Assessment to 2100 of the effects of reef formation on increased wave heights due to intensified tropical cyclones and sea level rise at Ishigaki Island, Okinawa, Japan. Issue 3 (3rd July 2021)

• Record Type: Journal Article
• Authors: Hongo, Chuki; Kiguchi, Masashi
• Is Part Of: Coastal engineering journal. Volume 63:Issue 3(2021)
• Page Start: 216
• Page End: 226
• Publication Date: 2021-07-03
• Subjects: Green infrastructure -- reef formation -- wave height -- Acropora digitifera -- Acropora hyacinthus; Coastal engineering -- Periodicals; Coasts -- Periodicals; Hydraulic engineering -- Periodicals; Coast changes -- Periodicals; Shore protection -- Periodicals; Coast changes; Coastal engineering; Coasts; Hydraulic engineering; Shore protection; Periodicals; 627.58
• DOI: 10.1080/21664250.2020.1870075
• Languages: English
• ISSNs: 2166-4250

Abstract

ABSTRACT: Tropical cyclones (TCs) cause enormous damage to unprotected coastal areas. Healthy coral reefs can reduce this damage and are low cost and maintenance free. We use a wave simulation model to estimate changes that will occur by 2100 in wave height on a coral reef for a healthy reef and a degraded reef under variable TC wave conditions and sea level rise at Ishigaki Island, Ryukyu Islands, Japan. Moreover, we estimate the potential reef production rate based on analysis of a Holocene reef core, and indicate possible reef restoration and conservation strategies, including a selection of appropriate coral communities for transplantation, if the future reef is degraded. Our findings indicate that the significant wave height at the reef flat will increase from 1.69 m at present to a maximum of 3.00 m for degraded reefs and a maximum of 2.63 m for healthy reefs under intensified TCs by 2100. The value of potential reef production rate required for healthy reefs by 2100 is 3–10 kg CaCO3 /m 2 /y. If the reef is degraded by global and local impacts, planning for reef restoration and conservation such as direct coral transplantation of Acropora digitifera and Acropora hyacinthus may be considered.