The Green and Red Trade-offs: Evidence of Rising Temperatures and Health Risk in Greater Accra Metropolitan Area (GAMA), Ghana

Keywords: urban built-up environment, land cover change, land surface temperature, urban heat, health, urbanization
Abstract Type: Virtual Paper Abstract

Abstract

Globally, cities are rapidly expanding, generating land surface heat from urban land-use, which poses posing serious health risks. This phenomenaon is exacerbated by climate change in low-income regions such as Africa that experience rural-to-urban migration. This study explores the spatio-temporal trends of land surface temperature, urban built-up and vegetation cover change in GAMA, from 1991 to 2021. The study used Landsat satellite data to perform land use and land surface temperature change analysis and conducted online survey across 56 communities in GAMA to examine the patterns and magnitudes of LST, land-use landcover change and how LST quintiles relate to poverty and human health risks. The study found that urbanization in GAMA is trading greens for heated surfaces and impacting more on the health of poorer communities of GAMA. Between 1991 and 2021, the mean LST increased from 27 °C to 33 °C at an annual rate of 0.2 °C. For the same period, the built environment increased by 849.6 km2 (258.7%) at an annual rate of 8.6%, while the vegetation cover decreased by 846.3 km2 at 2.5% per annum. The forest community of Kisseman, the populous community of Dansoman and the harbour city of Tema corresponded to the first, fourth and fifth quintiles of LST-poverty relationship. Common health risks reported included discomfort from hyperhidrosis, headaches, dehydration, thirst and skin rashes. These results call for immediate climate actions on extreme heat and creation of sustainable and resilient cities.