Mapping Africa Transformations
Climate
MAPTA-Climate enables users to track the sustainability and resilience of African urban agglomerations. It combines new and innovative spatial data on green spaces, pollution, street networks, and urban forms for nearly 7 200 urban agglomerations with 10 000 inhabitants and above in 54 countries. This data improves our understanding of functional environmental realities and identifies current and future vulnerabilities as well as levers of action for transformative change.
Green spaces deliver ecosystem services that boost cities’ resilience to climate change and strengthen their sustainability. They can attenuate the impacts of extreme weather events such as heat waves, heavy rainfalls, storms and floods, as well as slow-onset risks like drought, land erosion, and landslides. A recent SWAC analysis illustrates that green spaces can help reduce air pollution in urban agglomerations in Africa. In addition to sequestering and storing carbon, they also contribute to water quality and even biodiversity conservation. These spaces are being lost as urban agglomerations become increasingly compact.
The green spaces indicator is the fraction of an urban agglomeration covered by green space. A value of 0.25 means that green space covers 25% of the urban footprint. The colour of the urban agglomeration represents the value of the indicator as of 2021. This data will be updated regularly.
GREEN SPACES
Proximity to green spaces by local populations
Cities with similar absolute levels of green space may exhibit significant variations in terms of the proximity of their populations to these areas. This is important because availability of green space within cities is not enough, people need to live near (i.e. within 300 meters) green spaces of significant size and with trees to really benefit from their cooling effects during heatwaves. The data visualisation below shows a selection of cities across the continent with different green space covers and shares of populations located in proximity to green spaces. An enhanced understanding of these spatial dynamics can help devise targeted strategies to preserve and leverage green spaces in the face of rapid urbanisation and climate change.
Examples such as Accra versus Abuja, Bangui versus Algiers, and Luanda versus Benin City all demonstrate that cities with similar green space coverage can have different proportions of their populations located close to them. Well-distributed green spaces throughout the urban landscape represent one smart strategy to mitigate the effects of extreme heat.
Example: Accra and Abuja. Both urban agglomerations have the same availability of green space, approximately 20% of the urban footprint, but they show drastically different proportions of the population who can benefit from their cooling effects during a heat wave — 16% in Accra and 55% in Abuja. Green spaces could, therefore, offer an important nature-based solution to heatwaves in Abuja, contributing to a more liveable, sustainable, and resilient city. In Accra, the lack of green spaces distributed throughout the city can exacerbate vulnerability to climate change and deteriorate liveability.
Data sources:
This indicator combines two data sources. Africapolis provides the spatial boundaries of the urban agglomerations with at least 10 000 people and with less than 200 metres between buildings. The European Space Agency’s (ESA, 2020) WorldCover provides a land cover map at 10 metres of spatial resolution and uses radar as well as optical satellite imagery. The availability of green space in cities is the sum of the area of three types of land cover (km2) including trees, shrubland, and grassland divided by the total area of the urban agglomeration (km2) as defined by Africapolis.
Citation:
OECD/SWAC (2023), “Green Spaces and Urban Form Dataset”, Mapping Territorial Transformations in Africa (MAPTA), https://mapping-africa-transformations.org/climate (accessed on DD-MM-YYYY).