The Study of the Economic Effects for an Island of a Disruption in Commercial Links with the Mainland: The Case of the Island of Yeu

Assessing the impacts of climate change is essential to making informed decisions about protective planning against climate risks. These impacts can be direct (resulting from the physical effect of the hazard on assets) or indirect (arising from direct impacts). The evaluation of direct damages is relatively consensual and is usually conducted through damage stage-damage functions. However, the evaluation of indirect damages creates significant debate within the scientific community. This article proposes a volumetric analysis of the indirect impacts of sea level rise on insular economic activity. One of the characteristics of the Island of YeuÕs economy is its strong dependence on imports from the mainland. The method presented here estimates the concrete effects of a disruption in maritime connections between the island and the mainland for each economic entity of the territory, defining thresholds of impact ranging from stockout to generalized shortages across the island. This research also allows us to observe certain aggravating factors of impacts, particularly those related to the tourism economy. Results show, for example, that the hotel and catering sector is the most vulnerable to this risk and could experience a stockout after five days without island resupply. This result leads to a risk of shortages, exacerbated during the summer period by the sharp increase in the number of people on the island. The work presented leads us to consider volumetric analysis of indirect impacts as complementary to monetary evaluation methods, since it produces results at the micro- and meso-economic levels of a radically different nature, enabling the identification of levers of action to better protect the assets of a territory.