In this paper, 64-year tropical cyclone (TC) data in the Northwest Pacific (NWP) were analyzed to predict extreme wind speed under the background of climate change. The extreme value theory is presented in order to obtain extreme wind speed with different return periods in both stationary and non-stationary processes in the NWP. Results show that the non-stationary extreme wind speed of 50-year return periods is 3.2% higher than the stationary one in the NWP. As a result, it is proposed that the non-stationary effects of long-term variation in atmospheric general circulation should be considered in the offshore engineering standard or criterion revision.
The NWP is the place where the most frequent and intense TCs occur among the global sea areas, and the reliability of offshore structures in this area are heavily affected by TCs, which may bring strong winds and corresponding huge destructive waves inducing great damage of social property and economic. On the other hand, with the development of the human economy, the climate change induced by greenhouse gases (e.g. CO2 and CH4 et.al.) emission has become an unchangeable fact. The annual report released by IPCC (Intergovernmental Panel on Climate Change) in 2007 persuasively confirmed that the global temperature has risen by 0.74°C in the past one hundred years (1906–2005). For example, when the hurricanes of Katrina which is the most destructive natural disaster in American history (Demirbilek, 2010; D.H. Levinso et al., 2010)and Rita were haunting about the Mexico gulf in 2005, the 167 offshore platforms and 183 oil pipelines were destroyed, resulting in 40 percent oil production of Gulf of Mexico interruption. In the South China Sea (SCS), a great many of offshore structures were also threatened by super strong typhoons such as Zhenzhu in 2006.