New research by the University of Delaware and Stanford University shows that an army of offshore wind turbines could reduce hurricanes’ wind speeds, wave heights and flood-causing storm surge. The findings, published online this week in Nature Climate Change, demonstrate for the first time that wind turbines can buffer damage to coastal cities during hurricanes. Study co-author Cristina Archer, associate professor in the University of Delaware’s College of Earth, Ocean, and Environment and Stanford’s Mark Jacobson previously calculated the global potential for wind power, taking into account that as turbines are generating electricity, they are also siphoning off some energy from the atmosphere. They found that there is more than enough wind to support worldwide energy demands with a negligible effect on the overall climate. In the new study, the researchers took a closer look at how the turbines’ wind extraction might affect hurricanes. Unlike normal weather patterns that make up global climate over the long term, hurricanes are unusual, isolated events that behave very differently. Thus, the authors hypothesized that a hurricane might be more affected by wind turbines than are normal winds. Using their sophisticated climate-weather model, the researchers simulated hurricanes Katrina, Isaac and Sandy to examine what would happen if large wind farms, with tens of thousands of turbines, had been in the storms’ paths. They found that, as the hurricane approached, the wind farm would remove energy from the storm’s edge and slow down the fast-moving winds. The lower wind speeds at the hurricane’s perimeter would gradually trickle inwards toward the eye of the storm. “There is a feedback into the hurricane that is really fascinating to examine,” said Archer, an expert in both meteorology and engineering. The highest reductions in wind speed were by up to 87 mph for Hurricane Sandy and 92 mph for Hurricane Katrina. According to the computer model, the reduced winds would in turn lower the height of ocean waves, reducing the winds that push water toward the coast as storm surge. The wind farm decreased storm surge, a key cause of hurricane flooding, by up to 34 percent for Hurricane Sandy and 79 percent for Hurricane Katrina.