Projection and detection of climate change impact on fatigue damage of offshore floating structures operating in three offshore oil fields of the North Sea

Abstract

Fatigue damage of offshore floating structures is a long-term cumulative process, which is mainly attributed to ocean waves. The natural variability and human-induced climate change may affect the wave climate and consequently result in the change of fatigue damage. This paper aims to investigate the effect of climate change on the fatigue damage of offshore floating structures operating in three offshore oil fields of the North Sea (Alma/Galia, Pierce, and Rosebank oil fields, located in 56.2° N/2.8° E, 58° N/1.45° E, and 61° N/4° W latitude/longitude). Then it can detect whether human-induced climate change has a considerable impact on fatigue damage. Therefore, firstly the natural variability of wave height and fatigue damage was investigated through 30-year control simulations by coupling wave models to climate models, ignoring the effect of human activities. After that the sea states and annual fatigue damages were projected in three decadal periods (2011–2020, 2051–2060, and 2091–2100) based on widely recognized climate scenarios including the greenhouse gas emission trajectories. The effect of human-induced climate change has been detected, and it has been found that the higher the emission, the less the fatigue damage in considered floating structures in the North Sea. In addition, although wave height is the dominant wave characteristic in fatigue calculations, the change of other wave characteristics should also be considered to improve the quality of fatigue designs.