The Urban Heat Island Effect and ways to
The Urban Heat Island Effect and ways to mitigate it in regards to Los Angeles Ji Hyun Park* and Ji Sun Park** *Crean Lutheran High School **University of California, Riverside
Introduction • Urbanization to Metropolitan Cities • Shifts from rural areas to an area with densely populated urban core with less populated surrounding territories
Negative Impacts of Metropolitan areas Heat Production Reduced Vegetation
Negative Impacts of Metropolitan areas Increased Heat Absorbance
Environmental Impacts (Shahmohamadi et al. 2010; US EPA, 2008) Reduced Air Quality and Increase in Greenhouse Gases (US EPA, 2008)
Impacts on Humans Increased temperature contributes to health issues (US EPA, 2008) - respirator y difficulties - heat cramps and exhaustion - non-fatal heat stroke
Microclimate Change Figure 1: Variations of Surface and Atmospheric Temperatures.
Objective • To study the Urban Heat Island effect occurring in multiple cities in the United States, specifically that of Los Angeles
Table 1. Change of Temperatures of urban cities and their surrounding areas. (Zhao et. Al, 1914)
Figure 2: Temperature differences between cities and surrounding areas Color of the dot indicates the amount of annual mean precipitation. Red is less than 20 inches; Green is between 20 and 43 inches; Blue is more than 43 inches. Size indicates temperature differences between cities and surrounding areas. (Zhao et. Al, 1914)
Los Angeles
Figure 3: Emergency Room Visits for heat related illnesses by Zip Code in Los Angeles.
LA City Initiatives • Cool. Seal
Other City Initiatives • Green Roof/Cool Roof - In 2008, New York City law was enforced to have 75 percent of the roof area be covered in reflective, white coating - In Bronx, mixture of green and cool roof
Figure 4: Comparison of black and white roof temperatures on test site on top of the Museum of Modern Art in Queens, New York Credit: Gaffin et al.
Other City Initiatives • Cheonggyecheon – Seoul, South Korea
Cheonggyecheon
25 TEMPERATURE(Co) 20 15 10 5 0 Before After Figure 5: Average Surface Temperature of Seoul, South Korea Before (2000) and After (2010) the revitalization of the Cheonggyecheon.
22 TEMPERATURE(Co) 21, 5 21 20, 5 20 Before After Figure 6: Average Air Temperature of the Cheonggyechon before and after Revitalization.
26 24 o Temp. (co) 25 23 22 21 20 river 60 120 180 240 300 360 420 480 540 600 Distance(m) Figure 7: Temperature differences based on distance from the river. (Myung, 2009)
Los Angeles River • Flowing River in the Heart of Los Angeles
30 Number of plants 25 20 15 10 5 0 S 1 S 2 Location S 3 S 4 Figure 8: Number of plants per location on the Los Angeles River. S 1 refers the Big Tujunga Creek; S 2 refers to the Hanson Dam; S 3 refers to Taylor Yards; S 4 refers to the Olympic Blvd.
: ss m H: m tt : s m s tt m H: : ss m tt m H: : ss m tt m H: : ss m tt m H: : ss m tt m H: : ss m tt m H: : ss m tt m : ss tt m H: Air temperature(o. C) 50, 0 45, 0 40, 0 35, 0 30, 0 25, 0 20, 0 Site 2 15, 0 Site 4 10, 0 5, 0 0, 0 Time Figure 9: Comparison of the two locations in the Los Angeles River. Site 2 refers to Hanson Dam; Site 4 refers to the Olympic Blvd.
Conclusion • Heat Island is present in multiple different cities, including Los Angeles • There are several initiatives to mitigate the Heat Island Effect • One of the Initiatives, Cheonggyecheon restoration in Seoul is a Success • River’s temperature decreasing effect only nearby vicinity • Plants give shade and coverage, playing an important role on decreasing temperature
Suggestions by Other Researchers • Planting vegetation/greeneries • Cool/Green Roof • Cool Seal on pavement
Suggestions • Revitalization of Los Angeles River
Suggestion • Lining the streets with small canals like Germany’s Freiburg Bächle (Gutters) and South Korea’s Jeonju/Gwanghwamun Mulgil (Water Path) Jeonju Freiburg Gwanghwamun
Reference • U. S. Environmental Protection Agency. (2008). Reducing urban heat islands: Compendium of strategies. Draft. • Zhao, Lei, et al. (2014) Strong Contributions of Local Background Climate to Urban Heat Islands. Nature News, Nature Publishing Group. • Dubar, Biran. (2012) Bright is the New Black: New York Roofs Go Cool NASA, NASA Web. • Shahmohamadi P. , Che-Ani A. I. , Ramly A. , Maulud K. N. A. , Modh-Nor M. F. L (2010) Reducing urban heat island effects : A systematic review to achieve energy consumption balance. International Journal of Physcial Sciences Vol. 5 • Myung, Soojung. (2009) A Study on Strategies to Mitigate Urban Heat Island Effects as Part of Climate Change Adaptation in Urban Areas. Korean Environment Institute. • Kim, Kyung Tae and Song, Jaemin. (2015). The Effect of the Cheonggyecheon Restoration Project on the Mitigation of Urban Heat Island Effect. Journal of Korean Planning Association Vol. 50, No. 4. • Botkin, D. and Keller, E. 1995. Environmental science: Earth as a living Planet. John Wiley and Sons Inc.
Acknowledgement • I would like to thank the Heal The Bay team for giving me the opportunity to present my research and Meredith Mc. Carthy for setting the time up and connecting me with the team! • I also would like to thank my sister, Ji Sun Park, for working with me in this research and although she was unable to come today, she played an important role in the formation of this research project. • Finally, I would like to acknowledge and thank the support of my parents for helping me along the project and providing me with the help and the encouragement to finish this project.
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