The painted houses of Tiébélé, in Burkina Faso, listed as World Heritage by UNESCO, have worrying signs of deterioration linked to climate change. The Moai statues of Ahu Tongariki, on Easter Island, are also threatened by the rise in sea level. These sites are only a few recent examples of the disturbing effects of climate change on many heritage sites.
Tiébélé is home to a royal court dating from the 16th century, adorned with geometric motifs representing the culture, thought and religion of the Kassena people. These sets gradually disappear due to a climate that has become erratic. Easter island preserves nearly 900 statues erected between the 10th and 16th century by the Rapa Nui people, intended to honor their ancestors and their leaders. The Ahu Tongariki ceremonial platform brings together 15 of these sculptures. Located by the sea, the site had already been damaged during the 9.5 magnitude earthquake of which the tsunami had dispersed several statues on the island. The increase in sea level is increasing their exposure to waves today.
In Tiébélé, the inhabitants, in particular the older ones, observe a modification of the climatic rhythm. The Royal Court buildings are more badly. Where it was only raining once a season, precipitation has multiplied and intensified; Conversely, the rains of August, formerly frequent, are rare. This unpredictability complicates the maintenance of the site: “To paint the walls, they must be perfectly dry, but now the rain is unpredictable, and it has already happened that it is raining while we work on catering”explains Anè to Guardian. Drought periods also aggravate erosion. The royal court thus illustrates the direct effects of climate change on heritage and on the Kassena people, whose identity is closely linked to this site. Local chemical pollution further accentuates conservation difficulties.
On Easter Island, according to estimates, the rise in waters could by 2080 threaten 50 sites. Paoa, a member of the Rapa Nui people, has developed a digital twin from the East Coast to simulate the impact of waves. If the statues are not yet directly affected, the projections are worrying.
Moaïs on Easter Island.
The contrast between the countries of the North and those of the South remains marked. The countries of the Sahel, including Burkina Faso, represent only 1 % of global greenhouse gas emissions, but have warming 1.5 times faster than the average. In the absence of sufficient means, these states undergo the effects of climate change without having resources to deal with it.
A UNESCO report published in July alerts on the risks weighing on the Mediterranean World Heritage sites. The study relates to 114 cities, two thirds of which declare that they have already undergone climatic vagaries: high temperatures, droughts, floods or fires. The rise in sea level, estimated between 0.5 and 0.67 meters, is one of the main dangers for coastal sites. The effects will vary depending on the region, but the entire heritage is considered to be vulnerable in the long term.
The impacts are multiple: economic, with an expected drop in tourism, but also cultural. The disappearance of a site involves that of memory, identity and know-how. UNESCO recommends adapting heritage policies to climate change and implementing sustainable preservation strategies in the face of threats such as rising waters or fires.
