African cultural and natural heritage sites in coastal regions are at risk of being damaged or destroyed as sea levels rise. At least 20 percent of the sites that are home to Heritage of Outstanding and Universal Value along the African coast are already at risk from a one-in-100-year extreme sea level event. These include the iconic ruins of Tipasa in Algeria, and the North Sinai archaeological Sites Zone in Egypt.
In a study, published today in the journal Nature Climate Change, a global team of climate risk and heritage experts identified and mapped out the physical boundaries of 284 African coastal heritage sites. They then modeled the exposure of each site under different future global warming scenarios. Dr. Nicholas Simpson from the University of Cape Town’s (UCT) African Climate and Development Initiative (ACDI) was one of the leading contributors to this, the first comprehensive assessment of the risks posed by rising sea levels to these heritage sites.
The researchers found that 56 sites (20 percent) are already at risk from a one-in-100-year extreme sea level event but that, “by 2050, the number of exposed sites is projected to more than triple, reaching almost 200 for high emissions.”
From 2050, at least 151 natural and 40 cultural sites will be exposed to the potential damages of a 100-year extreme sea level event. The model even predicts that, by the end of the 21st century, the coastal heritage sites in some African countries will all be exposed to damage from such extreme sea level events, regardless of the level of greenhouse gas emissions.
“There are several countries which are projected to have all their coastal heritage sites exposed to the 100-year coastal extreme event by the end of the century, regardless of the scenario: Cameroon, Republic of the Congo, Djibouti, Western Sahara, Libya, Mozambique, Mauritania, and Namibia,” wrote the study authors.
And, in the case of the most extreme level of harmful emissions, the model identifies that all coastal heritage sites will also be exposed in Côte d’Ivoire, Cabo Verde, Sudan and Tanzania.
Small island heritage sites are also at high risk of being exposed to the hazards of sea level rise. For example, Aldabra Atoll, the world’s second-largest coral atoll, and Kunta Kinteh Island (The Gambia) could both be exposed to extreme sea level events by 2100 that threaten their very existence.
“This is very concerning because none of these countries currently demonstrate adequate management or adaptive capacity to anticipate or establish heritage protections commensurate with the severity of these hazards,” said the researchers.
The results highlight the importance of climate change adaptation and mitigation responses to protect and reduce the exposure of these iconic heritage sites.
“If climate change mitigation successfully reduces greenhouse gas emissions from a high-emissions pathway to a moderate emissions pathway, by 2050 the number of highly exposed sites can be reduced by 25%. This would be a significant saving in terms of loss and damage from climate change,” wrote the study authors.
“These findings help with prioritizing sites at risk and highlight the need for immediate protective action for African Heritage Sites; the design of which requires in-depth local-scale assessments of vulnerability and adaptation options. Urgent climate change adaptation for heritage sites in Africa includes improving governance and management approaches; site-specific vulnerability assessments; exposure monitoring; and protection strategies including ecosystem-based adaptation.”