Redefining design wave conditions in the Gulf of Mexico under a changing climate

Climate change is expected to increase both the frequency and intensity of major tropical cyclones, raising the risk from extreme ocean waves. Reliable estimation of these waves is essential for maritime-structure design, yet assessments that rely solely on historical records cannot capture the ongoing non-stationary changes already under way. We introduce a physics-based Gulf of Mexico–wide framework that couples ∼20,000 synthetic tropical cyclone events with a third-generation spectral wave model explicitly resolving present (1980–2010) and future (2070–2100, SSP5-8.5) climates using five CMIP6 GCMs. This synthetic approach overcomes the dual limitations of short observational records and coarse GCM resolution. Results show that the 100-year significant-wave height derived from present synthetic events already exceeds API values based on historical data by ∼2 m, and that this design metric is projected to increase by up to 30 % by the late century in the northern Gulf. Such changes imply that structures designed today under stationary assumptions will face a higher probability of encountering their design wave during service. These findings underscore the need for robust present-day design databases and the integration of non-stationary wave climate projections into future design frameworks to safeguard maritime assets and ensure long-term resilience.