In the field of disaster risk analysis various approaches using indicators for vulnerability assessment can be found (Cardona, 2004, Cutter et al 2003, Dilley et al., 2005, Peduzzi, 2006, Balica et al, 2009).
All these approaches aim at assessing risk and vulnerability quantitatively by means of indicators to compare different regions or communities (Birkmann, 2007, Schmidtlein et al., 2008). In the context of vulnerability assessment, indicators embody an operational representation of a characteristic or a quality of a system able to provide information regarding the susceptibility, coping capacity, and resilience of a system to an impact of a disaster (Birkmann, 2006). The vulnerability of a system is in general determined by different factors. Therefore, the vulnerability cannot be captured by one single indicator. Instead multi-dimensional concepts, such as composite indices, are needed to assess the vulnerability of such a system. Composite indices are formed when individual indicators are compiled to a single index based on an underlying theoretical vulnerability framework (model) (Nardo et al.
, 2005). As described above, in risk perceptions the understanding of vulnerability is very broad and current literature encompasses many different definitions, concepts, and methods to systemize vulnerability (Birkmann, 2007, Cutter et al., 2003). Villagran de Leon (2006) defines vulnerability as the predisposition of an element or a system to be affected or susceptible to damage. Due to the complex phenomenon of vulnerability, the measurement of vulnerability (and especially its social and economic component) can be challenging (Brooks et al., 2005).
In the field of natural disaster risk assessment one methodology to evaluate the vulnerability is the use of indicator approaches (Adger, 2005, Cardona, 2006, Dilley et al., 2005, Pelling, 2004, Perduzzi, 2006). In general, the data of most interest from the point of view of vulnerability assessment are those relating to mortality and the numbers of people adversely affected by climate-related events.
While economic damage is also an important indicator of the severity of the impacts of climate-related disasters, data relating to the cost of disasters are relatively sparse and are also difficult to estimate.