Importance of long-term earthquake, tsunami and tropical cyclone data for disaster risk reduction in Bangladesh

Abstract

Bangladesh is vulnerable to a variety of natural hazards including frequent tropical cyclones and, less commonly, earthquakes and tsunamis. The 1762 event is often cited as evidence for these latter hazard types. Remarkably, few historical data are available to help contribute to disaster risk reduction in Bangladesh. This paper addresses this gap by collating and analyzing selected histories and geographies of earthquakes, tsunamis and tropical cyclones affecting Bangladesh. It reviews and synthesizes the findings of three new catalogues consisting of 562 earthquakes (between 810BC and 2012), 135 tsunamis (between 40000BP and 2009) and 304 tropical cyclones (between 1000 and 2009) occurred in the Bay of Bengal and Bangladesh. Although Bangladesh had only been affected by a few major earthquakes and tsunamis in the distant past, the case history analysis of the 1762 earthquake and associated tsunami suggests that any future event may result in significant damage to homes, and loss of numerous lives and could cause significant liquefaction, compaction, landslides, and co-seismic subsidence. Data analysis suggests that deaths associated with tropical cyclones are declining, but economic damage and other effects are rising. Finally, this research concludes that analyses of long-term data help identify new hazard exposure and develop knowledge that can be useful to formulate new disaster risk reduction policies and rectify existing ones in Bangladesh.