The adverse effects of climate change are a global concern, and global warming is increasingly threatening urbanized areas. While average temperatures are increasing across the globe, highly urbanized areas are notably hotter than their rural counterparts. The culprit is a phenomenon called the Urban Heat Island (UHI) effect. The materials used in ground covers and other construction absorb and trap the rays of the sun, subsequently raising the surface level temperature. The expansion of the built area produces an environment with less vegetation and most natural surfaces covered by pavement or buildings. The UHI effect has serious socio-economic consequences for those living in urbanized areas, and cities located in developing countries are particularly susceptible to the negative impacts. Mitigating the effects of UHI through informed urban design and public policy is crucial as developing countries continue to expand their cities. The primary goal of this research is to define the specific challenges that cities in developing countries face from the UHI effect, and to identify effective and practical mitigation strategies for developing countries.
The author conducts a literature review of secondary sources to achieve the goals of the study. The review focuses on peer-reviewed academic studies; however, relevant non-peer-reviewed resources were also included. The thesis is organized in sections that explore topics such as a discussion of the UHI effect and its causes, a description of major socio-economic impacts of UHI, a discussion of the general vulnerability of cities in developing countries to climate change, and a discussion of particular factors that make cities in developing countries vulnerable to the impacts of UHI.
Data suggests that the UHI effect negatively affects urban areas and creates a vicious cycle of poor living conditions for urban residents. Increased temperatures caused by UHI increases energy use in urban areas and, at times, can overwhelm regional power grids. Increased energy use leads to increased pollution as well. The poor air quality can then can magnify respiratory illnesses while high temperatures spur heat-related health problems. The UHI effect also affects urban areas economically, as high temperatures decrease worker productivity and create economic losses.
Cities in developing countries face a unique set of challenges that make them more susceptible to the negative impacts of UHI discussed. Factors such as disproportionate dependence on weather-variable industries such as agriculture, poor geographic location, rapid urbanization coupled with the loss of green space, and preexisting water struggles exacerbate the effects of UHI.
To lessen the severe and undesirable effects of UHI, environmentally-friendly changes to urban developments must be made. Cities can increase plant more trees and develop more urban green spaces like parks to combat threats to air quality. City planners can also implement eco-friendly designs in the existing built environment, including vegetated roofs, vegetated facades and walls, “cool” building materials that reflect solar radiation and dissipate heat in construction, and “cool” roofs and pavement. In conjunction with urban design strategies, local and state government need to implement policies to assist the implementation of these strategies.
Some strategies are challenging to implement in cities in developing countries because of existing structural and societal barriers; poor governance, insufficient funding, lack of awareness and communication among governance and residents, and potential differences in attitudes all present barriers to developing countries. Although more difficult to implement, these strategies can be modified to more appropriately suit the needs of the environment and the developing countries that require sustainable solutions.
Climate change is not going anywhere anytime soon, so it is impertinent to understand how its consequences, like UHI, will impact cities now and in the future. Inaction to lower temperatures will result in low quality of life for the inhabitants of urban areas and will be worse for those in urban areas of developing countries. This research further highlights areas in academic literature that are lacking and need further research or development. These gaps include the sparse literature on the connection between UHI and particular vulnerabilities of cities in developing areas. Further research on this particular topic will certainly be valuable in the future.
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