul and Seattle: An Empirical Study Based on Housewives’ GPS Walking Data and Travel Diaries
Park, Sohyun; Choi, Yeemyung; Seo, Hanlim; Moudon, Anne Vernez; Bae, C. -h. Christine; Baek, So-ra. (2016). Physical Activity and the Built Environment in Residential Neighborhoods of Seoul and Seattle: An Empirical Study Based on Housewives’ GPS Walking Data and Travel Diaries. Journal Of Asian Architecture And Building Engineering, 15(3), 471 – 478.
Abstract
This paper is based on a collaborative pilot-study to ascertain the characteristic walking patterns and neighborhood features in residential areas of Seoul, Korea and Seattle, USA. As for sample sites, four case neighborhoods were selected: two from Seoul and two from in and outside of the Seattle-Shoreline areas. As for participants, thirty Korean housewives in Seoul and thirty Korean-American housewives in the Seattle area were selected respectively, and their socio-demographic characteristics, GPS records, and travel diary data for seven days were collected and analyzed. Considering the typical rainy seasons in the two cities, data collections, including the physical activity assessment by GPS devices, were carried out from May to June and from September to October in Seoul, and from July to October in Seattle during the year 2010. Noteworthy research findings include the following: Korean participants in Seoul walk about 2.6 km on average per day, while Korean-American participants in Seattle walk about 400m on average per day. In the case sites of Seoul, 75% of grocery shopping activities happen within the neighborhood by walking, while only 17% of those activities on foot happen in the case sites of Seattle. As for the most walking activity, about 70% of total walking amounts are related to utilitarian walking in Seoul sites, while 50% of total walking are related to recreational walking in Seattle sites. Recreational walking and utilitarian walking occur separately in Seattle sites, while the two walking types are often combined in Seoul sites, which also contribute to more walking amounts and farther walking distances in Seoul sites. This paper empirically confirms the widely held assumptions in part that residents in Seoul, a relatively high-density and high mixed-use city, walk more than those in Seattle, a relatively low-density and low mixed-use city. This paper also recognizes that in the case of both cities, more walking activities occur in the neighborhood built environment, where finely-grained street networks, small lots and blocks, various pedestrian destinations, public transit access, etc are provided in close connection. The amount and frequency of walking activities, as well as the fineness of neighborhood features, however, are remarkably different in the two cities, whose implications deserve in-depth exploration in further studies.
Keywords
Urban Design; Physical Activity; Neighborhood Environment; Objective Measures; Gps Walking Data; International Comparative Study
Do Home Buyers Value the New Urbanist Neighborhood? The Case of Issaquah Highlands, WA
Kim, Jinyhup; Bae, Chang-Hee Christine. (2020). Do Home Buyers Value the New Urbanist Neighborhood? The Case of Issaquah Highlands, WA. Journal Of Urbanism, 13(3), 303 – 324.
Abstract
This study compares Issaquah Highlands’ home prices with those of traditional suburban single-family homes in the city of Issaquah. Issaquah Highlands is a community that was developed using New Urbanism principles. The null hypothesis is that the sale prices of houses in Issaquah Highlands are not different from the conventional suburban neighborhood in the city of Issaquah. The principal database consists of US Census Washington State Geospatial Data Archive, and the King County Tax Assessments. The final dataset contains 1,780 single family homes over the seven-year period from 2012 to 2018 based on sale records throughout the city of Issaquah. This study uses the hedonic pricing technique to assess the impact of New Urbanism on the value of single-family residences. The findings suggest that people are willing to pay a $92,700–96,800 premium (approximately 7.1–12.0 percent of the sales prices) for houses in Issaquah Highlands.
Keywords
New Urbanism; Home Prices; Real Property; Sustainable Development; Spatial Analysis (statistics); Hedonic Pricing Model; Property Value; Smart Growth; Spatial Autocorrelation; Neighborhoods; Databases; Taxation; Spatial Data; Suburban Areas; Census; Prices; Housing Prices; Urbanism; Houses; Willingness To Pay; Residential Areas; Null Hypothesis; Cities; Buyers; Hedonism; Sales; Highlands; Tax Assessments