After the 9/11 attack in New York City, structural engineer and architect Guy Nordenson ’77 helped determine the structural integrity of more than 400 city buildings. For several years he has also advocated preparing the area for future natural disasters such as storm surges. Now he’s a co-author of a new study, “A Stronger, More Resilient New York,” commissioned by New York City Mayor Michael Bloomberg in the wake of Hurricane Sandy. The document’s recommendations for more than $20 billion in improvements include constructed barriers such as floodwalls and levees, plus natural measures such as restoring beaches and marshes. The Alumni Association’s Slice of MIT blog recently posted about Nordenson, who is a professor of architecture at Princeton University.