International climate agreements and climate change politics were the topics of my PhD research.
We all love summer, but it can become deadly if brings a heatwave.
In 10 seconds? Climate change makes extreme weather events more frequent and severe. Heat waves is arguably the most direct way in which climate change affects human wellbeing and causes many deaths worldwide.
How many people in the world are at risk of dying because of a heat wave? Recent study identified a threshold beyond which air temperature and humidity become deadly and suggested that already 30% of the world’s population live in the regions where this deadly threshold is exceeded for at least 20 days a year (read more here).
Which groups of population are at the greatest risk? Most heat wave deaths occur in people with pre-existing cardiovascular disease (heart attack and stroke) or chronic respiratory diseases. People with other pre-existing illnesses, as well as elderly people (especially women), mentally ill people, children and those in thermally stressful occupations are also vulnerable (read the science here).
It is going to get worse, right? Unfortunately yes. By 2100 the percentage of people leaving in potentially deadly hot weather conditions would increase to 48% under a scenario with drastic reductions of greenhouse gas emissions or to 74% under a scenario of growing emissions.
And in cold countries? Though nowadays people in the UK feel positive when thinking about hot weather, it is predicted that even there heat-related deaths would rise by around 257% by the 2050s from a recent annual baseline of around 2000 deaths.
How to combat these deadly heat waves and survive? First of all, carbon emissions causing anthropogenic climate change need to be cut (read more here on the rapid decarbonisation map).
Second, adaptation plans for heat waves should be elaborated. Researchers develop heat wave vulnerability maps to be considered in urban planning, since cities and towns may become urban heat islands during hotter weather.
Also researchers urge all governments to elaborate heat action plans for short, medium and long-term health protection measures. These plans should be taken and followed very seriously.
by Anna Firsova
Abstract: Daily numbers of deaths at a regional level were collected in 16 European countries. Summer mortality was analyzed for the reference period 1998-2002 and for 2003. More than 70,000 additional deaths occurred in Europe during the summer 2003. Major distortions occurred in the age distribution of the deaths, but no harvesting effect was observed in the months following August 2003. Global warming constitutes a new health threat in an aged Europe that may be difficult to detect at the country level, depending on its size. Centralizing the count of daily deaths on an operational geographical scale constitutes a priority for Public Health in Europe.
Pub.: 05 Feb '08, Pinned: 20 Jul '17
Abstract: Climate change can increase the risk of conditions that exceed human thermoregulatory capacity1, 2, 3, 4, 5, 6. Although numerous studies report increased mortality associated with extreme heat events1, 2, 3, 4, 5, 6, 7, quantifying the global risk of heat-related mortality remains challenging due to a lack of comparable data on heat-related deaths2, 3, 4, 5. Here we conducted a global analysis of documented lethal heat events to identify the climatic conditions associated with human death and then quantified the current and projected occurrence of such deadly climatic conditions worldwide. We reviewed papers published between 1980 and 2014, and found 783 cases of excess human mortality associated with heat from 164 cities in 36 countries. Based on the climatic conditions of those lethal heat events, we identified a global threshold beyond which daily mean surface air temperature and relative humidity become deadly. Around 30% of the world’s population is currently exposed to climatic conditions exceeding this deadly threshold for at least 20 days a year. By 2100, this percentage is projected to increase to ~48% under a scenario with drastic reductions of greenhouse gas emissions and ~74% under a scenario of growing emissions. An increasing threat to human life from excess heat now seems almost inevitable, but will be greatly aggravated if greenhouse gases are not considerably reduced.
Pub.: 19 Jun '17, Pinned: 11 Jul '17
Abstract: There is near unanimous scientific consensus that greenhouse gas emissions generated by human activity will change Earth's climate. The recent (globally averaged) warming by 0.5 degrees C is partly attributable to such anthropogenic emissions. Climate change will affect human health in many ways-mostly adversely. Here, we summarise the epidemiological evidence of how climate variations and trends affect various health outcomes. We assess the little evidence there is that recent global warming has already affected some health outcomes. We review the published estimates of future health effects of climate change over coming decades. Research so far has mostly focused on thermal stress, extreme weather events, and infectious diseases, with some attention to estimates of future regional food yields and hunger prevalence. An emerging broader approach addresses a wider spectrum of health risks due to the social, demographic, and economic disruptions of climate change. Evidence and anticipation of adverse health effects will strengthen the case for pre-emptive policies, and will also guide priorities for planned adaptive strategies.
Pub.: 15 Mar '06, Pinned: 11 Jul '17
Abstract: Heat waves pose serious health risks, and are expected to become more frequent, longer lasting, and more intense in the future under a changing climate. Yet, people in the UK seem to feel positive when thinking about hot weather. According to research on the affect heuristic, any positive or negative emotions evoked by potentially risky experiences may be used as cues to inform concerns about risk protection. If so, then their positive feelings toward hot weather might lead UK residents to lower intentions to adopt heat protection behaviors. Here, we examine the relationships between heat protection behaviors during the July 2013 UK heat wave and self-reports of having heard heat protection recommendations, feeling positive affect about heat, seeing heat protection measures as effective, and trusting the organizations making those recommendations. Responses to a national survey revealed that 55.1% of participants had heard heat protection recommendations during the 2013 UK heat wave. Those who reported having heard recommendations also indicated having implemented more heat protection behaviors, perceiving heat protection behaviors as more effective, feeling more positive about heat, and intending to implement more protection behaviors in future hot summers. Mediation analyses suggested that heat protection recommendations may motivate heat protection behaviors by increasing their perceived effectiveness, but undermine their implementation by evoking positive affect about hot weather. We discuss our findings in the context of the affect heuristic and its implications for heat protection communications.
Pub.: 31 Jan '15, Pinned: 10 Jul '17
Abstract: Assessing geographic variability in heat wave vulnerability forms the basis for planning appropriate targeted adaptation strategies. Given several recent deadly heatwaves in India, heat is increasingly being recognized as a public health problem. However, to date there has not been a country-wide assessment of heat vulnerability in India. We evaluated demographic, socioeconomic, and environmental vulnerability factors and combined district level data from several sources including the most recent census, health reports, and satellite remote sensing data. We then applied principal component analysis (PCA) on 17 normalized variables for each of the 640 districts to create a composite Heat Vulnerability Index (HVI) for India. Of the total 640 districts, our analysis identified 10 and 97 districts in the very high and high risk categories (> 2SD and 2-1SD HVI) respectively. Mapping showed that the districts with higher heat vulnerability are located in the central parts of the country. On examination, these are less urbanized and have low rates of literacy, access to water and sanitation, and presence of household amenities. Therefore, we concluded that creating and mapping a heat vulnerability index is a useful first step in protecting the public from the health burden of heat. Future work should incorporate heat exposure and health outcome data to validate the index, as well as examine sub-district levels of vulnerability.
Pub.: 31 Mar '17, Pinned: 06 Jul '17
Abstract: Recent climate projections predict an amplification of global warming and more frequent extreme events such as heat waves. Therefore, the adaptation of cities to counterbalance these adverse changes is urgent. Among available adaptation strategies, urban greening is a measure that is frequently encouraged to improve thermal comfort or energy demand, but whose impacts are not well known at the scale of cities. In this study we evaluate the effects of various urban greening scenarios based on urban climate simulations across the Paris area. The modelling relies on the Town Energy Balance model. The scenarios tested consist of an increase in ground-based vegetation or an implementation of green roofs on compatible buildings, or the two combined. Results show that increasing the ground cover has a stronger cooling impact than implementing green roofs on street temperatures, and even more so when the greening rate and the proportion of trees are important. Green roofs are however the most effective way to reduce energy consumption, not only in summer but also on an annual basis. The effects the various greening measures may have over different seasons is finally addressed in order to draw up a comprehensive inventory of the climatic impacts of such strategies.
Pub.: 02 Mar '17, Pinned: 11 Jul '17
Abstract: The Urban Heat Island (UHI) is a well-studied phenomenon, whereby urban areas are generally warmer than surrounding suburban and rural areas. The most direct effect on health from the UHI is due to heat risk, which is exacerbated in urban areas, particularly during heat waves. However, there may be health benefits from warming during colder months. This review highlights recent attempts to quantitatively estimate the health impacts of the UHI and estimations of the health benefits of UHI mitigation measures.Climate change, increasing urbanisation and an ageing population in much of the world, is likely to increase the risks to health from the UHI, particularly from heat exposure. Studies have shown increased health risks in urban populations compared with rural or suburban populations in hot weather and a disproportionate impact on more vulnerable social groups. Estimations of the impacts of various mitigation techniques suggest that a range of measures could reduce health impacts from heat and bring other benefits to health and wellbeing. The impact of the UHI on heat-related health is significant, although often overlooked, particularly when considering future impacts associated with climate change. Multiple factors should be considered when designing mitigation measures in urban environments in order to maximise health benefits and avoid unintended negative effects.
Pub.: 12 Jul '17, Pinned: 18 Jul '17
Abstract: Background Heat waves are among the extreme weather events and represent a growing health hazard for the population in Europe. According to the current climate studies, the probability of an increase and intensification of heat waves has been increasing for years. Particularly affected by exposure to unusually high heat are people whose organism is already weakened by age or illness. As the share of senior citizens in Germany continues to rise as a result of demographic change, the health effects of heat waves are gaining in importance. Objective Heat-induced morbidity and mortality can be effectively countered by information provision and timely initiation of preventive measures. The heat wave of the summer of 2003, which killed around 70000 people across Europe, led to the establishment of national heat warning systems and / or hot weather plans in much of Europe. In Germany, the heat warning system of the German Weather Service was set up nationwide in 2005. Thus, a 2-stage warning process can be comprehensively and timely inform people of an imminent heat wave, whereupon appropriate preventive measures can be initiated. In addition, it is recommended to establish a heat action plan which, in addition to heat warning, also takes into account comprehensive health intervention measures. Materials and methods This article outlines the background, significance and structure of a heat action plan according to the World Health Organization (WHO). This is based on the guidance document prepared in 2008 and the supplementary documents of the years 2009 and 2011. Results and discussion In order to ensure sustainable protection against heat-related health hazards, the World Health Organization (WHO) recommends the introduction of a national heat action plan for its Member States. There are fundamental differences between a heat warning system and a heat action plan. While the warning of a brief heat period is the central task of the heat warning system, the heat action plan follows an integrative approach that combines short, medium and long-term health protection measures within a common framework.
Pub.: 08 Jun '17, Pinned: 06 Jul '17
Abstract: National heatwave plans are aimed at reducing the avoidable human health consequences due to heatwaves, by providing warnings as well as improving communication between relevant stakeholders. The objective of this study was to assess the perceptions of key stakeholders within plans in Belgium and The Netherlands on their responsibilities, the partnerships, and the effectiveness of the local implementation in Brussels and Amsterdam. Key informant interviews were held with stakeholders that had an important role in development of the heatwave plan in these countries, or its implementation in Brussels or Amsterdam. Care organisations, including hospitals and elderly care organisations, had a lack of familiarity with the national heatwave plan in both cities, and prioritised heat the lowest. Some groups of individuals, specifically socially isolated individuals, are not sufficiently addressed by the current national heatwave plans and most local plans. Stakeholders reported that responsibilities were not clearly described and that the national plan does not describe tasks on a local level. We recommend to urgently increase awareness on the impact of heat on health among care organisations. More emphasis needs to be given to the variety of heat-risk groups. Stakeholders should be involved in the development of updates of the plans.
Pub.: 12 Nov '16, Pinned: 11 Jul '17
Abstract: Many sea-level rise (SLR) assessments focus on populations presently inhabiting vulnerable coastal communities1, 2, 3, but to date no studies have attempted to model the destinations of these potentially displaced persons. With millions of potential future migrants in heavily populated coastal communities, SLR scholarship focusing solely on coastal communities characterizes SLR as primarily a coastal issue, obscuring the potential impacts in landlocked communities created by SLR-induced displacement. Here I address this issue by merging projected populations at risk of SLR1 with migration systems simulations to project future destinations of SLR migrants in the United States. I find that unmitigated SLR is expected to reshape the US population distribution, potentially stressing landlocked areas unprepared to accommodate this wave of coastal migrants—even after accounting for potential adaptation. These results provide the first glimpse of how climate change will reshape future population distributions and establish a new foundation for modelling potential migration destinations from climate stressors in an era of global environmental change.
Pub.: 17 Apr '17, Pinned: 17 Jul '17
Abstract: The ensemble results of CMIP5 climate models that applied the RCP4.5 and RCP8.5 scenarios have been used to investigate climate change and temperature extremes in the Middle East and North Africa (MENA). Uncertainty evaluation of climate projections indicates good model agreement for temperature but much less for precipitation. Results imply that climate warming in the MENA is strongest in summer while elsewhere it is typically stronger in winter. The summertime warming extends the thermal low at the surface from South Asia across the Middle East over North Africa, as the hot desert climate intensifies and becomes more extreme. Observations and model calculations of the recent past consistently show increasing heat extremes, which are projected to accelerate in future. The number of warm days and nights may increase sharply. On average in the MENA, the maximum temperature during the hottest days in the recent past was about 43 °C, which could increase to about 46 °C by the middle of the century and reach almost 50 °C by the end of the century, the latter according to the RCP8.5 (business-as-usual) scenario. This will have important consequences for human health and society.
Pub.: 23 Apr '16, Pinned: 17 Jul '17
Abstract: The impact of major heatwave shocks on population morbidity and mortality has become an urgent public health concern. However, Current heatwave warning systems suffer from a lack of validation and an inability to provide accurate health risk warnings in a timely way. Here we conducted a correlation and linear regression analysis to test the relationship between heat stroke internet searches and heat stroke health outcomes in Shanghai, China, during the summer of 2013. We show that the resulting heatstroke index captures much of the variation in heat stroke cases and deaths. The correlation between heat stroke deaths, the search index and the incidence of heat stroke is higher than the correlation with maximum temperature. This study highlights a fast and effective heatwave health warning indicator with potential to be used throughout the world.
Pub.: 22 Nov '16, Pinned: 11 Jul '17
Abstract: UHI is the most studied phenomenon of climate change and refers to the increased ambient temperature of cities compared to rural settings. Implementation of reflective materials to urban structures, such as roads and pavements, reduces the surface and ambient temperature and contributes to counterbalance the impact of the phenomenon. The present paper describes the design and the experimental evaluation of a large scale implementation of cool asphaltic and concrete pavements in a major traffic axis of Western Athens covering a total zone of 37,000 m2. To our knowledge, this project is one of the largest urban mitigation projects in the world. Extended monitoring was performed in the area during the entirety of the summer period, while Computational Fluid Dynamics (CFD) simulation was used to evaluate the thermal impact of the application. It was concluded that the use of cool non-aged asphalt can reduce the ambient temperature by up to 1.5 °C and the maximum surface temperature reduction could reach 11.5 °C, while the thermal comfort conditions can improve considerably. Ageing phenomena may reduce substantially and up to 50% the mitigation potential of cool asphaltic materials.
Pub.: 16 Mar '17, Pinned: 24 Jul '17
Abstract: Older adults are highly vulnerable to the detriment of extreme weather. The rapid non-linear increase in heat-related morbidity is difficult to quantify, hindering the attribution of direct effects of exposure on severe health outcomes. We examine the effects of ambient temperatures on heat-related hospitalizations (HH) among the elderly in presence of strong seasonality and by assessing the effects caused by the first and subsequent seasonal heatwaves. We empirically derived the thresholds for a heatwave episode in Boston MSA based on 16 years of daily observations. We compared the health risks of heatwaves using the proposed and four alternative definitions. 701 cases of HH in older residents of Boston area were examined using harmonic regression models, designed to capture the non-linear effects of ambient temperatures and heatwave episodes when the night-time temperature is above 65.5 °F for 3 consecutive nights. The overall relative risk of HH associated with a heatwave episode was 6.9 [95%CI:4.8-9.8]. The relative risk of HH associated with the first heatwave increases up to 13.3 [95%CI:7.4-24.0]. The risk declined to 3.7 [95%CI:2.4-5.8] for the subsequent heatwave. Four other commonly used heatwave definitions confirmed these findings. Public health actions have to target the first heatwave to maximize the impact of preventive measures.
Pub.: 12 Jan '17, Pinned: 11 Jul '17
Abstract: The formation of an urban heat island (UHI) is one of the most common impacts of the urbanization process. To mitigate the effects of UHI, the planning of urban forests (e.g., creation of parks, forests and afforestation streets) has been the major tool applied in this context. Thus, the aim of this study is to evaluate the spatial and temporal distribution of heat islands in Vila Velha, ES, Brazil using the mono-window algorithm. The study followed these methodological steps: 1) mapping of urban green areas through a photointerpretation screen; 2) application of the mono-window algorithm to obtain the spatial and temporal patterns of land surface temperature (LST); 3) correlation between LST and the normalized difference vegetation index (NDVI) and normalized difference build-up index (NDBI); 4) application of ecological evaluation index. The results showed that the mean values of LST in urban areas were at least 2.34 to 7.19°C higher than undeveloped areas. Moreover, the positive correlation between LST and NDBI showed an amplifying effect of the developed areas for UHI, while areas with a predominance of vegetation attenuated the effect of UHI. Urban centers, clustered in some parts of the city, received the worst ecological assessment index. Finally, the adoption of measures to guide the urban forest planning within urban centers is necessary to mitigate the effect of heat islands and provide thermal comfort in urban areas.
Pub.: 12 Jul '17, Pinned: 18 Jul '17
Abstract: The frequency and intensity of urban heatwaves (UHWs) have been growing worldwide due to climate change and the exacerbating effects of urban heat islands (UHIEs). UHWs have many negative impacts, including excess negative health outcomes (e.g. morbidity), energy (consumption and peak demand) and water consumption. Most studies have evaluated these impacts separately even though there is an interplay between them. The study assessed the daily excess morbidity, energy demand and consumption, and water supply in the Adelaide metropolitan region during heatwaves, between January 2008 and March 2014. The assessment quantifies the thresholds and the increase in each impact relative to temperature increase. The demonstrated negative impacts on public health, and energy and water resources, potentially exacerbated by UHIEs, justify the importance of interdisciplinary research and integrated policy changes on the mitigation of and adaptation to heatwaves.
Pub.: 30 Dec '16, Pinned: 11 Jul '17
Abstract: We investigate acclimatization effects on outdoor thermal perception. Steady-state conditions were ensured by a prolonged stay of participants (N = 16) in a test chamber prior to the subjects' exposure to outdoors, i.e. after five consecutive hours under thermal comfort conditions indoors. After that, subjects walked in a controlled pace around the external precincts of the facility and were asked to vote on their thermal sensation and preference according to a standard questionnaire: a) immediately, b) 15 min and c) 30 min after they left the controlled indoor environment. Altogether 36 sessions were performed with varying outdoor conditions over winter, spring, and summer 2015. We evaluate acclimatization effects on the subjects' thermal perception against predictions of the outdoor thermal conditions in terms of UTCI (Universal Thermal Climate Index) and the derived DTS (Dynamic Thermal Sensation). ANOVA results showed that UTCI conditions remained unchanged throughout the 30-min exposure time outdoors, but differed between seasons, whereas the subjects' thermal perception votes differed both between seasons and the times of votes. Reduced thermal sensitivity was noticed in winter and spring at the first vote, resulting in greater prediction bias (underestimation), which was attenuated at higher temperatures and during longer exposure times. An initial overshooting at the first vote towards cool response occurred at moderate temperatures in summer, increasing bias (overestimation), which was also attenuated with increasing temperature and time of exposure. Acclimatization to a heatwave in summer lead to enhanced heat tolerance just after it, with acclimatization loss in the subsequent session.
Pub.: 08 Feb '17, Pinned: 11 Jul '17
Abstract: Heatwaves is the most hazardous natural disaster in Australia and its health impacts need to be well unveiled, but how to properly define a heatwave is still debatable. This study aimed to identify which type of heatwave is more detrimental to health and to elucidate which temperature indicator is more suitable for heatwave definition and early warning.We categorized temperature into extremely-hot and not-extremely-hot, and extremely-hot temperature refers to temperature at least ≥96th percentile of the monthly temperature distribution, and accordingly, heatwaves were categorized into four types: 1) Type I: extremely-hot days followed by extremely-hot nights (HWboth); 2) Type II: extremely-hot days followed by not-extremely-hot nights (HWday); 3) Type III: not-extremely-hot days followed by extremely-hot nights (HWnight); and 4) Type IV: not-extremely-hot days followed by not-extremely-hot nights (HWwarm). A Poisson regression allowing for over-dispersion was used to examine the relationship between different types of heatwaves and mortality in Sydney, Melbourne and Brisbane using the data from 1988 to 2011.Mortality in Brisbane increased significantly during HWboth and HWwarm, and mortality in Melbourne increased significantly during HWboth and HWday. For Sydney, HWboth, HWwarm, and HWday were all associated with mortality increase, although no appreciable difference in the magnitudes of mortality increase among these three heatwave types was observed. HWnight was not associated with any significant mortality increase in these cities. Mean temperature is the best temperature indicator for heatwaves in Brisbane and maximum temperature is the best temperature indicator for heatwaves in Melbourne.Extremely-hot days rather than extremely-hot nights played a critical role in heatwave-related mortality. City-specific heatwave early warning may be optimal for Australia.
Pub.: 12 May '17, Pinned: 11 Jul '17
Abstract: Data on the health impacts of heatwaves in infants are limited, and this study aimed to examine how heatwaves affect hospital admissions in infants.A quasi-Poisson generalized additive model was used to assess the effects of heatwaves on hospital admissions in infants from 1st January 2005 to 31st December 2015 in Brisbane, Australia, using a series of heatwave definitions after controlling for possible confounders. A case-only analysis was conducted to examine the possible modification effects of personal and community characteristics on the heatwaves effects on infants' hospital admissions.There was no significant increase in infants' hospital admissions when heatwave intensity was defined as mean temperature ≥90(th) percentile or ≥95th percentile of the mean temperature across the study period. When heatwave intensity increased to ≥97th percentile, infants' hospital admissions increased significantly (RR: 1.05, 95% CI: 1.01, 1.10), and this increase raised with the increase of heatwave duration. No modification effect of gender, indigenous status, or Socio-Economic Indexes for Areas (SEIFA) level on heatwave effect was observed.Infants in Brisbane were sensitive to intense heatwaves, and future heat early warning system based on a local evidence-based heatwave definition is needed to protect infants from heatwave impacts. Community-based heatwave adaptation programs aiming at raising the awareness of the adverse health impacts of intense heatwaves among infants' caregivers may relieve the postnatal health care demand in infants.
Pub.: 21 Jun '17, Pinned: 11 Jul '17
Abstract: Human emissions of greenhouse gases are already changing our climate. This paper provides an overview of the relation between climate change and weather extremes, and examines three specific cases where recent acute events have stimulated debate on the potential role of climate change: the European heatwave of 2003; the risk of inland flooding, such as recently in Central Europe and Great Britain; and the harsh Atlantic hurricane seasons of 2004 and 2005. Furthermore, it briefly assesses the relation between climate change and El Niño, and the potential of abrupt climate change. Several trends in weather extremes are sufficiently clear to inform risk reduction efforts. In many instances, however, the potential increases in extreme events due to climate change come on top of alarming rises in vulnerability. Hence, the additional risks due to climate change should not be analysed or treated in isolation, but instead integrated into broader efforts to reduce the risk of natural disasters.
Pub.: 04 Mar '06, Pinned: 07 Jul '17
Abstract: The frequency and intensity of extreme heat wave events have increased in the past several decades and are likely to continue to increase in the future under the influence of human-induced climate change. Exposure refers to people, property, systems, or other elements present in hazard zones that are thereby subject to potential losses. Exposure to extreme heat and changes therein are not just determined by climate changes but also population changes. Here we analyze output for three scenarios of greenhouse gas emissions and socio-economic growth to estimate future exposure change taking account of both climate and population factors. We find that for the higher emission scenario (RCP8.5-SSP3), the global exposure increases nearly 30-fold by 2100. The average exposure for Africa is over 118 times greater than it has been historically, while the exposure for Europe increases by only a factor of four. Importantly, in the absence of climate change, exposure is reduced by 75-95% globally and across all geographic regions, as compared with exposure under the high emission scenario. Under lower emission scenarios RCP4.5-SSP2 and RCP2.6-SSP1, the global exposure is reduced by 65% and 85% respectively, highlighting the efficacy of mitigation efforts in reducing exposure to extreme heat.
Pub.: 08 Mar '17, Pinned: 06 Jul '17
Abstract: Heat-waves have a substantial public health burden. Understanding spatial heterogeneity at a fine spatial scale in relation to heat and related mortality is central to target interventions towards vulnerable communities.To determine the spatial variability of heat-wave-related mortality risk among elderly in Paris, France at the census block level. We also aimed to assess area-level social and environmental determinants of high mortality risk within Paris.We used daily mortality data from 2004 to 2009 among people aged >65 at the French census block level within Paris. We used two heat wave days' definitions that were compared to non-heat wave days. A Bernoulli cluster analysis method was applied to identify high risk clusters of mortality during heat waves. We performed random effects meta-regression analyses to investigate factors associated with the magnitude of the mortality risk.The spatial approach revealed a spatial aggregation of death cases during heat wave days. We found that small scale chronic PM10 exposure was associated with a 0.02 (95% CI: 0.001; 0.045) increase of the risk of dying during a heat wave episode. We also found a positive association with the percentage of foreigners and the percentage of labor force, while the proportion of elderly people living in the neighborhood was negatively associated. We also found that green space density had a protective effect and inversely that the density of constructed feature increased the risk of dying during a heat wave episode.We showed that a spatial variation in terms of heat-related vulnerability exists within Paris and that it can be explained by some contextual factors. This study can be useful for designing interventions targeting more vulnerable areas and reduce the burden of heat waves.
Pub.: 21 Mar '17, Pinned: 06 Jul '17
Abstract: There are scarce studies of time series that analysed the short-term association between emergency hospital admissions due to Alzheimer's disease (AD) and environmental factors. The objective is to analyse the effect of heat waves, noise and air pollutants on urgent hospital admissions due to AD in Madrid.Longitudinal ecological time series study was performed. The dependent variable was the emergency AD hospital admissions occurred in Madrid during the period 2001-2009. Independent variables were: Daily mean concentrations (μg/m3) of air pollutants (PM2.5 and PM10; O3 and NO2); maximum daily temperature (°C) and daily and night noise levels (dB(A)). Relative Risk (RR) for an increment in interquartile range, and Attributable Risk (AR) values were calculated through GLM with Poisson link.Our findings indicated that only PM2.5 concentrations at lag 2 with a RR: 1.38 (95% CI: 1.15-1.65); AR 27.5% (95% CI: 13.0-39.4); and heat wave days at lag 3 with a RR: 1.30 (95% CI: 1.12-1.52); AR 23.1% (95% CI: 10.7-34.2) were associated with AD hospital admissions.A reduction in AD patients' exposure levels to PM2.5 and special care of such patients during heat wave periods could result in a decrease in both emergency AD admissions and the related health care costs.
Pub.: 28 Mar '17, Pinned: 06 Jul '17
Abstract: Many studies have investigated the associations between heat waves, ambient temperature, cold spells, and mortality or morbidity. Some studies have utilized effect modification to reveal the factors that increase an individual's susceptibility to temperature extremes, which can then be used to reshape public policy. In this study, we used a time-stratified case-crossover technique to examine how individual- and regional-scale characteristics modified heat wave-related impacts on mortality rates in Seoul, South Korea, between 2009 and 2012. We defined a heat wave as having at least two consecutive days with a daily mean temperature greater than or equal to the 95th percentile recorded in each of Seoul's twenty-five districts. At the individual scale, citizens classified as belonging to a lower education group had a higher vulnerability to heat wave-related morbidity or mortality [odds ratio (OR) 1.261; 95% confidence interval (CI): 1.034-1.538]. At a regional scale, death during heat waves was more likely to occur in districts with a high deprivation index (OR=1.194; 95% CI: 1.028-1.388). And a low proportion of green space around buildings (OR=1.178; 95% CI: 1.016-1.366), a low proportion of rooftop green space (OR=1.207; 95% CI: 1.042-1.399), or those that had fewer hospitals (OR=1.186; 95% CI: 1.019-1.379). Our data show that mortality during heat waves is more likely where these individual and regional-scale vulnerabilities overlap. Our findings support evidence of mortality impacts from heat waves and provide a basis for selection to policy makers choose on the target groups to reduce the public health burden of heat waves.
Pub.: 07 Apr '17, Pinned: 06 Jul '17
Abstract: Under the background of global warming, occurrence of heat waves has increased in most part of Europe, Asia and Australia along with enhanced ozone level. In this paper, observational air temperature and surface ozone in the Yangtze River Delta (YRD) region of China during summer of 2013, and the regional chemistry-climate model (RegCM-CHEM4) were applied to explore the relationship between heat wave and elevated ground-level ozone. Observations indicated that YRD experienced severe heat waves with maximum temperature up to 41.1 °C, 6.1 °C higher than the definition of heat wave in China, and can last for as long as 27 days. Maximum ozone reached 160.5 ppb, exceeding the national air quality standard (secondary level) as 74.7 ppb. Moreover, ozone was found to increase at a rate of 4–5 ppb K− 1 within the temperature range of 28–38 °C, but decrease by a rate of − 1.3 ~ − 1.7 ppb K− 1 under extremely high temperature. A typical heat wave case (HW: 24/7–31/7) and non-heat wave case (NHW: 5/6–12/6) were selected to investigate the mechanism between heavy ozone and heat waves. It was found that chemical reactions play the most important role in ozone formation during HW days, which result in 12 ppb ozone enhancement compared to NHW days. Chemical formation of ozone can be influenced by several factors. During heat waves, a more stagnant condition, controlled by anti-cyclone with sink airflow, led to less water vapor in YRD from south and contributed to less cloud cover, which favored a strong solar radiation environment and ozone significantly increasing. High temperature also slightly promote the effect of vertical turbulence and horizontal advection, which beneficial to ozone remove, but the magnitude is much smaller than chemical effect. Our study suggests that the chemical reaction will potentially lead to substantial elevated ozone in a warmer climate, which should be taken into account in future ozone related issues.
Pub.: 22 Apr '17, Pinned: 06 Jul '17
Abstract: To investigate the relationship between temperature extremes and daily number of deaths in Jinan, a temperate city in northern China.Data ondaily number of deaths and meteorological variables over the period of 2011-2014 were collected. Cold spells or heat waves were defined as ≥3 consecutive days with mean temperature ≤5th percentile or ≥95th percentile, respectively. We applied a time-series adjusted Poisson regression to assess the effects of extreme temperature on deaths.There were 152 150 non-accidental deaths over the study period in Jinan, among which 87 607 people died of cardiovascular disease, 11 690 of respiratory disease, 33 001 of stroke and 6624 of chronic obstrutive pulmonary disease (COPD). Cold spells significantly increased the risk of deaths due to non-accidental mortality (RR 1.08, 95% CI 1.06 to 1.11), cardiovascular disease (RR 1.06, 95% CI 1.03 to 1.10), respiratory disease (RR 1.19, 95% CI 1.11 to 1.27), stroke (RR 1.11, 95% CI 1.06 to 1.17) and COPD (RR 1.27, 95% CI 1.16 to 1.38). Heat waves significantly increased the risk of deaths due to non-accidental mortality (RR 1.02, 95% CI 1.00 to 1.05), cardiovascular disease (RR 1.03, 95% CI 1.00 to 1.06) and stroke (RR 1.06, 95% CI 1.00 to 1.13). The elderly were more vulnerable during heat wave exposure; however, vulnerability to cold spell was the same for the whole population regardless of age and gender.Both cold spells and heat waves have increased the risk of death in Jinan, China.
Pub.: 04 May '17, Pinned: 06 Jul '17