IMPACT OF VEGETATED INFRASTRUCTURE TO MITIGATE THE URBAN HEAT ISLAND EFFECT IN DHAKA, BANGLADESH
Climate change has a strong negative impact on Bangladesh, though this country has an insignificant carbon footprint. With rapid urbanization, Dhaka City, the capital of Bangladesh, is progressively falling short of sustaining outdoor life due to the Urban Heat Island (UHI) effect, which is one of the most documented phenomena of urban climate change. The urban temperature inside and around Dhaka is about 2.5°C to 7.5°C higher than its surrounding rural temperature and it is found to be highest during the afternoon and night hours. This leads to an increased demand for urban energy resources for cooling and decreased quality of life for the residents of the city. The city possesses only 0.12 acres of greenery and open areas per thousand population, while the National Recreation and Park Association (NRPA) recommends devoting a range between 6.25 and 10.5 acres of total open space per thousand population. A comfortable outdoor temperature can also lead to a comfortable indoor environment, which reduces the energy load of the city. Therefore, this thesis investigates the impact of adding vegetated infrastructure in the city to reduce the heat island effect in the context of Dhaka. For this study, Purbachal, a developing residential area of Dhaka was selected and through ENVI-met software simulation, the impact of adding vegetated infrastructures on the outdoor air temperature and relative humidity was observed by adding vegetated infrastructures on three levels: at street level, on green roofs and in green walls on the buildings. It analyzes which type of intervention can reduce the UHI effect and to which extent. This research reveals that the intervention with urban trees and grass is most effective in mitigating the UHI effect as it reduces the mean air temperature most efficiently during both day and night times as compared to green roofs and green facades. Based on the findings, recommendations have been generated for the tropical city to re-establish outdoor life in Dhaka, where urban spaces will be comfortable, and to reduce building energy needs.
Keywords: UHI effect, Mitigation, Vegetated infrastructure, ENVI-met simulation, comfort
Project Link
https://www.researchgate.net/profile/Tasneem-Tariq
https://scholar.google.com/citations?user=2wvRnWUAAAAJ&hl=en&oi=ao
https://www.linkedin.com/in/tasneem-tariq-75851933/
http://www.usgbc.org/people/tasneem-tariq/0010956148
Advisers/Committee
