The Costs of Sea-Level Rise: Coastal Adaptation Investments vs. Inaction in Iberian Coastal Cities

Abstract

Iberian coastal cities are subject to significant risks in the next decades due to climate change-induced sea-level rise. These risks are quite uncertain depending on several factors. In this article, we estimate potential economic damage in 62 Iberian coastal cities from 2020 to 2100 using regional relative sea-level rise data under three representative concentration pathways (RCP 8.5, RCP 4.5 and RCP 2.6). We analyze the expected accumulated damage costs if no adaptation actions take place and compare this scenario to the investment cost of some adaptation strategies being implemented. The results show that some adaptation strategies are less costly than the potential damage under inaction. In other words, it is economically rational to invest in adaptation even in a context of high uncertainty. These calculations are very relevant to inform climate change adaptation decisions and to better manage the risk posed by sea-level rise. Moreover, our findings show the importance of a good understanding of the shape of the sea-level rise and damage cost distributions to calculate the expected damage. We show that using the 50th percentile for these calculations is not adequate as it leads to a serious underestimation of expected damage and coastal risk.

Risk of shoreline hardening and associated beach loss peaks before mid-century: Oʻahu, Hawaiʻi

“…This study is also an example of recognizing that the past is no longer a valid guide to the future, and that analyzing entrenched practices through the lens of science can provide new planning insights before it is too late to apply them. So-called strategic retreat from the shore offers an opportunity for sandy beach survival as well as community revitalization 47 , but will likely come with financial 48 and social challenges 49 . However, action is necessary and likely less costly than inaction even with high uncertainties 48 .…”

“…So-called strategic retreat from the shore offers an opportunity for sandy beach survival as well as community revitalization 47 , but will likely come with financial 48 and social challenges 49 . However, action is necessary and likely less costly than inaction even with high uncertainties 48 . Retreat may not be appropriate or possible for every shoreline, and alternatives based on local parameters should be considered.…”

Relative Sea-Level Changes and Their Impact on Coastal Zones: Past and Future Scenarios from Cases Studies around the World

“…This Special Issue aims to collect contributions to discuss methodological and multidisciplinary approaches to studying relative changes in sea level and the related coastal modification, aiming to reconstruct possible future trends and evaluate the impact of such changes on coastal zones and their amount [1][2][3][4][5][6][7][8][9][10][11][12].…”

“…The third group of articles-contributions by Antonioli et al [8], Scardino et al [9], Abadie et al [10], White et al [11], and Vecchio et al [12]-mainly addressed future coastal scenarios related to the present acceleration in sea-level rise in different morphological contexts around the world. This topical issue was faced at the Mediterranean scale by analyzing LiDAR and Copernicus Earth Observation data to provide estimates of potential marine submersion in 2100 for 16 small-sized coastal plains located in the Italian Peninsula and four Mediterranean countries (i.e., France, Spain, Tunisia, and, Cyprus), all characterized by different geological, tectonic and morphological features, as revealed by Antonioli et al [8].…”

“…Finally, scenarios regarding sea-level variability were reconstructed in the Mediterranean scale by Vecchio et al [12], and extra-Mediterranean scale, i.e., in the North American context presented by White et al [11], taking into account the IPCC predictions and regional tectonic behaviors. Peculiar is the case study presented by Abadie et al [10], in which the potential economic damage in 62 Iberian coastal cities from 2020 to 2100 was estimated using relative regional data on sea-level rises under three representative concentration pathways (RCP 8.5, RCP 4.5, and RCP 2.6).…”