Thirty-year projection of coastal evolution on Tuamotu islets

French Polynesia has submitted a proposal form for an action on the Tuamotu archipelago, carried out by the Direction de la Construction et de l'Aménagement, as part of the GO Facility, with the aim of adapting coastal development strategies to coastline recession on 6 Tuamotu atolls (Rangiroa, Hao, Manihi, Makemo, Anaa, Fakarava) as well as on Pointe Vénus at Mahina on the island of Tahiti, integrating on the one hand existing developments (and their consequences, positive or negative) and on the other hand the impacts of climate change (rising sea levels but also major cyclonic events).
The ultimate aim is to delineate the areas currently exposed to coastline retreat up to a 30-year horizon (short-medium term) in order to adapt development rules or at least their main principles.
The mission's specific objectives are to gather existing data and information on the functioning of the coastline, the past and present positions of the coastline and the evolution of the coastline and coastal strip of these atolls and Pointe Vénus; to characterize the causes of current and future erosion, taking into account the impact of climate and anthropogenic change on hydrosedimentary dynamics; to map the area of coastline evolution up to 30 years for these atolls and Pointe Vénus; gather information on the historical and current occupation of the coastline of the atolls and Pointe Vénus; assess local perceptions of coastal hazards, and in particular the phenomenon of coastline retreat, and the acceptability of associated adaptation measures; all this to formulate development and adaptation recommendations for areas exposed to this projected retreat in 30 years' time.