Climate change in cities due to global warming and urban effects

Abstract

Urbanisation is estimated to result in 6 billion urban dwellers by 2050. Cities will be exposed to climate change from greenhouse gas induced radiative forcing, and localised effects from urbanisation such as the urban heat island. An urban land‐surface model has been included in the HadAM3 Global Climate Model. It shows that regions of high population growth coincide with regions of high urban heat island potential, most notably in the Middle East, the Indian sub‐continent, and East Africa. Climate change has the capacity to modify the climatic potential for urban heat islands, with increases of 30% in some locations, but a global average reduction of 6%. Warming and extreme heat events due to urbanisation and increased energy consumption are simulated to be as large as the impact of doubled CO2 in some regions, and climate change increases the disparity in extreme hot nights between rural and urban areas.

Enhancing the relevance of Shared Socioeconomic Pathways for climate change impacts, adaptation and vulnerability research

“…Ecosystem impact studies made additional assumptions about technology and deforestation (Golding and Betts 2008;Metzger et al 2008). Population and health studies have used downscaled population (McCarthy et al 2010) combined with expert judgment on adaptive capacity instead of using the socioeconomic assumptions in the SRES (van Lieshout et al 2004). Overall, studies that use the SRES tend to focus more on impacts than on vulnerability or adaptive capacity, possibly because of the paucity of relevant variables.…”

“…Projections of access to public health and health care services and burdens of diseases are relevant for vulnerability and adaptation assessments (McCarthy et al 2010;van Lieshout et al 2004). The SSPs could be enriched with projections based on methods such as the WHO global burden of disease (GBD) approach and the methods included in models, such as GISMO and International Futures (IFs).…”

Decadal variations in the nocturnal heat island of London

“…Although such phenomena are well-understood, urban heat islands (UHIs) can be contentious because of their potential to corrupt estimates of global near-surface temperature trends (Parker, 2010). There are also concerns that UHIs may intensify under future climate conditions, thereby amplifying heat stress on urban residents and habitats (Wilby, 2008;McCarthy et al, 2010).Thanks to the pioneering work of Luke Howard (1833), the UHI of central London has probably attracted more attention than that of any other city. The earliest digitized temperature series for the London area originate from Kew Observatory (1881) (1931).…”

“…Although such phenomena are well-understood, urban heat islands (UHIs) can be contentious because of their potential to corrupt estimates of global near-surface temperature trends (Parker, 2010). There are also concerns that UHIs may intensify under future climate conditions, thereby amplifying heat stress on urban residents and habitats (Wilby, 2008;McCarthy et al, 2010).…”

Using phenology to assess urban heat islands in tropical and temperate regions

“…The examination of the UHI effect and associated aspects is still relevant and important (McCarthy et al, 2010;Oleson et al, 2010), especially because an increasing percentage of the world population -particularly in the tropics -live in (mega)cities (Roth, 2007;Grimm et al, 2008) or are regular visitors to urban areas for inter alia employment or social/recreational reasons.…”