Satellite imagery from Nov. 2 showed that Sandy’s remnant clouds continue to linger over Canada and the northeastern U.S.

Do costly seawalls provide a false sense of security in efforts to control nature? Would it be better to focus on far less expensive warning systems and improved evacuation procedures? A father-son team have developed new strategies to defend society against natural disasters like Hurricane Sandy and the effects of climate change. The approach, which considers costs and benefits while identifying the best solution, is based on a mathematical technique called optimization.

Climate change is affecting overall weather patterns, scientists say, and could affect water availability in California.