Deterministic Disaster Exceeding the Coping Range

Elevated mortality rates during naturally occurring summer heat waves have received considerable attention since Ellis et al. (1975). A common observation in subsequent studies is that absence of seasonal and short term acclimatization is a major determinant of increased mortality (Kilbourne 1989; Kalkstein 1991, 1997; Kalkstein and Davis 1989; Kalkstein and Smoyer 1993; Smoyer 1998), and that especially age and poverty are significant contributory factors (Kilbourne 1989; Smoyer 1996).

The definition of heat wave and any other atmospheric hazard is therefore a matter of both the intensity of the parameter, which can be quantified by complex heat budget indices such as Klima-Michel (Jendritzky and Nubler 1981), STEBIDEX (de Freitas 1985) and PET (Hoppe 1999) models, and population risk characteristics. As found by Karen Smoyer (1998), however, when related to mortality data, the best index utilizes adaptation parameters: her best predictors of heat deaths in St Louis were duration of heat waves and time sequence within the hot season.

During the decades around the turn of the twenty-first century, the global community has been struck by severe weather, including exceptional summer heat waves and pronounced death rate increase at the time. The European summer of especially 2003 was abnormally warm. In Paris maximum temperatures rose to above 35°C for 10 days until the 13th of August and for 4 days were above 38°C. Given that in urban areas heat islands develop, in the larger cities the levels of heat stress would have been more elevated in particular locations. For example, satellite imagery showed a systematic 4°C difference between parks, industrial and residential areas of Paris (Doussett 2007).

In much of Western Europe, emergency services, both fire departments and hospitals, showed abrupt increases in the number of interventions. Excess deaths for Europe in the first 2 weeks of August 2003 were around 35,000 (New Scientist 2003). Fouillet et al. (2006) examined the 15,000 causes of death in France using the International Classification of Diseases (ICD10) and an additional category for deaths reported to be directly related to the heat wave by the physician, i.e. dehydration, hyperthermia and heatstroke. The biggest cause of excess death was directly heat related: heatstroke, hyperthermia and dehydration + 3,306 deaths (a 20-fold overall increase in the number of deaths, and an even greater increase in certain age-group categories), circulatory system diseases + 3,004 deaths, ill-defined morbid conditions + 1,741 deaths, respiratory system diseases + 1,365 deaths and nervous system diseases + 1,001 deaths. By far the greatest increases in mortality were indeed in the older age groups. Fouillet et al. (2006) extrapolated " no segment of the population may be considered protected from the risks associated with heat waves".

Bouchama et al. (2007) analyzed details in reported heat stress cases both in Europe and USA as related to factors contributing to excess deaths as listed in web Medline, WHO and EU Centre for Environment and Health, and national disease control center databases for the period from January 1966 to March 2006. Analysis of 1,065 cases through "case-control" or "cohort studies" of odds ratios (ORs) established statistically significant associations, both beneficial and detrimental.

The beneficial were the mitigation by technological devices. The availability of working air conditioning (P < 0.01) was the strongest protective factor, followed by access to an air conditioned place for some hours (P < 0.001). There also seemed to be a trend that showed taking extra showers or baths and use of a fan during a heat wave reduced the risk of dying. Of benefit was also participation in social activities (P < 0.01).

The detrimental associations were in the area of health. This included poor general health: being confined to bed (P < 0.001), unable to adequately care for self (P < 0.001) or to leave home daily (P < 0.001), or having a preexisting cardiovascular (P< 0.01), pulmonary (P < 0.001), or psychiatric (P < 0.01) condition. In addition in the USA, but not in France, living alone greatly increased the risk of dying (P < 0.001) during a heat wave.

The excess 2003 French death increases are graphically presented in Fig. 11.4, which also shows average daily maximum (Tmax) and minimum (Tmin) temperatures, estimated thermal neutrality (T^) and accumulated heat stress values (AHDD) for the period. The latter were calculated to allow for psycho-physiological acclimatization as estimated by T^ and for Smoyer's (1998) duration*time factors by

Coping Psychologie France

Day Irom July 1st to September 30th, 2003

Fig. 11.4 Excess Deaths in France During the Heat Wave of 2003. (Based on Fouillet et al 2006) Average daily maximum (T ) and minimum (T . ) temperatures recorded in Paris, and estimated accumulated daily heat stress in degrees calculated by summation of maximum temperatures in excess of thermal neutrality for the preceding two weeks, which becomes the base value for this accumulated heat stress "degree day" AHDD=Z7(Tmax - Ty) / 7

Day Irom July 1st to September 30th, 2003

Fig. 11.4 Excess Deaths in France During the Heat Wave of 2003. (Based on Fouillet et al 2006) Average daily maximum (T ) and minimum (T . ) temperatures recorded in Paris, and estimated accumulated daily heat stress in degrees calculated by summation of maximum temperatures in excess of thermal neutrality for the preceding two weeks, which becomes the base value for this accumulated heat stress "degree day" AHDD=Z7(Tmax - Ty) / 7

summation of daily mean maximum temperatures in excess of variable thermal neutrality calculated for the preceding 2 weeks, which become the base values for this accumulated heat stress "degree day" method:

Three weeks of July, August and September showed mean daily AHDD > 4. Those week ending on 17/7 AHDD = 8, 7/8 AHDD = 14 and 14/8 AHDD = 13, while the monthly accumulated totals for July were 134, August 254 and September 30. The correlation between excess deaths and AHDD values as shown in Fig. 11.4 is high, but perhaps surprisingly, these daily averages and Tmax - Ty seem to fall well within the estimated warm coping range of 12-17°C (Fig. 11.3).

This particular coping range, however, was estimated for healthy and relatively young people, while the excess European death rates showed victims to be the elderly, the ill and the less well off with decreased mobility. It is likely that the victims were poorly acclimatized, and their coping ranges would have been reduced by perhaps 4°C. Moreover, amongst them, many would have been homeless, or in poorly ventilated buildings that might not have been adequately cooled down during night time. Without such cooling down, and without the benefits of day time insulation, the CR would have been reduced by a further 5-10°C. In other words, it is probable that the coping rages of the victims were no more than the sum of CRV + CRpa that is no more than 2-3°C.

On the one hand, the immediate cause of death was at the first order biological adaptation level due to reduced coping ranges, while on the other, the Bouchama et al. (2007) analysis points to life saving measures within second order technology, as controlled within third social systems level. The Fouillet et al. (2006) extrapolation that no segment of the population may be considered protected from the risks associated with heat waves may have been somewhat hasty: the victims were not those cocooned by the higher order adaptation mechanisms.

Previous American experience had found that mitigation of heat wave stress carried implications for policies of social intervention. In Chicago, elevated temperatures had led to some 700 excess death rates in 1995. In a press interview Eric Klinenberg (2002) is reported: "Yes, the weather was extreme. But the deep sources of the tragedy were the everyday disasters that the city tolerates, takes for granted, or has officially forgotten "In 1999, when Chicago experienced another severe heat wave, the city issued strongly worded warnings and press releases to the media, opened cooling centers and provided free bus transportation to them, phoned elderly residents, and sent police officers and city workers door-to-door to check up on seniors who lived alone. That aggressive response drastically reduced the death toll of the 1999 heat wave: 110 residents died, a fraction of the 1995 level but still catastrophic". The Chicago applications are in tune with the findings of Bouchama et al. (2007) who agreed that "the notion that withdrawing this distinct population at risk from heat, even for a short time, is the cornerstone of any public health response during a severe heat wave."

Clearly, as in the case of Chicago, simple and temporary intervention at higher levels could be successful, but further modeling might suggest more permanent solutions within issues of social equality. The tragedy of the European 2003 episode is exacerbated by the fact that effective models for proactive third order adaptations to heat waves were already available through appropriate warning forecasts as pioneered by Brezowsky (1960) and their translation by Larry Kalkstein (1997), as in the Philadelfia system, which was designed for intervention by the Department of Public Health through improving communications, and especially telephone hot-lines, between the public and agencies such as public utilities, aged care centers, and actions by proactive, reactive and buddy teams of professionals and volunteers.

As a postscript to the 2003 heat wave disaster, Fouillet et al. (2008) have analyzed the subsequent 2006 episode in France. No data are given on social conditions, but in terms of the earlier episode, death increases are a half of those expected. Fouillet et al. (2008) conclude that this can be "interpreted as a decrease in the population's vulnerability to heat, together with, since 2003, increased awareness of the risk related to extreme temperatures, preventive measures and the set-up of the warning system". Leaving aside the question whether that particular French population has actually become less vulnerable and more aware, or had been culled in size by the 2003 episode, heat wave warning systems have been now either activated or proposed for a large number of urban areas, including all 17 major cities in France (Kovats and Ebi 2006). Perhaps the most encouraging development is that warnings can be based simply on average daily temperatures (Nicholls et al. 2008), which can be reliably forecast for most locations 3-5 and more days in advance.

Finally, in the light of such observations, should the lens of modern thermoregu-latory adaptation be enlarged back again and applied to tropical settlement, what were once perceived as negative characteristics within colonists and indigenous peoples, may now be interpreted as appropriate adaptive responses within given conditions. Tropical locations, as for example in lowland India, the Philippines, and Queensland Australia, where winter temperatures are often warmer than those in Britain in summer, were not benevolent to Europeans determined to maintain the lifestyles, schedules, fashions and customs evolved within much cooler climates (Auliciems and Deaves 1988). Woodruff and Huntington were not mistaken in observing that the effects of the elevation of work metabolism, whilst wearing heavy Victorian clothing either outdoors or in poorly designed uninsulated and unshaded buildings of that period, could indeed do no other than promote severe discomfort, improper behavior or ill health. As early on recognized by Raphael Cilento (1925); Thomas Griffith Taylor (1959) and Sargent (1963), successful settlement requires profound adaptive changes in custom and technology.

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