Increasing Urbanisation and the Role of Green Spaces in Urban Climate Resilience in Africa

Abstract

Africa's urban population presently totals 439 million people or forty per cent of its total population, a share that is expected to rise to 1.1 billion or 56 per cent by 2050. Urbanisation is constituted not only in terms of demographic and land expansion, but also in the transformation of the environment and social conditions in the growing urban centres. As the world's shelter and economic hubs, urban areas account for more than seventy per cent of global greenhouse gas emissions. Alongside numerous cli- mate change challenges, urban areas are also characterised by warmer temperatures due to the urban heat island effect as well as rising inequality and poverty. Achieving resilient urbanisation is therefore a multifaceted issue. In this chapter, we discuss Af- rican urbanisation and urban green spaces in the context of urban climate resilience. Combining case studies across cities in Africa, we found that urban areas are growing at an annual rate of five hundred hectares, an expansion occurring at the expense of agricultural and natural land cover. Together with increasing consumption of fossil fuels as well as growing infrastructural deficiencies, waste disposal sites, and industrial facilities within ecologically sensitive zones, African cities are becoming increasingly vulnerable to the perils of climate variability and change. The effects of urban heat islands, poor air quality, flash floods, heatwaves, increasing public health hazards, rising regional mean temperatures, and droughts will escalate further if African urbanisation proceeds at its current pace without any intervention. On the other hand, the culture of creating and preserving green spaces such as street trees, sacred groves, cemetaries, public parks, gardens in residential lots, vegetation in institutional compounds, and urban farm- and grasslands by urban authorities and private landowners is a promising indicator that cities can be resilient to the local impacts of changing climatic conditions through the adoption of adequate adaptation and mitigation measures. For instance, urban green spaces in the Ghanaian city of Kumasi store as much as 168- 1,737 tons CO2 sequestered from the atmosphere per hectare. The management of Africa's urban green spaces, however, poses challenges distinct from those facing cities in the Global North. The weakness of enforcing institutions, despite the occasional existence of appropriate legislation, as well as the potential for society to endorse either favourable or detrimental changes concerning green spaces are key in urban green space management. It is important to either amend or, where necessary, enact urban environmental policies to help make an increasingly urban Africa more climate- resilient.