Ocean wave heights measured by buoys along the U.S. Atlantic coast document an increase during the summer months when hurricanes are most important to wave generation. Wave heights greater than 3 meters, which can be attributed to specific hurricanes, have increased on average by 0.7–1.8 meters in the past 30 years, with the southernmost buoy that is offshore of Charleston, S.C., experiencing the highest rate of increase. The most extreme hourly averaged wave heights generated by major hurricanes have increased from about 7 meters early in the records of the buoys to more than 10 meters during the most recent decade. This increase in wave heights can be attributed in large part to a progressive intensification of the hurricanes, which Emanuel [2005] has documented through his analyses of hurricane wind speeds.