Climate-driven Impacts in Ports on a Tectonically Active Coast Under Mid- and End-of-century RCP 8.5 Scenario

Abstract

Economic costs due to operational downtime and wave overtopping under the RCP 8.5 scenario are evaluated at 7 Chilean ports located on a tectonically active-coast. Wave statistics for a historical period (1985-2004), mid-century (2026-2045) and end-of-century projections (2081-2100) are computed with a Pacific-wide model, forced by wind fields from six General Circulation Models. Offshore waves are then downscaled to each port, where downtime is computed by comparing wave heights with vessel berthing criteria. The difference in downtime between the historical and projected periods is attributed to climate change. While changes in offshore wave climate will be moderate and spatially smooth in the region, some ports will reduce and others increase downtime for mid-century projections due to local effects. By the end-of-century, however, all ports will experience downtime reduction. Additionally, by mid-century, overtopping will increase in northern ports as a combination of extreme waves and sea-level rise (SLR), while in southern ports it will be slightly reduced due to milder waves. By the end-of century, overtopping will increase in the whole region, mainly driven by SLR. Overtopping rates, however, are significantly altered by coseismic uplift/subsidence which may occur during the design-life of coastal works. Adaptation measures are finally proposed.