Continental-Scale Assessment of Urban Sprawl in Africa (2016–2024)

Autori

  • Johnny Muhindo Bahavira

Parole chiave:

urban sprawl, africa, image analysis, satellite images

Abstract

This study provides a comprehensive, continent-wide quantification of urban sprawl in Africa between 2016 and 2024 by exploiting the Dynamic World V1 dataset within Google Earth Engine. We computed the dominant land-cover class per pixel for three time windows (2015–2016, 2019–2020, 2023–2024), aggregated built-up area changes nationally, and calculated both absolute and relative growth rates.
Results reveal a net increase of 60,687 km² of built-up land in Africa, driven primarily by Ethiopia, Nigeria, and Kenya in absolute terms, while smaller states like the Central African Republic and Mauritius exhibit the highest percentage gains. Our findings highlight pronounced spatial heterogeneity in urban expansion and underscore the need to integrate socioeconomic and governance indicators to inform sustainable land-use planning across Africa.

Riferimenti bibliografici

Anderson JR, Hardy EE, Roach JT & Witmer RE A Land Use and Land Cover Classification System for Use with Remote Sensor Data. U.S.

Geological Survey , Report 964 (1976).

Brown CF et al. Dynamic World training dataset for global LULC categorization of satellite imagery. PANGAEA (2021). https://doi.

org/10.1594/PANGAEA.933475

Brown CF, Brumby SP, Guzder -Williams B. et al. Dynamic World, Near real-time global 10 m land use land cover mapping. Scientific Data 9,

(2022). https://doi.org/10.1038/s41597-022-01307-4

Deng, X., Shang, S., & Li, S. (2022). Dynamic World: A near real-time global land use land cover dataset at 10 m resolution derived from Sentinel-

imagery. International Journal of Remote Sensing, 43 (10), 3500–3525.

ESA. Comparative validation of recent 10 m-resolution global land cover maps. Remote Sensing of Environment (2024).

Food and Agriculture Organization. (2015). Global Administrative Unit Layers (GAUL) . FAO.

Gorelick , N., Hancher , M., Dixon, M., Ilyushchenko , S., Thau , D., & Moore, R. (2017). Google Earth Engine: Planetary-scale geospatial

analysis for everyone. Remote Sensing of Environment, 202 , 18–27. https://doi.org/10.1016/j.rse.2017.06.031

Iandolo , A., Rossi, F., & Bonomi , M. (2023). Urban sprawl dynamics in West African cities: A remote sensing approach. Journal of Urban Studies,

(2), 213–231.

Li, Q., Qiu, GY, Ma, R., Schmitt, M., & Zhu, AX (2020). Continental-scale urban mapping using Google Earth Engine. Remote Sensing of Environment, 234 , 111482.

Mhangara , P., Gidey , WT, & Manjoo , V. (2024). Monitoring urban sprawl in Southern Africa using satellite imagery and GIS. International

Journal of Applied Earth Observation and Geoinformation , 102 , 102779.

Phiri D. et al. Sentinel-2 Data for Land Cover/Use Mapping: A Review. Remote Sensing 12, 2291 (2020). https://doi.org/10.3390/rs12142291

Schneider, A., & Woodcock, C.E. (2008). Compact, dispersed, fragmented, extensive? A comparison of urban growth in twenty-five global cities

using remotely sensed data. Landscape and Urban Planning, 87 (1), 54–73.

Seto , K.C., Güneralp , B., & Hutyra , LR (2012). Global forecasts of urban expansion to 2030 and direct impacts on biodiversity and carbon.

Proceedings of the National Academy of Sciences, 109 (40), 16083–16088.

Shekhar , S., & Xiong , H. (2008). Encyclopedia of GIS . Springer.

United Nations Department of Economic and Social Affairs. (2018). World Urbanization Prospects: The 2018 Revision . United Nations.

World Bank. (2021). Ethiopia Urbanization Review . World Bank Publications.

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Pubblicato

2025-10-14

Come citare

Bahavira, J. M. (2025). Continental-Scale Assessment of Urban Sprawl in Africa (2016–2024). GEOmedia, 29(3). Recuperato da https://mediageo.it/ojs/index.php/GEOmedia/article/view/2103

Fascicolo

V. 29 N. 3 (2025): GEOmedia 3-2025

Sezione

GUEST PAPER

Licenza

Creative Commons License

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