IPCC_Managing Risks of Extreme Events.pdf - Climate Access

Chapter 4Changes in Impacts of Climate Extremes: Human Systems and EcosystemsBox 4-4 | Extraordinary Heat Wave in Europe, Summer 2003The extraordinarily severe heat wave over large parts of the European continent in the summer of 2003 produced record-breakingtemperatures particularly during June and August (Beniston, 2004; Schär et al., 2004). Average summer (June to August) temperatureswere by up to five standard deviations above the long-term mean, implying that this was an extremely unusual event (Schär andJendritzky, 2004). Regional climate model simulations suggest the 2003 heat wave bears resemblance to summer temperatures in thelate 21st century under the A2 scenario (Beniston, 2004).Electricity demand increased with the high heat levels. Additionally, drought conditions created stress on health, water supplies, foodstorage, and energy systems; for example, reduced river flows reduced the cooling efficiency of thermal power plants (conventional andnuclear), and six power plants were shut down completely (Létard et al., 2004). Many major rivers (e.g., the Po, Rhine, Loire, and Danube)were at record low levels, resulting in disruption of inland navigation and irrigation, as well as power plant cooling (Beniston and Díaz,2004; Zebisch et al., 2005). In France, electricity became scarce, construction productivity fell, and the cold storage systems of approximately20 to 30% of all food-related establishments were found to be inadequate (Létard et al., 2004). The (uninsured) economic losses for theagriculture sector in the European Union were estimated at € 13 billion (Sénat, 2004). A record drop in crop yield of 36% occurred inItaly for maize grown in the Po valley, where extremely high temperatures prevailed (Ciais et al., 2005). The hot and dry conditions led tomany very large wildfires. Glacier melting in the Alps prevented even lower river flows in the Danube and Rhine (Fink et al., 2004).Health and health service-related impacts of the heat wave were dramatic, with excess deaths of about 35,000 (Kosatsky, 2005). Elderlypeople were among those most affected (WHO, 2003; Borrell et al., 2006; Kovats and Ebi, 2006), but deaths were also associated withhousing and social conditions, for example, being socially isolated or living on the top floor (Vandentorren et al., 2006). The high mortalityduring the 2003 heat wave marked an inflexion point in public awareness of the dangers of high temperatures, conducive to increasingthe preventive measures set up by health institutions and authorities (Koppe et al., 2004; Pascal et al., 2006).During the July 2006 heat wave, about 2,000 excess deaths occurred in France (Rey et al., 2007). The excess mortality during the 2006heat wave was markedly lower than that predicted by Fouillet et al. (2008) based on the quantitative association between temperatureand mortality observed during 1975-2003. Fouillet et al. (2008) interpreted this mortality reduction (~4,400 deaths) as a decrease in thepopulation’s vulnerability to heat, together with increased awareness of the risk related to extreme temperatures, preventive measures,and the warning system established after the 2003 heat wave.B1 emission scenarios. The Netherlands is an example of a country thatis highly susceptible to both sea level rise and coastal flooding, withdamage costs relative to GDP of up to 0.3% of GDP under the A2scenario (Hinkel et al., 2010). By 2100, adaptation can reduce thenumber of people flooded by two orders of magnitude and the totaldamage costs by a factor of seven to nine (Hinkel et al., 2010).4.4.5.5. Gale WindsStorms have been one of the most important climate hazards for theinsurance industry in Europe (Munich Re NatCatSERVICE data cited inEEA, 2008). In the most severe extratropical windstorm month,December 1999, when three events struck Europe (Anatol – December 3,Denmark; Lothar – December 26, France, Germany, and Switzerland;and Martin – December 28, France, Spain, and Italy), insured damagewas in excess of US$ 12 billion (Schwierz et al., 2010). Typical economiclosses were generated by gale winds via effects on electrical distributionsystems, transportation, and communication lines; by damage tovulnerable elements of buildings (e.g., lightweight roofs); and by treesfalling on houses. Some researchers have found no contribution fromclimate change to trends in the economic losses from floods in Europesince the 1970s (Barredo, 2009). Some studies have found evidence ofincreasing damages to forests in Sweden and Switzerland (Nilsson etal., 2004; Usbeck et al., 2010). Still other studies assert that increases inforest disturbances in Europe are mostly due to changes in forestmanagement (e.g., Schelhaas et al., 2003).There is medium confidence in projected poleward shifts of mid-latitudestorm tracks but low confidence in detailed regional projections (seeSection 3.4.5). According to a study by Swiss Re (2009), if by the end ofthis century once-in-a-millennium storm surge events strike northernEurope every 30 years, this could potentially result in a disproportionateincrease in annual expected losses from a current € 0.6 to 2.6 billion byend of the century. Similar results are obtained from global and regionalclimate models run under the IPCC SRES A1B emission scenario (Donatet al., 2010). Adaptation to the changing wind climate may reduce byhalf the estimated losses (Leckebusch et al., 2007; Donat et al., 2010),indicating that adaptation through adequate sea defenses and themanagement of residual risk is beneficial.257