Disasters and climate change

Action on disaster risk reduction can support sustainable development under climate change. 2.1 Increasing weather related losses According to data collected by Munich Re, global costs (inflation adjusted, 2006 dollars) of weather-related disasters have increased from an annual average US$8.9 billion (1977-1986) to US$45.1 billion (1997-2006). Munich Re’s data comes from their NatCatSERVICE database and includes losses from designated great natural weather catastrophes. Great natural catastrophes match the criteria that an affected region’s ability to help itself is distinctly overtaxed and hence interregional or international assistance is necessary. As subsidiary criteria serve substantial overall losses defined as exceeding 10 6 * 5% of per capita GDP (developed countries) or at least US$300 million (developing countries) and/or more than a thousand fatalities, and/or more than a hundred thousand people made homeless. This data set is generated to be homogenous since the 1970s, as it does not include smaller weather events that would be underreported earlier in the record. Annual losses in Munich Re’s global data set are highly correlated (r=0.68) with annual U.S. hurricane losses from 1970-2005 (Pielke et al., 2008). However, because of issues related to data quality, the low frequency of extreme event impacts, limited length of the time series, and various societal factors present in the disaster loss record, it is still not possible to determine the portion of the increase in damages that might be attributed to climate change brought about by greenhouse gas emissions (Höppe and Pielke, 2006). This conclusion is likely to remain unchanged in the near future (Höppe and Pielke, 2006). Inflation-adjusted data from Munich Re indicates that the average annual losses from the period 1977-1986 to the period 1997-2006 increased at a decadal rate of about 125%. Over the same period, annual growth in real GDP was smaller, and averaged 35 to 45% between decades (OECD, 2001; IMF, 2006). The larger increase in disaster losses could reflect more rapid relative growth in vulnerable locations, changes in climate events (regardless of cause), or both. Median annual losses increased between the two periods by a decadal rate of about 55%. The increase in median losses is lower than the mean because the size of the largest losses increased by a greater amount. The largest annual loss in the most recent This chapter was published as L.M. Bouwer, R.P. Crompton, E. Faust, P. Höppe, R.A. Pielke Jr. (2007). Confronting disaster losses. Science, 318, 753. Reprinted with permission from AAAS.