Projected 21st century changes in extreme wind-wave events

Area of Science:

• Oceanography
• Climate Science
• Climate Change Impacts

Background:

• Projecting future extreme wave conditions is crucial for understanding climate change impacts.
• Previous estimations often lack robust statistical confidence.
• Greenhouse gas emissions are a primary driver of climate change.

Purpose of the Study:

• To estimate global changes in extreme wave conditions by 2100 under projected climate change.
• To enhance statistical confidence in projections of extreme wave events.
• To assess impacts under different Intergovernmental Panel on Climate Change (IPCC) scenarios.

Main Methods:

• Generation of a synthetic dataset using an ensemble of wave models.
• Forcing wave models with independent climate simulation winds.
• Analysis under two Representative Concentration Pathways (RCP4.5 and RCP8.5).

Main Results:

• A 5-15% increase in 1-in-100-year significant wave height (Hs) events in the Southern Ocean by 2100.
• North Atlantic: decrease at low/mid-latitudes (5-15%), increase at high latitudes (≈10%).
• North Pacific: 5-10% increase in extreme significant wave height at high latitudes.

Conclusions:

• The ensemble approach provides enhanced statistical confidence in projected changes of extreme wave heights.
• Significant regional variations in extreme wave height changes are expected.
• Findings highlight the need for adaptation strategies considering future wave climate alterations.