Projected incremental changes to extreme wind-driven wave heights for the twenty-first century

Area of Science:

• Climate Science
• Oceanography
• Coastal Engineering

Background:

• Global climate change significantly impacts coastal areas through altered wave dynamics.
• Existing coastal impact assessments often overlook the specific contribution of changing wave conditions, focusing primarily on sea level rise.
• Understanding projected changes in extreme waves is crucial for accurate coastal impact and flood risk assessments.

Purpose of the Study:

• To develop a simplified method for integrating projected extreme wave changes into local-scale coastal impact studies.
• To quantify the global-scale changes in the frequency of extreme wave events due to climate change.
• To identify regions most vulnerable to increased extreme wave activity.

Main Methods:

• Utilized non-stationary extreme value analysis to analyze projected changes in extreme wave heights.
• Distilled incremental change signals in wave height data.
• Associated these changes with shifts in the global frequency of extreme wave events.

Main Results:

• Extreme wave heights are not uniformly projected to increase globally; some regions may experience decreases.
• The most significant increases in extreme wave events are anticipated in higher-latitude regions.
• High model agreement indicates a potential doubling of extreme wave events in waters south of Australia, the Arabian Sea, and the Gulf of Guinea by the end of the 21st century.

Conclusions:

• Projected changes in extreme waves represent a critical, yet often underestimated, factor in future coastal flooding and morphological change.
• The developed method offers a practical approach for incorporating wave climate projections into local impact assessments.
• Targeted adaptation strategies are needed for regions identified as high-risk, such as those south of Australia, the Arabian Sea, and the Gulf of Guinea.