ORIGINAL PAPER Estimation of increase in storm surge damage due to climate change and sea level rise in the Greater Tokyo area Sayaka Hoshino 1 • Miguel Esteban 2 • Takahito Mikami 1 • Hiroshi Takagi 3 • Tomoya Shibayama 1 Received: 16 November 2014 / Accepted: 17 September 2015 / Published online: 23 September 2015 Ó Springer Science+Business Media Dordrecht 2015 Abstract Sea level rise and an increase in typhoon intensity are two of the expected consequences from future climate change. In the present work, a methodology to change the intensity of tropical cyclones in Japan was developed, which can be used to assess the inundation risk to different areas of the country. As a result, the probability of a storm with an equivalent return period in the year 2100 to that of the worst storm in the 20th century overcoming sea defences around Tokyo Bay could be calculated. The risk of higher storm surges, coupled with different sea-level-rise scenarios, highlights how the dykes around Tokyo or Kawasaki could fail unless adaptation measures against climate change are attempted. The cost of adapting to both of these effects by building higher coastal dykes and raising port areas outside them was quantified. Finally, an estimation of the cost of allowing the areas behind the defences to be flooded was also made, clearly showing that the cost of adaptation measures is clearly lower than the cost of inaction. Keywords Storm surge Á Sustainability of coastal defences Á Sea level rise Á Typhoons & Miguel Esteban esteban.fagan@gmail.com Sayaka Hoshino sayahoshi0905@goo.jp Takahito Mikami t.mikami@asagi.waseda.jp Hiroshi Takagi takagi@ide.titech.ac.jp Tomoya Shibayama shibayama@waseda.jp 1 Waseda University, 3-4-1 Ookubo, Shinjuku-ku, Tokyo 169-8555, Japan 2 The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa City, Chiba, Japan 3 Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550, Japan 123 Nat Hazards (2016) 80:539–565 DOI 10.1007/s11069-015-1983-4