West Cliff Drive, like all of the California coastline, is threatened by continuing erosion. Erosion is expected to significantly increase as sea levels rise and storms intensify. One challenge to adaptation planning is the uncertainty associated with the rate and elevation of sea level rise at future points of time, critical to the question of what to do and when. What to spend on what strategy for the best return on investment? A recent report published by the Center for the Blue Economy and partners has some answers.