Papers on 2003 heat wave in Europe

This is a list of papers on 2003 heat wave in Europe. The list is not complete, and will most likely be updated in future in order to make it more thorough and more representative.

Heat-related mortality in the Florentine area (Italy) before and after the exceptional 2003 heat wave in Europe: an improved public health response? – Morabito et al. (2012) “High ambient temperatures have been associated with increased mortality across the world. Several studies suggest that timely preventive measures may reduce heat-related excess mortality. The main aim of this study was to detect the temporal modification of heat-related mortality, in older adults (aged 65–74) and in elderly ≥75 years old, in the Florentine area by comparing previous (1999–2002) and subsequent (2004–2007) periods to the summer of 2003, when a regional Heat-Health Warning System (HHWS) was set up. Mortality data from 1999 to 2007 (May–September) were provided by the Mortality Registry of the Tuscany Region (n = 21,092). Weather data were used to assess daily apparent temperatures (AT). Case-crossover time-stratified designs and constrained segmented distributed lag models were applied. No significant heat-related mortality odds ratio (OR) variations were observed among the sub-periods. Nevertheless, a general OR decrease dating from 1999–2002 (OR 1.23; lack of HHWS) to 2004–2005 (OR 1.21; experimental HHWS running only for Florence) and to 2006–2007 (OR 1.12; official HHWS extended to the whole Florentine area) was observed when the maximum AT was considered. This modification was only evident in subjects ≥75 years old. The heat effect was higher and sustained for more days (until lag 9) during the period 1999–2002 than 2004–2007. The decrease of the excessive heat effect on mortality between periods with the absence and existence of a HHWS is also probably due to the mitigation of preventive measures and the implementation of a HHWS with specific interventions for safeguarding the health of the “frail elderly”.” Marco Morabito, Francesco Profili, Alfonso Crisci, Paolo Francesconi, Gian Franco Gensini, Simone Orlandini, International Journal of Biometeorology, September 2012, Volume 56, Issue 5, pp 801-810, DOI: 10.1007/s00484-011-0481-y.

Influence of sea surface temperature on the European heat wave of 2003 summer. Part I: an observational study – Feudale & Shukla (2011) “The heat wave affecting Europe during summer of 2003 is analyzed in detail with observational and reanalysis data. Surface, middle and upper troposphere analysis reveal particular circulation patterns related to an atmospheric blocking condition. In general seasonal anomalies, like this intense heat wave, are strongly related to boundary conditions. Composites and empirical orthogonal functions analysis provide evidence for an organized structure in the sea surface temperature (SST) anomaly field: high SSTs in the Mediterranean basin, the North Sea and further north toward the Arctic Circle were observed mainly in the months of June and August. The outcome of this analysis on observational data shows the SST as one of the possible factors in enhancing the heat wave in the European area.” Laura Feudale, Jagadish Shukla, Climate Dynamics, May 2011, Volume 36, Issue 9-10, pp 1691-1703, DOI: 10.1007/s00382-010-0788-0. [Full text]

Influence of sea surface temperature on the European heat wave of 2003 summer. Part II: a modeling study – Feudale & Shukla (2011) “The Center for Ocean–Land–Atmosphere Studies Atmospheric General Circulation Model is used to investigate the role of global boundary conditions of sea surface temperature (SST) in the establishment and maintenance of the European heat wave of 2003 summer. It is found that the global SST anomalies can explain many major features of the European heat wave during the summer of 2003. A further experiment has investigated the role of SST outside the Mediterranean area. This supplements the results of a previous study where the role of warm Mediterranean SST was analyzed. The results suggest that the SST anomalies had an additional effect of reducing the baroclinicity in the European area reinforcing the blocking circulation and helping to create ideal conditions for the establishment of the heat wave.” Laura Feudale, Jagadish Shukla, Climate Dynamics, May 2011, Volume 36, Issue 9-10, pp 1705-1715, DOI: 10.1007/s00382-010-0789-z.

Impact of aerosol direct radiative forcing on the radiative budget, surface heat fluxes, and atmospheric dynamics during the heat wave of summer 2003 over western Europe: A modeling study – Péré et al. (2011) “In this work, an off-line coupling between the chemistry-transport model CHIMERE (associated with an aerosol optical module) and the meteorological model Weather Research and Forecasting (WRF) is used to study (1) the direct radiative forcing of pollution aerosols during the heat wave of summer 2003 over western Europe and (2) the possible feedbacks of this direct radiative forcing on the surface-atmosphere system. Simulations performed for the period 7–15 August 2003 reveal a significant decrease of daily mean solar radiation reaching the surface (ΔF_BOA = −(10–30) W/m²) because of back scattering at the top of the atmosphere (ΔF_TOA = −(1–12) W/m²) and also absorption of solar radiation by polluted particles (ΔF_atm = + (5–23) W/m²). During daytime, the aerosol surface dimming induces a mean reduction of both sensible (16 W/m²) and latent (21 W/m²) heat fluxes emitted by the terrestrial surface, resulting in a radiative cooling of the air near the surface (up to 2.9 K/d at noon). Simultaneously, the absorption of solar energy by aerosols causes an atmospheric radiative heating within the planetary boundary layer reaching 1.20 K/d at noon. As a consequence, the direct radiative effect of aerosols is shown to reduce both the planetary boundary layer height (up to 30%) and the horizontal wind speed (up to 6%); that may have contributed to favor the particulate pollution during the heat wave of summer 2003.” J. C. Péré, M. Mallet, V. Pont, B. Bessagnet, Journal of Geophysical Research: Atmospheres (1984–2012), Volume 116, Issue D23, December 2011, DOI: 10.1029/2011JD016240.

A Review of the European Summer Heat Wave of 2003 – García-Herrera et al. (2010) “This paper reviews the European summer heat wave of 2003, with special emphasis on the first half of August 2003, jointly with its significant societal and environmental impact across Western and Central Europe. We show the pattern of record-breaking temperature anomalies, discuss it in the context of the past, and address the role of the main contributing factors responsible for the occurrence and persistence of this event: blocking episodes, soil moisture deficit, and sea surface temperatures. We show that the anticyclonic pattern corresponds more to an anomalous northern displacement of the North Atlantic subtropical high than a canonical blocking structure, and that soil moisture deficit was a key factor to reach unprecedented temperature anomalies. There are indications that the anomalous Mediterranean Sea surface temperatures (SSTs) have contributed to the heat wave of 2003, whereas the role of SST anomalies in other oceanic regions is still under debate. There are methodological limitations to evaluate excess mortality due to excessive temperatures; however, the different studies available in the literature allow us to estimate that around 40,000 deaths were registered in Europe during the heat wave, mostly elderly persons. Despite previous efforts undertaken by a few cities to implement warning systems, this dramatic episode has highlighted the widespread un-preparedness of most civil and health authorities to cope with such large events. Therefore, the implementation of early warning systems in most European cities to mitigate the impact of extreme heat is the main consequence to diminish the impact of future similar events. In addition to mortality (by far the most dramatic impact), we have also analyzed the record-breaking forest fires in Portugal and the evidence of other relevant impacts, including agriculture and air pollution.” R. García-Herrera, J. Díaz, R. M. Trigo, J. Luterbacher & E. M. Fischer, Critical Reviews in Environmental Science and Technology, Volume 40, Issue 4, 2010, DOI:10.1080/10643380802238137.

Increase in out-of-hospital cardiac arrest attended by the medical mobile intensive care units, but not myocardial infarction, during the 2003 heat wave in Paris, France – Empana et al. (2009) “Objectives: To address the association between the 2003 heat wave in Paris (France) and the occurrence of out-of-hospital cardiac arrest. Design: An analysis of the interventions of the medical mobile intensive care units of the City of Paris for out-of-hospital cardiac arrest and prehospital myocardial infarctions, which were routinely and prospectively computerized from January 1, 2000, to December 31, 2005. Setting: City of Paris, France. Patients: Participants were consecutive victims of witnessed out-of-hospital cardiac arrest due to heart disease and of ST-segment elevation myocardial infarction (STEMI) aged ≥18 yrs, who were attended by the medical mobile intensive care units (MICUs) of the City of Paris from January 1, 2000, to December 31, 2005. Interventions: None. Measurements and Main Results: The numbers of out-of-hospital cardiac arrests and of STEMIs during the 2003 heat wave period (August 1 to August 14) were compared (Poisson regression analysis) with the respective average numbers during the same period in reference years 2000–2002 and 2004–2005 when there was no heat wave. Mean ages of the 3049 patients experiencing out-of-hospital cardiac arrest and the 2767 patients experiencing STEMI attended by the MICUs during the study period were 64.3 ± 18.0 and 65.2 ± 15.4, respectively, and two thirds were males. During the heat wave period, the number of out-of-hospital cardiac arrests (n = 40) increased 2.5-fold compared with the reference periods (n = 81 for 5 yrs; p < .001); this corresponded to an estimated relative rates of out-of-hospital cardiac arrests of 2.34 (95% confidence interval, 1.60–3.41), after adjustment for age and for gender. This increase was observed in both genders (p for interaction with gender = .48) but only in those who were aged ≥60 yrs (p for interaction with age = .005). No variation was found for myocardial infarctions during heat wave. Conclusions: These data suggest that a heat wave may be associated with an increased risk of sudden cardiac death in the population.” Empana, Jean-Philippe MD, PhD; Sauval, Patrick MD; Ducimetiere, Pierre PhD†; Tafflet, Muriel MPH; Carli, Pierre MD; Jouven, Xavier MD, PhD, Critical Care Medicine: December 2009 – Volume 37 – Issue 12 – pp 3079-3084, doi: 10.1097/CCM.0b013e3181b0868f.

Air pollution during the 2003 European heat wave as seen by MOZAIC airliners – Tressol et al. (2008) “This study presents an analysis of both MOZAIC profiles above Frankfurt and Lagrangian dispersion model simulations for the 2003 European heat wave. The comparison of MOZAIC measurements in summer 2003 with the 11-year MOZAIC climatology reflects strong temperature anomalies (exceeding 4°C) throughout the lower troposphere. Higher positive anomalies of temperature and negative anomalies of both wind speed and relative humidity are found for the period defined here as the heat wave (2–14 August 2003), compared to the periods before (16–31 July 2003) and after (16–31 August 2003) the heat wave. In addition, Lagrangian model simulations in backward mode indicate the suppressed long-range transport in the mid- to lower troposphere and the enhanced southern origin of air masses for all tropospheric levels during the heat wave. Ozone and carbon monoxide also present strong anomalies (both ~+40 ppbv) during the heat wave, with a maximum vertical extension reaching 6 km altitude around 11 August 2003. Pollution in the planetary boundary layer (PBL) is enhanced during the day, with ozone mixing ratios two times higher than climatological values. This is due to a combination of factors, such as high temperature and radiation, stagnation of air masses and weak dry deposition, which favour the accumulation of ozone precursors and the build-up of ozone. A negligible role of a stratospheric-origin ozone tracer has been found for the lower troposphere in this study. From 29 July to 15 August 2003 forest fires burnt around 0.3×10⁶ ha in Portugal and added to atmospheric pollution in Europe. Layers with enhanced CO and NO_y mixing ratios, advected from Portugal, were crossed by the MOZAIC aircraft in the free troposphere over Frankfurt. A series of forward and backward Lagrangian model simulations have been performed to investigate the origin of anomalies during the whole heat wave. European anthropogenic emissions present the strongest contribution to the measured CO levels in the lower troposphere (near 30%). This source is followed by Portuguese forest fires which affect the lower troposphere after 6 August 2003 and even the PBL around 10 August 2003. The averaged biomass burning contribution reaches 35% during the affected period. Anthropogenic CO of North American origin only marginally influences CO levels over Europe during that period.” Tressol, M., Ordonez, C., Zbinden, R., Brioude, J., Thouret, V., Mari, C., Nedelec, P., Cammas, J.-P., Smit, H., Patz, H.-W., and Volz-Thomas, A.: Air pollution during the 2003 European heat wave as seen by MOZAIC airliners, Atmos. Chem. Phys., 8, 2133-2150, doi:10.5194/acp-8-2133-2008, 2008. [Full text]

General and specific mortality among the elderly during the 2003 heat wave in Genoa (Italy) – Conti et al. (2007) “The effects of heat waves on health can be serious for elderly persons, especially those in urban areas. We investigated in-depth the mortality excess during the 2003 heat wave among elderly persons (>74 years) in the City of Genoa (Italy). The excess in general mortality was calculated for the period July 16–August 31, as the ratio of observed to expected deaths. To evaluate “harvesting”, we compared observed and expected mortality in the period September 2003–April 2004. We also studied the relationship between mortality and climatic conditions considering daily maximum temperature and Humidex discomfort degrees, as well as “lag-time”. For cause-specific mortality, we considered all pathologies reported on the death certificate. The excess in general mortality was significant and was greatest in the first half of August. During Summer 2003, in Genoa the climatic conditions (described in terms of maximum temperature and Humidex Index) were extremely hot; regarding lag-time, the greatest correlation between the number of observed deaths and the maximum temperature values was observed for the three preceding days (ρ=0.568; significance level <0.01). The prominent causes of death, for which an excess was observed, were cerebrovascular diseases, severe respiratory diseases, severe renal diseases, dementia; moreover, certain pathologic conditions and symptoms, usually not lethal, were also frequent causes of death (e.g., hypovolemia, hyperpyrexia, decubitus ulcers and immobilization syndrome). The results of this study confirm the relationship between the heat waves and death among elderly, stressing that, because of their poorer physical health and the prevalence of cognitive disturbances that hinder risk perception, it is necessary to properly care for them during heat waves.” Susanna Conti, Maria Masocco, Paola Meli, Giada Minelli, Ernesto Palummeri, Renata Solimini, Virgilia Toccaceli, Monica Vichi, Environmental Research, Volume 103, Issue 2, February 2007, Pages 267–274, http://dx.doi.org/10.1016/j.envres.2006.06.003.

Excess mortality related to the August 2003 heat wave in France – Fouillet et al. (2006) “Objectives: From August 1st to 20th, 2003, the mean maximum temperature in France exceeded the seasonal norm by 11–12°C on nine consecutive days. A major increase in mortality was then observed, which main epidemiological features are described herein. Methods: The number of deaths observed from August to November 2003 in France was compared to those expected on the basis of the mortality rates observed from 2000 to 2002 and the 2003 population estimates. Results: From August 1st to 20th, 2003, 15,000 excess deaths were observed. From 35 years age, the excess mortality was marked and increased with age. It was 15% higher in women than in men of comparable age as of age 45 years. Excess mortality at home and in retirement institutions was greater than that in hospitals. The mortality of widowed, single and divorced subjects was greater than that of married people. Deaths directly related to heat, heatstroke, hyperthermia and dehydration increased massively. Cardiovascular diseases, ill-defined morbid disorders, respiratory diseases and nervous system diseases also markedly contributed to the excess mortality. The geographic variations in mortality showed a clear age-dependent relationship with the number of very hot days. No harvesting effect was observed. Conclusions: Heat waves must be considered as a threat to European populations living in climates that are currently temperate. While the elderly and people living alone are particularly vulnerable to heat waves, no segment of the population may be considered protected from the risks associated with heat waves.” A. Fouillet, G. Rey, F. Laurent, G. Pavillon, S. Bellec, C. Guihenneuc-Jouyaux, J. Clavel, E. Jougla and Denis Hémon, International Archives of Occupational and Environmental Health, Volume 80, Number 1, 16-24, DOI: 10.1007/s00420-006-0089-4. [Full text]

The 2003 Heat Wave in France: Dangerous Climate Change Here and Now – Poumadère et al. (2005) “In an analysis of the French episode of heat wave in 2003, this article highlights how heat wave dangers result from the intricate association of natural and social factors. Unusually high temperatures, as well as socioeconomic vulnerability, along with social attenuation of hazards, in a general context where the anthropogenic contribution to climate change is becoming more plausible, led to an excess of 14,947 deaths in France, between August 4 and 18, 2003. The greatest increase in mortality was due to causes directly attributable to heat: dehydration, hyperthermia, heat stroke. In addition to age and gender, combinatorial factors included preexisting disease, medication, urban residence, isolation, poverty, and, probably, air pollution. Although diversely impacted or reported, many parts of Europe suffered human and other losses, such as farming and forestry through drought and fires. Summer 2003 was the hottest in Europe since 1500, very likely due in part to anthropogenic climate change. The French experience confirms research establishing that heat waves are a major mortal risk, number one among so-called natural hazards in postindustrial societies. Yet France had no policy in place, as if dangerous climate were restricted to a distant or uncertain future of climate change, or to preindustrial countries. We analyze the heat wave’s profile as a strongly attenuated risk in the French context, as well as the causes and the effects of its sudden shift into amplification. Research and preparedness needs are highlighted.” Marc Poumadère, Claire Mays, Sophie Le Mer, Russell Blong, Risk Analysis
Volume 25, Issue 6, pages 1483–1494, December 2005, DOI: 10.1111/j.1539-6924.2005.00694.x. [Full text]

The impact of the summer 2003 heat waves on mortality in four Italian cities – Michelozzi et al. (2005) “This study evaluates the impact of the 2003 heat wave on cause-specific mortality and the role of demographic characteristics and socioeconomic conditions that may have increased the risk of mortality in four Italian cities: Bologna, Milan, Rome and Turin. Daily mortality counts, for the resident population by age, sex and cause of death were considered. Daily excess mortality was calculated as the difference between the number of deaths observed and the smoothed average. The impact of heat on health is measured in terms of maximum apparent temperature. The greatest excess in mortality was observed in the north west of Italy (Turin, +23% and Milan, +23%). The old (75-84 years) and the very old (85+ years) were the age groups most affected, and when stratifying by sex, the increase in mortality seemed to be greater among females. The greatest excess in mortality was registered in those with low socioeconomic status in Rome (+17.8%) and in those with lower education levels in Turin (+43%). The analysis of cause-specific mortality not only confirms results from previous studies of an increase in heat-related mortality by respiratory and cardiovascular diseases, but also shows a significant excess in mortality for diseases of the central nervous system and for metabolic/endocrine disorders. Results from 2003 highlight the necessity of targeting future prevention programmes at the susceptible sub-groups identified. The introduction of warning systems alongside efficient preventive plans and the monitoring of mortality during heat waves may represent a valid tool for the reduction of heat-related deaths.” Michelozzi P, de Donato F, Bisanti L, Russo A, Cadum E, DeMaria M, D’Ovidio M, Costa G, Perucci CA, Euro Surveillance : Bulletin Europeen sur les Maladies Transmissibles = European Communicable Disease, Bulletin [2005, 10(7):161-5].

Summary of the mortality impact assessment of the 2003 heat wave in France – Pirard et al. (2005) “France experienced a record-breaking heat wave between 2 and 15 August 2003. All the French regions were affected by this heat wave, which resulted in an excess of 14 800 deaths between 1 and 20 August. The increase in the number of excess deaths followed the same pattern as the increase in temperatures. No deviance from the normal death rate was observed in the month of August during the last third of the month, nor during the following three months. There was a clear discrepancy in the impact of the heat wave from city to city. If the effect of duration of consecutive days with high minimal temperatures and deviance with the seasonal normal temperature was patent, this could not explain all of the observed variability of the death incidence. The victims were mainly elderly women older than 75 years. In terms of relative risk and contribution to the global toll, deaths linked to heat were the most important. Based on these results, the French government developed a Heat Health Watch Warning System and set up a preventive action plan for each region in 2004.” Pirard P, Vandentorren S, Pascal M, Laaidi K, Le Tertre A, Cassadou S, Ledrans M, Euro Surveillance : Bulletin Europeen sur les Maladies Transmissibles = European Communicable Disease Bulletin [2005, 10(7):153-6].

Epidemiologic study of mortality during the Summer 2003 heat wave in Italy – Conti et al. (2005) “Introduction: It is widely recognized that extreme climatic conditions during summer months may constitute a major public health threat. Owing to what is called the “urban heat island effect,” as well as to the consequences of heat waves on health, individuals living in cities have an elevated risk of death when temperature and humidity are high compared to those living in suburban and rural areas. Studies on heat wave-related mortality have further demonstrated that the greatest increases in mortality occur in the elderly. Following the unusually hot summer of 2003 and the dramatic news from neighboring countries such as France, the Italian Minister of Health requested the Istituto Superiore di Sanità-Bureau of Statistics to undertake an epidemiologic study of mortality in Italy during Summer 2003 to investigate whether there had been an excess of deaths, with a particular focus on the elderly population. Materials and methods: Communal offices, which maintain vital statistics, were asked for the individual records of death of residents registered daily during the period 1 June–31 August 2003 and during the same period of 2002 for each of the 21 capitals of the Italian regions. As it was necessary to obtain mortality data quickly from many municipalities and to make the analysis as soon as possible, the method adopted was comparison of mortality counts during the heat wave with figures observed during the same period of the previous year. Results: Compared with 2002, between 1 June and 31 August 2003, there was an overall increase in mortality of 3134 (from 20,564 to 23,698). The greatest increase was among the elderly; 2876 deaths (92%) occurred among people aged 75 years and older, a more than one-fifth increase (21.3%, from 13.517 to 16.393%). The highest increases were observed in the northwestern cities, which are generally characterized by cold weather, and in individuals 75 years and older: Turin (44.9%), Trento (35.2%), Milan (30.6%), and Genoa (22.2%). Of note are also the increases observed in two southern cities, L’Aquila (24.7%) and Potenza (25.4%), which are located, respectively, at 700 and 800 m above see level. For Bari and Campobasso, both in the South, with a typically hot summer climate, the increase during the last 15 days of August was 186.2 and 450%, respectively. Conclusions: The relationship between mortality and discomfort due to climatic conditions as well as the short lag time give a clear public health message: preventive, social, and health care actions must be administered to the elderly and the frail to avoid excess deaths during heat waves.” Susanna Conti, Paola Meli, Giada Minelli, Renata Solimini, Virgilia Toccaceli, Monica Vichi, Carmen Beltrano, Luigi Perini, Environmental Research, Volume 98, Issue 3, July 2005, Pages 390–399, http://dx.doi.org/10.1016/j.envres.2004.10.009.

The 2003 heat wave as an example of summers in a greenhouse climate? Observations and climate model simulations for Basel, Switzerland – Beniston & Diaz (2004) “The heat wave that affected many parts of Europe during the course of summer 2003 may be a harbinger of summers that could occur more regularly in a future climate, under enhanced greenhouse gas concentrations. Switzerland was not exempt from the 2003 heat wave and, indeed, the previous absolute maximum temperature record dating back to the middle of the 20th century was exceeded by over 2 °C. Regional climate simulations undertaken for the European region emphasize the fact that summers will become progressively as hot as the 2003 event, such that, in the latter part of the 21st century, it is likely to become the norm. On the basis of this study, the 2003 event should be considered as a “shape of things to come” and thereby prompt timely decision making in terms of appropriate adaptation and mitigation strategies.” Martin Beniston, Henry F. Diaz, Global and Planetary Change, Volume 44, Issues 1–4, December 2004, Pages 73–81, http://dx.doi.org/10.1016/j.gloplacha.2004.06.006. [Full text]

The 2003 heat wave in Europe: A shape of things to come? An analysis based on Swiss climatological data and model simulations – Beniston (2004) “The 2003 heat wave that affected much of Europe from June to September bears a close resemblance to what many regional climate models are projecting for summers in the latter part of the 21st century. Model results suggest that under enhanced atmospheric greenhouse-gas concentrations, summer temperatures are likely to increase by over 4°C on average, with a corresponding increase in the frequency of severe heat waves. Statistical features of the 2003 heat wave for the Swiss site of Basel are investigated and compared to both past, 20th century events and possible future extreme temperatures based on model simulations of climatic change. For many purposes, the 2003 event can be used as an analog of future summers in coming decades in climate impacts and policy studies.” Beniston, M. (2004), The 2003 heat wave in Europe: A shape of things to come? An analysis based on Swiss climatological data and model simulations, Geophys. Res. Lett., 31, L02202, doi:10.1029/2003GL018857. [Full text]

Mortality in 13 French Cities During the August 2003 Heat Wave – Vandentorren et al. (2004) “We observed the daily trend in mortality rates during the 2003 heat wave in 13 of France’s largest cities. Mortality data were collected from July 25 to September 15 each year from 1999 through 2003. The conjunction of a maximum temperature of 35°C and a minimum temperature of 20°C was exceptional in 7 cities. An excess mortality rate was observed in the 13 towns, with disparities from +4% (Lille) to +142% (Paris).” Stéphanie Vandentorren, Florence Suzan, Sylvia Medina, Mathilde Pascal, Adeline Maulpoix, Jean-Claude Cohen, and Martine Ledrans Mortality in 13 French Cities During the August 2003 Heat Wave. American Journal of Public Health: September 2004, Vol. 94, No. 9, pp. 1518-1520, doi: 10.2105/AJPH.94.9.1518. [Full text]

Air pollution related deaths during the 2003 heat wave in the Netherlands – Fischer et al. (2004) “In the Netherlands an excess of 1000–1400 deaths was estimated due to the hot temperatures that occurred during the 2003 summer period. We estimated the number of deaths attributable to the ozone and Particular Matter (PM₁₀) concentrations in the summer period June–August 2003. Our calculations show that an excess of around 400–600 air pollution-related deaths may have occurred compared to an ‘average’ summer. These calculations suggest that in the Netherlands, a significant proportion of the deaths now being attributed to the hot summer weather can reasonably be expected to have been caused by air pollution.” Paul H. Fischer, Bert Brunekreef, Erik Lebret, Atmospheric Environment, Volume 38, Issue 8, March 2004, Pages 1083–1085, http://dx.doi.org/10.1016/j.atmosenv.2003.11.010.

The role of increasing temperature variability in European summer heatwaves – Schär et al. (2004) “Instrumental observations and reconstructions of global and hemispheric temperature evolution reveal a pronounced warming during the past 150 years. One expression of this warming is the observed increase in the occurrence of heatwaves. Conceptually this increase is understood as a shift of the statistical distribution towards warmer temperatures, while changes in the width of the distribution are often considered small. Here we show that this framework fails to explain the record-breaking central European summer temperatures in 2003, although it is consistent with observations from previous years. We find that an event like that of summer 2003 is statistically extremely unlikely, even when the observed warming is taken into account. We propose that a regime with an increased variability of temperatures (in addition to increases in mean temperature) may be able to account for summer 2003. To test this proposal, we simulate possible future European climate with a regional climate model in a scenario with increased atmospheric greenhouse-gas concentrations, and find that temperature variability increases by up to 100%, with maximum changes in central and eastern Europe.” Christoph Schär, Pier Luigi Vidale, Daniel Lüthi, Christoph Frei, Christian Häberli, Mark A. Liniger & Christof Appenzeller, Nature 427, 332-336 (22 January 2004) | doi:10.1038/nature02300. [Full text]