Past, Present, And Future Dynamics Of Natural Hazards In China’s Coastal Region: Resilience Implications And Role Of Natural Habitat

Coastal areas are facing severe threats from coastal natural hazards i.e.storm surges,typhoons,and the intensity of these hazards appear to increase due to dramatic climate change.This situation exacerbates coastal vulnerabilities,and indicates increasing future risks.Therefore,it is critical to explore the present status of community resilience to cope with natural hazards.It is also of great importance to seek the more cost effective and environmental friendly tactics to mitigate risks from these natural hazards.We took typhoon activity as a most representative of disastrous hazards for the assessment of historical spatial-temporal trends and patterns in frequency and destructiveness and sea level rise to predict future vulnerabilities in terms of storm suiges under different scenarios of sea level rise and natural habitats.We also estimated the potential of coastal natural habitats to shield the populations that where and to what extent these habitats can lessen the risks for coastal communities from coastal natural hazards.We analyzed previous temporal trends and regime shifts(if any)in frequency,as well as destructiveness of landfall typhoons.The utilized best-track dataset was downloaded from Chinese Meteorological Administration(CMA)and assessments were made by using Power Dissipation Index(PDI)as an indicator of destructiveness.For spatial analysis,we used spatial statistical approach based on geospatial modelling methods in ArcGIS package.For current and future vulnerability from sea level rise induced natural hazards,we used coastal vulnerability model from Integrated Valuation of Ecosystems and Tradeoffs(InVEST)integrated with ArcGIS.To quantify the potential of natural habitats in reducing the risks from natural hazards,different sea level rise(based on IPCC sea level rise projections)by natural habitat(based on LUCC data of coastal reclamation for last 25 years)scenarios were produced.Ultimately,an overview of current resilience status was assessed based on capacity indicators of community resilience.A list of very important indicators was also formulated through partial least squares regression based on the contribution of each variable in shaping the overall community resilience score.Based on the results of typhoon activity,the coastal region of China has experienced huge variation of spatial-temporal trends and patterns in both frequency and destructiveness of typhoons.There has been a decline of landfall frequency in most of the provinces along coastal area recently.However,there was a significant increasing trend in PDIs of typhoons hotspots in different provinces(in South-eastern China,except Hainan).This province has a decreasing trend due to a northward shift of landfalling typhoons.Moreover,today,about 25%of the coastline and more than 5 million residents are located in highly vulnerable coastal areas in China.By 2100,this is expected to be doubled.The analysis of different scenarios reveals that the restoration and conservation in recently reclaimed areas are critical in reducing the vulnerability to coastal natural hazards by 45%.This also compliment the notion that natural habitats are believed to be great defense against coastal hazards such as typhoons and storm surges and there is a high confidence that resilience of coastal communities highly relies on the coastal ecological system.Based on the 25 potential indicators of community resilience to coastal natural hazards,the resilience assessment reveals that most of the coastal provinces in China lack in ecological and safety dimension of community resilience.Therefore,it is critical for Chinese government to consider the conservation and restoration of coastal natural habitats in view of their pre-disaster defense against coastal natural hazards and other associated services.