Urban Climate Change

Chapter 2 LITERATURE REVIEW

Urban warming has a serious energy and environmental impact. In recent years, many researches have been carried out: (1) to design, develop and apply efficient mitigation techniques for the urban environment (Hashem 1992; Akbari et al. 2001; Santamouris 2014); (2) to update knowledge and skills on the design and application of urban mitigation strategies (Gartland 2008; Akbari et al. 2016).

2.1 Urbanization and climate change

Urbanization is an intricate and vibrant procedure performing over diverse scales of space and time (Grimm et al. 2008a, b). Nowadays, cities are sprawling increasingly, and urban areas are emerging on average double faster than urban populations worldwide (Angel et al. 2011). During urbanization

Increased urban warmth is not only discovered in the near surface air, but also through all layers of the city (Roth and Chow, 2012). Many studies have been carried out on the relationship between urbanization and climate change. Koo et al (2007) also analysed urbanization effect in climate change over Korea using KMA weather data of 1968-1999. Results showed that urban effect was assessed by 28.7% for temperature growth. Roth and Chow (2012) conducted a historical review of 20 studies since the 1960s to investigate Singapore’s urbanization effects on thermal environment, and found that urban development had clear influence on air and surface temperature models. Kug and Ahn (2013) studied on impact of urbanization on recent temperature and precipitation trends for the period of 1975-2005 in the Korean Peninsula, and found that there existed a positive correlation between urbanization and temperature rise, and urbanization enhanced regional precipitation

To date, many studies focus on the use of in situ data, which have a high temporal resolution with long years’ documented data, but not good spatial resolution (Hung et al, 2006). Satellite thermal data, on the other hand, have higher spatial coverage and provide information on the UCL heat island. However, these data have not been widely used due to the complex interactions of TIR radiations with the atmosphere and urban surfaces. Voogt and Oke (2003) reviewed thermal remote sensing of urban climates, and found it was slow to advance beyond qualitative description of thermal patterns and simple correlations. One difficulty was the complexity in using qualitatively based land use data to describe urban surface rather than describing more fundamental