Impacts of climate change: Challenges of flooding in coastal East Asia

Currently, more than half of the Asian population live in coastal areas, especially in vulnerable deltas and coastal cities (Fuchs et al. 2011; Woodroffe 2010). More than 325 million inhabitants are living in coastal low-lying flood prone areas in East Asia alone (McGranahan et al. 2007). Many of these areas are predicted to be vulnerable under near future climate change (e.g., sea level rise), with millions of people and their economic assets exposed to floods and storms (Ward et al. 2011). Seto (2011) projected that in the next few decades, most population increase will take place in the exposed deltas, estuaries, coastal zones and coastal cities of Asia (and Africa) due to better employment and education opportunities. Rapid socioeconomic trends amplify the possible consequences of future floods, with increasing urban populations and greater financial capital invested in the flood-prone coastal zone. Hanson et al. (2011) found that more than 20 cities in East Asia will be highly exposed to coastal flood risks in the 2070s. Wilby and Keenan (2012) expect the frequency, intensity and duration of extreme precipitation events to increase as a result of climate change. Many Asian coastal areas are suffering from an increasing frequency of typhoons, rainstorms and storm surges from the West Pacific (Webster et al. 2005). At the same time, various deltas and coastal cities also experience (often anthropogenically induced) land subsidence (Syvitski 2008).