The Urban Heat Island (UHI) is defined as the temperature difference between densely built-up urban areas and surrounding suburban ones. UHI is caused by a multitude of factors including both spatial factors; for example, features of landform surfaces and surface characteristics, and temporal ones, linked to yearly, seasonal, diurnal, and nocturnal air temperatures. A comprehensive overview of current literature and critical analysis of UHI is provided in this paper. It aims to assess the environmental and social impacts of phenomena in different climate regions, and how some of these factors can be used as a design tool to associate and estimate renovations and policy-making strategies. Then it discusses various approaches for modeling UHI intensities on different scales. The paper concludes with a classification of potential mitigation strategies including their advantages and disadvantages as well as their suitability for different climate regions. Mitigation strategies are categorized based on their impacts on:
changing anthropogenic factors
increasing the radiative properties of materials,
modifications to urban geometry
decreasing anthropogenic heat
increasing green and blue spaces,
lowering greenhouse gas emissions.