Urban Heat Islands: What Are Urban Heat Island?

What are urban heat islands?

Urban heat is a term used to describe an occurrence where built up areas are hotter than the rural areas they are in proximity to. As urban areas become more and more developed, changes occur in the landscape. Infrastructure replaces open land and vegetation. Surfaces where heat used to be absorbed are replaced by surfaces that are dry and don’t absorb heat. Changes like theses cause urban regions to become warmer than rural regions, this forms, in a sense, an “island” of hot temperatures in the landscape. The heat is created by energy from the daily activities of people in big cities. These activities include commuting (cars, buses, and trains), and recreational activities.

Causes of urban heat

Urban heat islands can manifest in

Effects of urban heat

Increased energy consumption: Increased temperatures during summer in cities increases the demand for energy as many people would want to air condition their properties. Studies have shown that a spike of energy demands occurs for air conditioning or cooling , this spike is between 1.5 to 2 per cent for every 0.6°C increase in air temperatures 20 to 25°C showing us that the community requires about 5 to 10 per cent more electricity to cope with the urban heat effect.

This means the increased demands for cooling or air condition during summer contributes to higher energy bills and, the resulting demand for air conditioning can overload systems which can lead to power outages and blackouts.

The increase in air conditioning usage will also increase the amount of heat released into the atmosphere, this will also contribute to air pollution, as more greenhouse gas emissions are being released. This negatively impacts air quality which can result in an increase of urban smog.

This smog negatively affects health. The increase in temperature and air pollution can lead to problems such as asthma, the increased spreading of vector-born disease, heat stroke as well as childhood