Approach to Estimating Near-Surface Extreme Wind Speeds with Climate Change Considerations

Windstorms, in an average year, are responsible for the most insured losses in the United States. Despite the significant losses, estimation of peak wind loading on structures remains difficult due to the inherent uncertainties in the estimation process. These uncertainties have usually been grouped into what has been termed the wind loading chain, which includes elements from the wind climate (e.g., storm type, wind directionality), terrain (e.g., roughness length, surrounding buildings), and aerodynamic (e.g., building shape, orientation) and dynamic (e.g., stiffness) effects. A lack of knowledge in a particular link (i.e., weak link) of the chain can lead to the unreliability of the entire structure. Current projections suggest the frequency and intensity of some environmental extremes, including wind speeds, will be affected due to a changing climate, thereby adding another layer of uncertainty in the wind climate link regarding the treatment of future (i.e., design) extreme wind loading for structures. This paper develops an approach for uncertainty characterization of extreme wind speeds with a worked example applied to nonhurricane events. The objective of this paper is to improve understanding of the wind climate and terrain links in the wind load chain by identifying, quantifying, and attributing uncertainties in these links including those from climate change. This objective will be achieved by (1) identification of new data-driven sources to better understand uncertainties; (2) development of a probabilistic approach to incorporate data and its associated uncertainties into the extreme wind speed estimation process, including projections of extreme winds in future climate states; and (3) quantification and attribution of uncertainties to the links of the chain considered.