High-Water Alerts from Coinciding High Astronomical Tide and High Mean Sea Level Anomaly in the Pacific Islands Region

• Published in: Journal of atmospheric and oceanic technology Vol. 31; no. 12; pp. 2829 - 2843
• Main Authors: Stephens, Scott A, Bell, Robert G, Ramsay, Douglas, Goodhue, Nigel
• Format: Journal Article
• Language: English
• Published: Boston American Meteorological Society 01.12.2014
• Subjects: Anomalies; Astronomical tides; Coastal; Coastal zone; El Nino; Elevation; Forecasting; High tide; Influence; Inundation; Islands; Marine; Mean sea level; Sea level; Sea level anomalies; Sea level forecasting; Tidal waves; Tides; Wind; New Zealand; Pacific Islands; I, Central Pacific, Pacific Ocean Is
• ISSN: 0739-0572; 1520-0426
• DOI: 10.1175/JTECH-D-14-00027.1

A technique to produce high-water alerts from coinciding high astronomical tide and high mean sea level anomaly is demonstrated for the Pacific Islands region. Low-lying coastal margins are vulnerable to episodic inundation that often coincides with times of higher-than-normal high tides. Prior knowledge of the dates of the highest tides can assist with efforts to minimize the impacts of increased exposure to inundation. It is shown that the climate-driven mean sea level anomaly is an important component of total sea level elevation in the Pacific Islands region, which should be accounted for in medium-term (1-7 months) sea level forecasts. An empirical technique is applied to develop a mean sea level-adjusted high-water alert calendar that accounts for both sea level components and provides a practical tool to assist with coastal inundation hazard planning and management.