GAR 2013 Main Report

(Source: UNISDR, adapted from CIMNE et al., 2013b)

Figure 4.7 Hybrid loss exceedance curve for Guatemala

4.3

Hidden risk layers

A newly applied methodology to evaluate direct loss and damage from extensive disaster events allows extensive risk to be expressed as a loss exceedance curve. This enables countries to develop a more complete analysis of risk and of their contingent liabilities associated with disasters.

Extensive risks are rarely recorded, and therefore not taken into account in national risk assessments, which usually only focus on intensive risks. GAR11 (UNISDR, 2011

UNISDR. 2011.,Global Assessment Report on Disaster Risk Reduction: Revealing Risk, Redefining Development., United Nations International Strategy for Disaster Reduction., Geneva,Switzerland: UNISDR.. .

) presented a new hybrid loss exceedance curve as a way of combining and measuring both extensive and intensive risks at the country level. Additional hybrid curves have now been developed for eight Latin American countries.ⁱⁱⁱ

Figure 4.7 shows the hybrid curve for Guatemala. The empirical curve, based on historical loss data,

provides information on largely extensive risks with return periods of up to approximately 30 years but does not capture intensive risks with longer return periods. Similarly, the analytical curve estimated using a probabilistic risk model does not capture much of the extensive risk with shorter return periods. The hybrid curve captures both.

Figure 4.8, based on hybrid loss exceedance curves for ten Latin American countries (CIMNE et al., 2013b ; GAR 13 paper

ERN-AL, 2011

ERN-AL (Consortium Evaluación de Riesgos Naturales – America Latina). 2011.,Probabilistic modelling of disaster risk at global level: development of a methodology and implementation of case studies. Phase 1A: Colombia, Mexico and Nepal., Background Paper prepared for the 2011 Global Assessment Report on Disaster Risk Reduction., Geneva,Switzerland.
Click here to view this GAR paper.

), highlights the annual average loss (AAL) that would be expected from all disasters, intensive and extensive, both in absolute terms and expressed as a percentage of gross fixed capital formation (GFCF). Although Mexico has the highest probable AAL in absolute terms, in relative terms, Honduras stands to lose more than 12 percent of its gross fixed capital formation every year owing to direct disaster losses.

This kind of information is valuable to inform investments in disaster risk reduction. Often, the costs of