Photograph - Sky and Mountains

Extreme Wind Speed Variability and Future Adaptation Strategies in Coastal Regions of the Pacific Northwest

Extreme Wind Speed Variability and Future Adaptation Strategies in Coastal Regions of the Pacific Northwest

In December 2006, an intense storm struck southwest B.C., infamously blowing down over 10,000 trees in Stanley Park and resulting in an estimated $9 million dollar restoration cost. Again, in November 2007, another severe storm left 190,000 homes in the Lower Mainland without power. Society’s vulnerability to extreme weather events increases when urbanization and infrastructure development do not consider changing weather patterns. The resulting damages can reach into the millions of dollars, with costs being borne by society through government aid, taxes, or insurance fees.

How will a changing climate affect British Columbia’s regional weather patterns, and therefore the frequency and magnitude of extreme wind events? Much is uncertain about wind behaviour and the consequent impact mechanisms, such as storm surge, tree blow-down, or infrastructure damage. Despite our lack of understanding, we must make forecasts that are as dependable as possible to inform future planning of emergency management. The goal of this research is to examine variability, trends, and adaptation strategies to extreme wind speeds for British Columbia coastal areas and present the results in a straightforward and intuitive manner.

Extreme wind speeds, along with other available weather data (e.g., temperature and pressure), will be correlated with north Pacific climate pattern indexes, such as the Pacific Decadal Oscillation (PDO), Pacific North America pattern (PNA), and the intensity of the Aleutian Low. I will use the correlations in a Bayesian statistical framework (which gives results in terms of probability instead of classical statistical methods that can only provide p-values of hypothesis testing) to forecast future wind speed probabilities, similar to the information presented in a weather forecast. The forecasting horizon for this method will be approximately 1-2 years as this is the current future projection limit of most Pacific Ocean climate indexes.

A local case study will provide relevant details of the statistical forecasting (e.g., thresholds of minimum wind speed necessary for tree blow-down). To aid resource and emergency managers attempting to adapt to changing wind pattern regimes, a risk assessment will evaluate available management options and recommend optimal strategies given wind speed forecasts. Many of the results from this study will be in terms of chance or percentage. Often, people understand these concepts with little difficulty, and an intuitive grasp of the results can improve the willingness of managers and the public to include this information in future discussions and plans. Demonstrating the ability of more accessible formats to easily convey technical information to decision makers and the public is an important step in bridging the gap between science and policy. Interviews with resource and emergency managers will generate potential policy actions to initiate change for communities or service providers who are particularly vulnerable to extreme weather events. An example of such a community is Port Alberni, which recently experienced several major power and transportation emergencies due to severe wind storms and may be at increasing risk if storm activity intensifies or development patterns do not change.

Understanding how our regional climate will change over the coming years is a vital step towards effective local adaptation. Successful strategies for management during severe wind storms will depend on effective communication of problems and solutions to responsible decision makers. If practitioners understand the science driving adaptation strategies, they will be more engaged and better solutions will be the result.

Student Researcher: Brad Griffin (REM)
Project Supervisors: Karen Kohfeld (REM), Andy Cooper (REM)

Project Funding:
NSERC-CFI, NSERC Graduate Fellowship