EGU Journal Logos (RGB) Open Access Open Access Open Access Advances in Annales Nonlinear Processes Geosciences Geophysicae in Geophysics Open Access Open Access Nat. Hazards Earth Syst. Sci., 13, 1723–1734, 2013 Natural Hazards Natural Hazards www.nat-hazards-earth-syst-sci.net/13/1723/2013/ doi:10.5194/nhess-13-1723-2013 and Earth System and Earth System © Author(s) 2013. CC Attribution 3.0 License. Sciences Sciences Discussions Open Access Open Access Atmospheric Atmospheric Chemistry Chemistry and Physics and Physics A relative vulnerability estimation of flood disaster using data Discussions Open Access Open Access envelopment analysis in the Dongting Lake regionAtmospheric of Hunan Atmospheric Measurement Measurement C.-H. Li1,2, N. Li1,3,4, L.-C. Wu2, and A.-J. Hu5 Techniques Techniques 1 State Key Laboratory of Earth Surface Processes and Resource Ecology, Beijing Normal University, Beijing 100875, China Discussions 2 Open Access College of Science, Central South University of Forestry and Technology, Changsha 410004, China Open Access 3Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs & Ministry of Education, Beijing 100875, China Biogeosciences Biogeosciences 4Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education of China, Beijing 100875, China Discussions 5Hunan Meteorological Bureau, Changsha 410007, China Open Access Correspondence to: N. Li (ningli@bnu. edu. cn) Open Access Climate Received: 24 January 2012 – Published in Nat. Hazards Earth Syst. Sci. Discuss.: – Climate Revised: 9 December 2012 – Accepted: 15 May 2013 – Published: 4 July 2013 of the Past of the Past Discussions Abstract. The vulnerability to flood disaster is addressed ferent vulnerability level. The overall vulnerability is not the Open Access Open Access by a number of studies. It is of great importance to ana- aggregation of its components’ vulnerability. On a spatial Earth System lyze the vulnerability of different regions and various peri- scale, zones central andEarth adjacent System to Dongting Lake and/or ods to enable the government to make policies for distribut- river zones are characterized withDynamics very high vulnerability. Dynamics ing relief funds and help the regions to improve their capa- Zones with low and very low vulnerability are mainly dis- Discussions bilities against disasters, yet a recognized paradigm for such tributed in the periphery of the Dongting Lake region. On a studies seems missing. Vulnerability is defined and evaluated temporal scale, the occurrence of a vibrating flood vulnera- Open Access through either physical or economic–ecological perspectives bility trend is observed. A differentGeoscientific picture is displayed with Geoscientific Open Access depending on the field of the researcher concerned. The vul- the disaster driver risk level,Instrumentation disaster environment stability Instrumentation nerability, however, is the core of both systems as it entails level and disaster bearer sensitivityMethods level. and Methods and systematic descriptions of flood severities or disaster man- The flood relative vulnerability estimation method based agement units. The research mentioned often has a develop- on DEA is characteristic ofData good comparability,Systems which takes Data Systems ment perspective, and in this article we decompose the over- the relative efficiency of disaster system input–output into Discussions Open Access Open Access all flood system into several factors: disaster driver, disas- account, and portrays a very diverse but consistent picture Geoscientific ter environment, disaster bearer, and disaster intensity, and with varying time steps. Therefore,Geoscientific among different spatial take the interaction mechanism among all factors as an indis- and time domains, we could compare the disaster situations Model Development Model Development pensable function. The conditions of flood disaster compo- with what was reflected by the same disaster. Additionally, Discussions nents are demonstrated with disaster driver risk level, disas- the method overcomes the subjectivity of a comprehensive ter environment stability level and disaster bearer sensitivity, flood index caused by using an a priori weighting system, Open Access Open Access respectively. The flood system vulnerability is expressed as which exists in disasterHydrology vulnerability estimation and of current Hydrology and vulnerability = f (risk, stability, sensitivity). Based on the disasters. theory, data envelopment analysis method (DEA) is used to Earth System Earth System detail the relative vulnerability’s spatiotemporal variation of Sciences Sciences 1 Introduction a flood disaster system and its components in the Dongting Discussions Open Access Lake region. Open Access The study finds that although a flood disaster system’s rel- Although flood vulnerability estimation is very important for ative vulnerability is closely associated with its components’ minimizing flood damage as much as possible and making Ocean Science the better decisions onOcean sustainable Science region development, there conditions, the flood system and its components have a dif- Discussions has been no exact explanation about what vulnerability is. Open Access Published by Copernicus Publications on behalf of the European Geosciences Union. Open Access Solid Earth Solid Earth Discussions Open Access Open Access The Cryosphere The Cryosphere Discussions 1724 C.-H. Li et al. : A relative vulnerability estimation of flood disaster Since O’Keefe et al. (1976) first introduced the concept of lated structure system, paying more attention to the role of vulnerability by exploring the key role played by socioeco- the disaster bearer in creating the vulnerability. Shi (2005) nomic factors in creating a weakness in responding to, and denoted that the disaster was composed of disaster environ- recovering from the effects of extreme geophysical events in ment, disaster bearer and disaster driver, emphasizing the the context of disasters, the use of the term has varied among hazards, hazard-affected bodies are of equal importance, and disciplines and research areas over the last several decades the vulnerability could be seen as the interaction function (Liverman, 1990; Dow and Dowing, 1995; Watts and Bohle, between hazards and hazard-affected bodies under certain 1993; Cutter, 1996; Vogel, 1997). The meanings of vulner- hazard-formative environments. Klein et al. (2003) expressed ability have been integrated in three dimensions. (1) Natu- vulnerability for the natural environment as a function of ral sciences mainly focus on the physical system to define three main components: resistance, the ability to withstand vulnerability, leaving out socioeconomic characteristics of change due to a hazard; resilience, the ability to return to the the system. For example, the International Panel of Climate original state following a hazardous event and susceptibility; Change defined vulnerability as the degree of incapability to and the current physical state, without taking into account cope with the consequences of climate change and sea level temporal changes. Their definition is specifically relevant to rise. It explained the concept of vulnerability as the degree society. Klein et al. (2003) developed a scheme to explain the to which a system is susceptible to, or unable to cope with interaction between the components of vulnerability. He de- adverse effects of climate change, including climate variabil- fines vulnerability as: vulnerability = f (exposure, sensitiv- ity and extremes. Vulnerability is a function of the charac- ity, adaptive capacity). The definition demonstrates that vul- ter, magnitude and rate of climate variation to which a sys- nerability is registered not by exposure to hazards (pertur- tem is exposed, including its sensitivity and its adaptive ca- bations and stresses) alone but also resides in the sensitiv- pacity. Downing (2005) looked upon the vulnerability as the ity and resilience of the system experiencing such hazards. residual impacts of climate change after adaptation measures Van der Veen and Logtmeijer (2005) described that the vul- have been implemented. This definition includes the expo- nerability was characterized as a function of dependence, re- sure, susceptibility, and the capability of a system to recover, dundancy and susceptibility. Susceptibility is the probability and to resist hazards as a result of climate change; (2) so- and extent of flooding. Dependency is the degree to which cial science takes another point of view to explain vulnera- an activity relates to other economic activities in the rest of bility, focuses on the human’s capacity to respond to hazards the country. Redundancy is the ability of an economic activ- and to promptly recover from damages and losses. Watts and ity to respond to a disaster by deferring, using substitutes or Bohle (1993) looked to the social context of hazards and re- relocating. Redundancy is measured as the degree of central- late (social) vulnerability to coping responses of communi- ity of an economic activity in a network. The more central ties, including societal resistance and resilience to hazards. an activity is, the less it encounters possibilities to transfer They are trying to find an easier way to understand and re- production and the more vulnerable it is for flooding. Gheo- duce the concept through a better understanding of the social rghe (2005) explained vulnerability as a function of suscep- background; (3) natural and socioeconomic