Metocean Conditions in Future Hurricane Environments

Abstract

The offshore energy industry in the Gulf of Mexico is exposed to substantial hurricane risk. The plausible scenario of the hurricane climate changing in response to climate change could severely impact the industry, yet understanding changes in hurricanes on regional scales is challenging due to the small number of events and high variability. For impacts, loading on facilities is a complex function of wind, waves and ocean currents. To understand future loading scenarios, it therefore becomes necessary to account for these multiple load drivers. An approach is developed to assess future changes to metocean (Metocean is an offshore engineering term used to describe combined meteorological and oceanographic conditions) conditions in hurricane environments using physical modeling that captures relationships between wind, waves, and current. For a set of nine historical Gulf of Mexico hurricanes, the effects of the hurricane wind fields on ocean waves and currents are simulated using analysis winds to drive a wave model and a regional ocean model. The generalized extreme value distribution describes wind, wave height, wave period, and surface ocean current well. In addition, significant wave height is significantly correlated with wave period and wind speed in hurricane environments. The effects of the hurricane wind fields are simulated again with modified hurricane wind fields consistent with future climate scenarios, while keeping the current climate ocean forcing fixed. Under the future scenario of 10% increase in wind speed and 10% reduction in storm size, the distributions shift to