The health effects of hotter summers and heat waves in the population of the United Kingdom: a review of the evidence

Unequal distributions of crowdsourced weather data in England and Wales

Personal weather stations (PWS) can provide useful data on urban climates by densifying the number of weather measurements across major cities. They do so at a lower cost than official weather stations by national meteorological services. Despite the increasing use of PWS data, little attention has yet been paid to the underlying socio-economic and environmental inequalities in PWS coverage. Using social deprivation, demographic, and environmental indicators in England and Wales, we characterize existing inequalities in the current coverage of PWS. We find that there are fewer PWS in more deprived areas which also observe higher proportions of ethnic minorities, lower vegetation coverage, higher building height and building surface fraction, and lower proportions of inhabitants under 65 years old. This implies that data on urban climate may be less reliable or more uncertain in particular areas, which may limit the potential for climate adaptation and empowerment in those communities.

Heat wave exposure and increased heat-related hospitalizations in young children in South Korea: A time-series study

BACKGROUND

Numerous studies have investigated the association between heat wave exposure increased heat-related hospitalizations in the general population. However, little is known about heat-related morbidity in young children who are more vulnerable than the general population. Therefore, we aimed to evaluate the association between hospitalization for heat-related illness in children and heat wave exposure in South Korea.

METHODS

We used the National Health Insurance Service (NHIS) database, which provides medical records from 2015 to 2019 in South Korea. We defined daily hospitalizations for heat-related illness of children younger than five years during the summer period (June to August). We considered the definition of heat waves considering the absolute temperature and percentile. A total of 12 different heat waves were used. A time-series analysis was used to investigate the association between heat wave exposure and heat-related hospitalization among children younger than five years. We used a two-stage design involving a meta-analysis after modeling by each region.

RESULTS

We included 16,879 daily heat-related hospitalizations among children younger than five years. Overall, heat wave exposure within two days was most related for heat-related hospitalizations in young children. The relative risk (RR) due to heat wave exposure within two days (lag2) (12 definitions: 70th to 90th percentile of maximum temperature) ranged from 1.038 (95% confidence interval (CI): 0.971, 1.110) to 1.083 (95% CI: 1.036, 1.133). We found that boys were more vulnerable to heat exposure than girls. In addition, we found that urban areas were more vulnerable to heat exposure than rural areas.

CONCLUSIONS

In our study, heat wave exposure during summer was found to be associated with an increased risk of hospitalization for heat-related illness among children younger than five years. Our findings suggest the need for summer heat wave management and prevention for children.

High average daily temperature in summer and the incidence of thrombolytic treatment for acute ischemic stroke

INTRODUCTION

Meteorological factors can increase stroke risk; however, their impact is not precisely understood. Heat waves during summer increase total mortality. Therefore, we hypothesized that the average daily temperature in summer may correlate with the incidence of thrombolytic treatment for acute ischemic stroke in Budapest and Pest County, Hungary.

METHODS

We analyzed the relationship between the average daily temperature in summer months and the daily number of thrombolytic treatments (TT) performed with the indication of acute ischemic stroke between 1st June and 31st August each year from 2007 to 2016. The analysis was also performed after the omission of the data of the last day of the months due to possible psychosocial impact reported in our previous study. Spearman's correlation was used for statistical analysis.

RESULTS

No significant correlation was found between the average summer daily temperature and the number of TT in the entire sample of the 10-year period. When omitting the data of the last day of each month, positive correlations were suspected in 2014 (r=0.225, P=0.034) and 2015 (r=0.276, P=0.009).

CONCLUSION

Our findings did not confirm an association between the average daily temperature in summer and the daily number of TT throughout the examined 10-year period. However, importantly, in 2014 and 2015, the years with the highest average daily temperatures in this period, a positive correlation was found. The level of correlation is modest, indicating that risk factors, both meteorological and non-meteorological, other than the average temperature, play equally important roles in determining the incidence of thrombolytic treatment for acute ischemic stroke on the population level.

Effect of ultraviolet radiation on immature stages of Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus mosquitoes

Background & objectives

Understanding the influence of ultraviolet light on organisms is important for examining the hazards of exposure to ultraviolet (UV) light. However, little is known about the biological toxicity of ultraviolet light against mosquitoes, which are regularly exposed to UV light. This study was planned to determine the impact of UV radiation on different aquatic stages of Aedes aegypti, Anopheles stephensi and Culex quinquefaciatus mosquitoes.

Methods

We exposed I/II instar larvae, III/IV instar larvae and pupae of Ae. aegypti, An. stephensi and Cx. quinquefaciatus mosquitoes to UV radiation of 253 nm wavelength in a closed chamber of 30×30 cm. The exposure was done for different time intervals viz. 1, 2, 3, 4 minutes and so on. Development of larvae/pupae to adult stage was monitored daily and mortality, if any, was recorded.

Results

Development of I/II instar larvae of Ae. aegypti and Cx. quinquefasciatus to pupal stage was unsuccessful at an exposure time of one minute while only 1.7% pupation occurred in I/II instar larvae of Ae. aegypti upon similar exposure. When III/IV stage larvae were exposed to UV light, pupal development occurred only at 30seconds and one-minute exposure in An. stephensi and Cx. quinquefaciatus but in Ae. aegypti, no pupation occurred with one-minute exposure. With four-minute UV exposure of pupae, no adult emerged in Ae. aegypti; 33.3% adult emerged in An. stephensi and 66.7% adult emerged in Cx. quinquefaciatus.

Interpretation & conclusion

Our results show that UV radiation results in developmental arrest of Ae. aegypti, An. stephensi and Cx. quinquefaciatus mosquitoes.

Variability of heat stress using the UrbClim climate model in the city of Seville (Spain): mitigation proposal

Climate change is creating an increase in temperatures, which is harming the quality of life of people all over the world, particularly those with minimal financial resources. While 30% of the world's population is now vulnerable to extreme heat, estimates show that ratio will rise to 74% in the next 20 years, according to forecasts. Using the UrbClim climate model, this study examines the space-time variability of the heat stress index (HI) in different local climate zones (LCZs), as well as how heat wave conditions might affect this index based on land use and land cover. To that end, Seville, in Southern Spain, was investigated during the summer of 2017, when it had four heat waves. The following indices were considered for each urban sub-area: Normalized Difference Vegetation, Proportion Vegetation, Normalized Difference Built, and Urban Index. The goal is to conduct a statistical analysis of the link between the aforementioned elements and the heat stress index in order to recommend mitigation and resilience techniques. Our findings showed that compact and industrial LCZs (2, 3, and 10) are less resistant to HI than open and rural regions (5, 6, B, D, and G), which are more resistant to HI due to higher vegetation rates. The heat wave condition exacerbates the HI in all LCZs. As a result, initiatives such as enhancing open space, increasing green space, or using green roofs and façades might alleviate heat stress and improve people's quality of life.

Gender inequalities in heat-related mortality in the Czech Republic

It is acknowledged that climate change exacerbates social inequalities, and women have been reported as more vulnerable to heat than men in many studies in Europe, including the Czech Republic. This study aimed at investigating the associations between daily temperature and mortality in the Czech Republic in the light of a sex and gender perspective, taking into account other factors such as age and marital status. Daily mean temperature and individual mortality data recorded during the five warmest months of the year (from May to September) over the period 1995-2019 were used to fit a quasi-Poisson regression model, which included a distributed lag non-linear model (DLNM) to account for the delayed and non-linear effects of temperature on mortality. The heat-related mortality risks obtained in each population group were expressed in terms of risk at the 99th percentile of summer temperature relative to the minimum mortality temperature. Women were found generally more at risk to die because of heat than men, and the difference was larger among people over 85 years old. Risks among married people were lower than risks among single, divorced, and widowed people, while risks in divorced women were significantly higher than in divorced men. This is a novel finding which highlights the potential role of gender inequalities in heat-related mortality. Our study underlines the relevance of including a sex and gender dimension in the analysis of the impacts of heat on the population and advocates the development of gender-based adaptation policies to extreme heat.

'I don't really associate climate change with actual people's health': a qualitative study in England of perceptions of climate change and its impacts on health

OBJECTIVES

The health impacts of climate change are increasing, but qualitative evidence on people's perceptions is limited. This qualitative study investigated people's perceptions of climate change and its impacts on health.

STUDY DESIGN

This was an online study using semistructured interviews.

METHODS

A total of 41 semistructured interviews were conducted in 2021 with members of the public aged ≥15 years living in England, recruited via community-based groups. Data were analysed using reflexive thematic analysis.

RESULTS

Participants were concerned about climate change, which was often perceived as extreme weather events happening elsewhere. Changes in the UK's seasons and weather patterns were noted, but participants were uncertain whether these changes resulted from climate change. Participants often struggled to identify health impacts of climate change; where health impacts were described, they tended to be linked to extreme weather events outside the United Kingdom and their associated threats to life. The mental health impacts of such events were also noted.

CONCLUSIONS

The study found that most participants did not perceive climate change to be affecting people's health in England. This raises questions about whether framing climate change as a health issue, an approach advocated for countries less exposed to the direct effects of climate change, will increase its salience for the British public.

Spatiotemporal analysis of the surface urban heat island (SUHI), air pollution and disease pattern: an applied study on the city of Granada (Spain)

There is worldwide concern about how climate change -which involves rising temperatures- may increase the risk of contracting and developing diseases, reducing the quality of life. This study provides new research that takes into account parameters such as land surface temperature (LST), surface urban heat island (SUHI), urban hotspot (UHS), air pollution (SO₂, NO₂, CO, O₃ and aerosols), the normalized difference vegetation index (NDVI), the normalized difference building index (NDBI) and the proportion of vegetation (PV) that allows evaluating environmental quality and establishes mitigation measures in future urban developments that could improve the quality of life of a given population. With the help of Sentinel 3 and 5P satellite images, we studied these variables in the context of Granada (Spain) during the year 2021 to assess how they may affect the risk of developing diseases (stomach, colorectal, lung, prostate and bladder cancer, dementia, cerebrovascular disease, liver disease and suicide). The results, corroborated by the statistical analysis using the Data Panel technique, indicate that the variables LST, SUHI and daytime UHS, NO₂, SO₂ and NDBI have important positive correlations above 99% (p value: 0.000) with an excess risk of developing these diseases. Hence, the importance of this study for the formulation of healthy policies in cities and future research that minimizes the excess risk of diseases.

Climate toxicity: An increasingly relevant clinical issue in Cancer Care

In recent years the terms time and financial toxicities have entered the vocabulary of cancer care. We would like to introduce another toxicity: climate toxicity. Climate toxicity is a double-edge sword in cancer care. Increasing cancer risk by exposure to carcinogens, and consequently increasing treatment requirements leads to ever growing damage to our environment. This article assesses the impact of climate change on patients, the climate toxicity caused by both healthcare workers and healthcare facilities, and suggests actions that may be taken mitigate them.

The Impact of Ambient Temperature on Cardiorespiratory Mortality in Northern Greece

It is well-established that exposure to non-optimum temperatures adversely affects public health, with the negative impact varying with latitude, as well as various climatic and population characteristics. This work aims to assess the relationship between ambient temperature and mortality from cardiorespiratory diseases in Eastern Macedonia and Thrace, in Northern Greece. For this, a standard time-series over-dispersed Poisson regression was fit, along with a distributed lag nonlinear model (DLNM), using a maximum lag of 21 days, to capture the non-linear and delayed temperature-related effects. A U-shaped relationship was found between temperature and cardiorespiratory mortality for the overall population and various subgroups and the minimum mortality temperature was observed around the 65th percentile of the temperature distribution. Exposure to extremely high temperatures was found to put the highest risk of cardiorespiratory mortality in all cases, except for females which were found to be more sensitive to extreme cold. It is remarkable that the highest burden of temperature-related mortality was attributed to moderate temperatures and primarily to moderate cold. The elderly were found to be particularly susceptible to both cold and hot thermal stress. These results provide new evidence on the health response of the population to low and high temperatures and could be useful to local authorities and policy-makers for developing interventions and prevention strategies for reducing the adverse impact of ambient temperature.

Toward informatics-enabled preparedness for natural hazards to minimize health impacts of climate change

Natural hazards (NHs) associated with climate change have been increasing in frequency and intensity. These acute events impact humans both directly and through their effects on social and environmental determinants of health. Rather than relying on a fully reactive incident response disposition, it is crucial to ramp up preparedness initiatives for worsening case scenarios. In this perspective, we review the landscape of NH effects for human health and explore the potential of health informatics to address associated challenges, specifically from a preparedness angle. We outline important components in a health informatics agenda for hazard preparedness involving hazard-disease associations, social determinants of health, and hazard forecasting models, and call for novel methods to integrate them toward projecting healthcare needs in the wake of a hazard. We describe potential gaps and barriers in implementing these components and propose some high-level ideas to address them.

Temperature-related mortality and associated vulnerabilities: evidence from Scotland using extended time-series datasets

BACKGROUND

Adverse health impacts have been found under extreme temperatures in many parts of the world. The majority of such research to date for the UK has been conducted on populations in England, whilst the impacts of ambient temperature on health outcomes in Scottish populations remain largely unknown.

METHODS

This study uses time-series regression analysis with distributed lag non-linear models to characterise acute relationships between daily mean ambient temperature and mortality in Scotland including the four largest cities (Aberdeen, Dundee, Edinburgh and Glasgow) and three regions during 1974-2018. Increases in mortality risk under extreme cold and heat in individual cities and regions were aggregated using multivariate meta-analysis. Cold results are summarised by comparing the relative risk (RR) of death at the 1st percentile of localised temperature distributions compared to the 10th percentile, and heat effects as the RR at the 99th compared to the 90th percentile.

RESULTS

Adverse cold effects were observed in all cities and regions, and heat effects were apparent in all cities and regions except northern Scotland. Aggregate all-cause mortality risk in Scotland was estimated to increase by 10% (95% confidence interval, CI: 7%, 13%) under extreme cold and 4% (CI: 2%, 5%) under extreme heat. People in urban areas experienced higher mortality risk under extreme cold and heat than those in rural regions. The elderly had the highest RR under both extreme cold and heat. Males experienced greater cold effects than females, whereas the reverse was true with heat effects, particularly among the elderly. Those who were unmarried had higher RR than those married under extreme heat, and the effect remained after controlling for age. The younger population living in the most deprived areas experienced higher cold and heat effects than in less deprived areas. Deaths from respiratory diseases were most sensitive to both cold and heat exposures, although mortality risk for cardiovascular diseases was also heightened, particularly in the elderly. Cold effects were lower in the most recent 15 years, which may be linked to policies and actions in preventing the vulnerable population from cold impacts. No temporal trend was found with the heat effect.

CONCLUSIONS

This study assesses mortality risk associated with extreme temperatures in Scotland and identifies those groups who would benefit most from targeted actions to reduce cold- and heat-related mortalities.

Spatiotemporal mechanism of urban heat island effects on human health—Evidence from Tianjin city of China

The increasingly intensifying global warming and urban heat island (UHIs) are seriously damaging the physical and mental health of urban residents. However, the spatiotemporal evolution of how high temperatures affect human health in megacities remains unclear. Therefore, in this study, with Tianjin during 2006–2020 as an example, and based on data from meteorological stations, Landsat remote sensing images, and point of interest big data, this study applied hot- and cold-spot statistics and remote sensing retrieval in numerical modeling and established an appraisal system to assess how and to what extent UHIs affect resident health. The results showed that the overall influence of UHIs on respiratory and cardiovascular diseases and mental health increased to 373 km2 in area and two levels in intensity; the influence was mainly concentrated in the downtown area, with a rising influence level. Owing to the dual-core structure of the city, the influence was distributed along the main traffic lines in Binhai New District, having a strong influence in the area mainly concentrated in the southeastern part. Many cold spots clustered in the central urban area to cool the thermal environment: the cooled area was 6.5 times larger than the area of intense cooling influence. Our study provides a method for identifying health risks in urban spaces, lays a theoretical foundation to improve the planning of urban green space systems, and offers some decision-making guidance for the planning of healthy cities.

Evaluations of heat action plans for reducing the health impacts of extreme heat: methodological developments (2012-2021) and remaining challenges

The recent report of the Intergovernmental Panel on Climate Change is stark in its warnings about the changing climate, including future increases in the frequency and intensity of extremely hot weather. The well-established impacts of extreme heat on human health have led to widespread implementation of national and city-wide heat plans for mitigating such impacts. Evaluations of the effectiveness of some heat plans have been published, with previous reviews highlighting key methodological challenges. This article reviews methods used since and that address those challenges, so helping to set an agenda for improving evaluations of heat plans in terms of their effectiveness in reducing heat-health impacts. We examined the reviews that identified the methodological challenges and systematically searched the literature to find evaluations that had since been conducted. We found 11 evaluations. Their methods help address the key challenge of identifying study control groups and address other challenges to a limited extent. For future evaluations, we recommend: utilising recent evaluation methodologies, such as difference-in-differences quasi-experimental designs where appropriate; cross-agency working to utilise data on morbidity and confounders; adoption of a proposed universal heat index; and greater publication of evaluations. More evaluations should assess morbidity outcomes and be conducted in low- and middle-income countries. Evaluations of heat plans globally should employ robust methodologies, as demonstrated in existing studies and potentially transferrable from other fields. Publication of such evaluations will advance the field and thus help address some of the health challenges resulting from our changing climate.

Annual Maps of Built-Up Land in Guangdong from 1991 to 2020 Based on Landsat Images, Phenology, Deep Learning Algorithms, and Google Earth Engine

Accurate mapping of built-up land is essential for urbanization monitoring and ecosystem research. At present, remote sensing is one of the primary means used for real-time and accurate surveying and mapping of built-up land, due to the long time series and multi-information advantages of existing remote sensing images and the ability to obtain highly precise year-by-year built-up land maps. In this study, we obtained feature-enhanced data regarding built-up land from Landsat images and phenology-based algorithms and proposed a method that combines the use of the Google Earth Engine (GEE) and deep learning approaches. The Res-UNet++ structural model was improved for built-up land mapping in Guangdong from 1991 to 2020. Experiments show that overall accuracy of built-up land map in the study area in 2020 was 0.99, the kappa coefficient was 0.96, user accuracy of built-up land was 0.98, and producer accuracy was 0.901. The trained model can be applied to other years with good results. The overall accuracy (OA) of the assessment results every five years was above 0.97, and the kappa coefficient was above 0.90. From 1991 to 2020, built-up land in Guangdong has expanded significantly, the area of built-up land has increased by 71%, and the proportion of built-up land has increased by 3.91%. Our findings indicate that the combined approach of GEE and deep learning algorithms can be developed into a large-scale, long time-series of remote sensing classification techniques framework that can be useful for future land-use mapping research.

Health Risk Assessment and Influencing Factors Analysis of High Temperatures on Negative Emotions

The emotional health of urban residents has been seriously threatened by frequent and normalized heat waves. This study constructed the VI-level assessment standard for emotional health risk using data from satellite images, meteorological sites, questionnaire surveys, and statistical yearbooks to assess the effect of high temperatures on negative emotions in Hangzhou. The results showed that the morphological changes of urban high-temperature areas were aggregated from a cross-shape to a large patch shape, then dispersed into cracked patch shapes. Additionally, the health risk of daytime negative emotions peaked at the VI-level from 1984 to 2020, and the influence level of the typical period risk increased by 1–2 levels compared with the daytime. Additionally, driven by urban spatial structure policies, the risk pattern of emotional health expanded outward from a single center into multiple centers. The emotional health risk level rose and then descended in urban centers, and the innovation industries drove the variation tendency of hot spots. Furthermore, high educational background, employment, and couples living together were critical variables that could alleviate the emotional health risk to the middle-aged and elderly population. This study aimed to optimize the urban spatial structure and alleviate residents’ emotional health hazards for healthy urban planning.

Cooling the City? A Scientometric Study on Urban Green and Blue Infrastructure and Climate Change-Induced Public Health Effects

Climate change causes global effects on multiple levels. The anthropogenic input of greenhouse gases increases the atmospheric mean temperature. It furthermore leads to a higher probability of extreme weather events (e.g., heat waves, floods) and thus strongly impacts the habitats of humans, animals, and plants. Against this background, research and innovation activities are increasingly focusing on potential health-related aspects and feasible adaptation and mitigation strategies. Progressing urbanization and demographic change paired with the climate change-induced heat island effect exposes humans living in urban habitats to increasing health risks. By employing scientometric methods, this scoping study provides a systematic bird’s eye view on the epistemic landscapes of climate change, its health-related effects, and possible technological and nature-based interventions and strategies in order to make urban areas climate proof. Based on a literature corpus consisting of 2614 research articles collected in SCOPUS, we applied network-based analysis and visualization techniques to map the different scientific communities, discourses and their interrelations. From a public health perspective, the results demonstrate the range of either direct or indirect health effects of climate change. Furthermore, the results indicate that a public health-related scientific discourse is converging with an urban planning and building science driven discourse oriented towards urban blue and green infrastructure. We conclude that this development might mirror the socio-political demand to tackle emerging climate change-induced challenges by transgressing disciplinary boundaries.

Assessing the Spatial Mapping of Heat Vulnerability under Urban Heat Island (UHI) Effect in the Dhaka Metropolitan Area

The urban heat island (UHI) phenomenon gets intensified in the process of urbanization, which increases the vulnerability of urban dwellers to heatwaves. The UHI-induced vulnerability to heatwaves has increased in Bangladesh during past decades. Thus, this study aims to examine the UHI and vulnerability to heatwaves in the city of Dhaka using a heat vulnerability index (HVI). The HVI is constructed using various demographic, socioeconomic, and environmental risk variables at thana level. Principal component analysis (PCA) was applied to the 26 normalized variables for each of the 41 thanas of Dhaka to prepare the HVI. Result shows that more than 60% of the city is under built-up areas, while vegetation cover and water bodies are in low proportion. Analysis of HVI shows that the very high- and high-risk zones comprise 6 and 11 thanas, while low- and very low-risk zones comprise only 5 and 8 thanas. The correlation of HVI with variables such as exposure (0.62) and sensitivity (0.80) was found to be highly positive, while adaptive capacity had a negative correlation (−0.26) with the HVI. Findings of this study can be utilized in the mitigation of UHI phenomenon and maintaining the thermal comfort of Dhaka.

Warmer summer nocturnal surface air temperatures and cardiovascular disease death risk: a population-based study

BACKGROUND

In recent summers, some populous mid-latitude to high-latitude regions have experienced greater heat intensity, more at night than by day. Such warming has been associated with increased cause-specific adult mortality. Sex-specific and age-specific associations between summer nocturnal surface air temperatures (SAT) and cardiovascular disease (CVD) deaths have yet to be established.

METHODS

A monthly time series analysis (June-July, 2001-2015) was performed on sex-specific CVD deaths in England and Wales of adults aged 60-64 and 65-69 years. Using negative binomial regression with autocorrelative residuals, associations between summer (June-July) nocturnal SAT anomalies (primary exposure) and CVD death rates (outcome) were computed, controlling for key covariates. To explore external validity, similar associations with respect to CVD death in King County, Washington, USA, also were calculated, but only for men aged 60-64 and 65-69 years. Results are reported as incidence rate ratios.

RESULTS

From 2001 to 2015, within these specific cohorts, 39 912 CVD deaths (68.9% men) were recorded in England and Wales and 488 deaths in King County. In England and Wales, after controlling for covariates, a 1°C rise in anomalous summer nocturnal SAT associated significantly with a 3.1% (95% CI 0.3% to 5.9%) increased risk of CVD mortality among men aged 60-64, but not older men or either women age groups. In King County, after controlling for covariates, a 1°C rise associated significantly with a 4.8% (95% CI 1.7% to 8.1%) increased risk of CVD mortality among those <65 years but not older men.

CONCLUSION

In two mid-latitude regions, warmer summer nights are accompanied by an increased risk of death from CVD among men aged 60-64 years.

Impacts of Environmental Insults on Cardiovascular Aging

PURPOSE OF REVIEW

With cardiovascular disease (CVD) being the top cause of deaths worldwide, it is important to ensure healthy cardiovascular aging through enhanced understanding and prevention of adverse health effects exerted by external factors. This review aims to provide an updated understanding of environmental influences on cardiovascular aging, by summarizing epidemiological and mechanistic evidence for the cardiovascular health impact of major environmental stressors, including air pollution, endocrine-disrupting chemicals (EDCs), metals, and climate change.

RECENT FINDINGS

Recent studies generally support positive associations of exposure to multiple chemical environmental stressors (air pollution, EDCs, toxic metals) and extreme temperatures with increased risks of cardiovascular mortality and morbidity in the population. Environmental stressors have also been associated with a number of cardiovascular aging-related subclinical changes including biomarkers in the population, which are supported by evidence from relevant experimental studies. The elderly and patients are the most vulnerable demographic groups to majority environmental stressors. Future studies should account for the totality of individuals' exposome in addition to single chemical pollutants or environmental factors. Specific factors most responsible for the observed health effects related to cardiovascular aging remain to be elucidated.

Impacts of the COVID-19 confinement on air quality, the Land Surface Temperature and the urban heat island in eight cities of Andalusia (Spain)

The COVID-19 outbreak and ensuing global lockdown situation have generated a very negative impact on the world economy, but they have also lent us a unique opportunity to research and better grasp the impacts of human activity on environmental pollution and urban climates. Such studies will be of vital importance for decision-making on measures needed to mitigate the effects of climate change in urban areas, in order to turn them into resilient environments. This study looks at eight cities in the region of Andalusia (southern Spain) to comprehensively assess their environmental quality with parameters (Pm10, So2, No2, Co and O3) obtained from meteorological stations. The aim was to determine how these parameters affect the Land Surface Temperature (LST) and the Surface Urban Heat Island (SUHI), on the basis of Sentinel 3 satellite thermal images. Knowing to what extent improved air quality can reduce the LST and SUHI of cities will be essential in the context of future environmental studies on which to base sustainable decisions. The geographic situation of cities in the Mediterranean Sea basin, highly vulnerable to climate change, and the high pollution rates and high daily temperature variations of these urban areas make them particularly attractive for analyses of this sort. During the confinement period, average reductions of some environmental pollutants were achieved: So2 (-33.5%), Pm10 (-38.3%), No2 (-44.0%) and Co (-26.5%). However, the environmental variable O3 underwent an average growth of 5.9%. The LST showed an average reduction of -4.6 °C (-19.3%), while the SUHI decreased by 1.02 °C (-59.8%). These values exhibit high spatio-temporal variations between day and night, and between inland and coastal cities.

Risk and Resilience: How Is the Health of Older Adults and Immigrant People Living in Canada Impacted by Climate- and Air Pollution-Related Exposures?

BACKGROUND

In the rapidly shifting Canadian climate, an ageing population, and increased migration, a greater understanding of how local climate and air pollution hazards impact older adults and immigrant populations will be necessary for mitigating and adapting to adverse health impacts.

OBJECTIVES

To explore the reported health impacts of climate change and air pollution exposures in older adults and immigrant people living in Canada, identify known factors influencing risk and resilience in these populations and gaps in the literature.

METHODS

We searched for research focused on older adults and immigrants living in Canada, published from 2010 onward, where the primary exposures were related to climate or air pollution. We extracted data on setting, exposures, health outcomes, and other relevant contextual factors.

RESULTS AND DISCUSSION

We identified 52 eligible studies, most focused in Ontario and Quebec. Older people in Canada experience health risks due to climate and air pollution exposures. The extent of the risk depends on multiple factors. We found little information about the climate- and air pollution-related health impacts experienced by immigrant communities.

CONCLUSIONS

Further research about climate- and air pollution-related exposures, health, and which factors promote or reduce resiliency in Canada's older adults and immigrant communities is necessary.

Public attitudes to, and behaviours taken during, hot weather by vulnerable groups: results from a national survey in England

Background

Hot weather leads to increased illness and deaths. The Heatwave Plan for England (HWP) aims to protect the population by raising awareness of the dangers of hot weather, especially for those most vulnerable. Individuals at increased risk to the effects of heat include older adults, particularly 75+, and those with specific chronic conditions, such as diabetes, respiratory and heart conditions. The HWP recommends specific protective actions which relate to five heat-health alert levels (levels 0–4). This study examines the attitudes to hot weather of adults in England, and the protective measures taken during a heatwave.

Methods

As part of a wider evaluation of the implementation and effects of the HWP, a survey (n = 3153) and focus groups, a form of group interview facilitated by a researcher, were carried out after the June 2017 level 3 heat-health alert. Survey respondents were categorised into three groups based on their age and health status: ‘vulnerable’ (aged 75+), ‘potentially vulnerable’ (aged 18–74 in poor health) and ‘not vulnerable’ (rest of the adult population) to hot weather. Multivariable logistic regression models identified factors associated with these groups taking protective measures. In-person group discussion, focused on heat-health, were carried out with 25 people, mostly aged 75 + .

Results

Most vulnerable and potentially vulnerable adults do not consider themselves at risk of hot weather and are unaware of the effectiveness of important protective behaviours. Only one-quarter of (potentially) vulnerable adults reported changing their behaviour as a result of hearing hot weather-related health advice during the level 3 alert period. Focus group findings showed many vulnerable adults were more concerned about the effects of the sun’s ultra-violet radiation on the skin than on the effects of hot temperatures on health.

Conclusions

Current public health messages appear to be insufficient, given the low level of (potentially) vulnerable adults changing their behaviour during hot weather. In the context of increasingly warmer summers in England due to climate change, public health messaging needs to convince (potentially) vulnerable adults of all the risks of hot weather (not just effects of sunlight on the skin) and of the importance of heat protective measures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11668-x.

A Qualitative Study on Concerns, Needs, and Expectations of Hospital Patients Related to Climate Change: Arguments for a Patient-Centered Adaptation

This study explores the concerns, needs, and expectations of inpatients with the goal to develop a patient-centered climate change adaptation agenda for hospitals. Statements of patients from geriatrics, internal medicine, psychiatry, and surgery (N = 25) of a German tertiary care hospital were analyzed using semi-structured interviews and the framework method. Areas of future adaptation were elaborated in joint discussions with transdisciplinary experts. Concerns included the foresight of severe health problems. The requested adaptations comprised the change to a patient-centered care, infrastructural improvements including air conditioning, and adjustments of the workflows. Guidelines for the behavior of patients and medical services appropriate for the climatic conditions were demanded. The patient-centered agenda for adaptation includes the steps of partnering with patients, reinforcing heat mitigation, better education for patients and medical staff, and adjusting work processes. This is the first study demonstrating that hospital patients are gravely concerned and expect adjustments according to climate change. Since heat is seen as a major risk by interviewees, the fast implementation of published recommendations is crucial. By synthesizing inpatients’ expectations with scientific recommendations, we encourage patient-centered climate change adaptation. This can be the start for further collaboration with patients to create climate change resilient hospitals.

Born in winter or spring more susceptible to all-cause and cardiovascular disease death in rural areas of China: results from a 11.9-year follow-up study

There has been no evidence on the effects of birth season and birth month on mortality in China. We aimed to explore the association between birth season, birth month and all-cause and cardiovascular disease (CVD) death. A population-based sample of 21,338 Chinese rural participants aged ≥35 years at baseline was included in our analysis. Age and multivariable adjusted Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the relationship between astronomical birth season (autumn as the reference), birth month (November as the reference), and all-cause and CVD mortality. During a median follow-up period of 11.9 years, 2,207 people died from all-cause and 1,214 people were attributed to CVD death. In multivariable adjusted analyses, for all-cause death, spring and winter had HRs (95% CIs) of 1.134 (1.005–1.280) and 1.162 (1.038–1.301), respectively; January, March, May, and August had HRs (95% CIs) of 1.249 (1.027–1.518), 1.234 (1.008–1.512), 1.276 (1.037–1.571), and 1.232 (1.003–1.513), respectively. For CVD death, spring and winter with HRs (95% CIs) of mortality were 1.232 (1.048–1.449) and 1.174 (1.007–1.369), respectively; March with HR (95% CI) of mortality were 1.343 (1.030–1.750) (all P < 0.05). Our study indicated that people born in the winter or spring were significantly associated with all-cause and cardiovascular disease mortality in rural areas of China.

Excess Mortality in England during the 2019 Summer Heatwaves

There is increasing evidence that rising temperatures and heatwaves in the United Kingdom are associated with an increase in heat-related mortality. However, the Public Health England (PHE) Heatwave mortality monitoring reports, which use provisional death registrations to estimate heat-related mortality in England during heatwaves, have not yet been evaluated. This study aims to retrospectively quantify the impact of heatwaves on mortality during the 2019 summer period using daily death occurrences. Second, using the same method, it quantifies the heat-related mortality for the 2018 and 2017 heatwave periods. Last, it compares the results to the estimated excess deaths for the same period in the PHE Heatwave mortality monitoring reports. The number of cumulative excess deaths during the summer 2019 heatwaves were minimal (161) and were substantially lower than during the summer 2018 heatwaves (1700 deaths) and summer 2017 heatwaves (1489 deaths). All findings were at variance with the PHE Heatwave mortality monitoring reports which estimated cumulative excess deaths to be 892, 863 and 778 during the heatwave periods of 2019, 2018 and 2017, respectively. Issues are identified in the use of provisional death registrations for mortality monitoring and the reduced reliability of the Office for National Statistics (ONS) daily death occurrences database before 2019. These findings may identify more reliable ways to monitor heat mortality during heatwaves in the future.

Years of life lost and mortality due to heat and cold in the three largest English cities

There is a well-established relationship between temperature and mortality, with older individuals being most at risk in high-income settings. This raises the question of the degree to which lives are being shortened by exposure to heat or cold. Years of life lost (YLL) take into account population life expectancy and age at which mortality occurs. However, YLL are rarely used as an outcome-metric in studies of temperature-related mortality. This represents an important gap in knowledge; to better comprehend potential impacts of temperature in the context of climate change and an ageing population, it is important to understand the relationship between temperature and YLL, and also whether the risks of temperature related mortality and YLL have changed over recent years. Gridded temperature data derived from observations, and mortality data were provided by the UK Met Office and the Office for National Statistics (ONS), respectively. We derived YLL for each death using sex-specific yearly life expectancy from ONS English-national lifetables. We undertook an ecological time-series regression analysis, using a distributed-lag double-threshold model, to estimate the relationship between daily mean temperature and daily YLL and mortality between 1996 and 2013 in Greater London, the West Midlands including Birmingham, and Greater Manchester. Temperature-thresholds, as determined by model best fit, were set at the 91st (for heat-effects) and 35th (for cold-effects) percentiles of the mean temperature distribution. Secondly, we analysed whether there had been any changes in heat and cold related risk of YLL and mortality over time. Heat-effects (lag 0-2 days) were greatest in London, where for each 1 °C above the heat-threshold the risk of mortality increased by 3.9% (CI 3.5%, 4.3%) and YLL increased by 3.0% (2.5%, 3.5%). Between 1996 and 2013, the proportion of total deaths and YLL attributable to heat in London were 0.50% and 0.40% respectively. Cold-effects (lag 0-27 days) were greatest in the West Midlands, where for each 1 °C below the cold-threshold, risk of mortality increased by 3.1% (2.4%, 3.7%) and YLL also increased by 3.1% (2.2%, 3.9%). The proportion of deaths and YLL attributable to cold in the West Midlands were 3.3% and 3.2% respectively. We found no evidence of decreasing susceptibility to heat and cold over time. The addition of life expectancy information into calculations of temperature-related risk and mortality burdens for English cities is novel. We demonstrate that although older individuals are at greatest risk of temperature-related mortality, heat and cold still make a significant contribution to the YLL due to premature death.

Mitigating heat-related mortality risk in Shanghai, China: system dynamics modeling simulations

Numerous studies in epidemiology, meteorology, and climate change research have demonstrated a significant association between abnormal ambient temperature and mortality. However, there is a shortage of research attention to a systematic assessment of potential mitigation measures which could effectively reduce the heat-related morbidity and mortality risks. This study first illustrates a conceptualization of a systems analysis version of urban framework for climate service (UFCS). It then constructs a system dynamics (SD) model for the UFCS and employs this model to quantify the impacts of heat waves on public health system in Shanghai and to evaluate the performances of two mitigation measures in the context of a real heat wave event in July 2013 in the city. Simulation results show that in comparison with the baseline without mitigation measures, if the hospital system could prepare 20% of beds available for emergency response to heat waves once receiving the warning in advance, the number of daily deaths could be reduced by 40-60 (15.8-19.5%) on the 2 days of day 7 and day 8; if increasing the minimum living allowance of 790 RMB/month in 2013 by 20%, the number of daily deaths could be reduced by 50-70 (17.7-21.9%) on the 2 days of day 8 and day 12. This tool can help policy makers systematically evaluate adaptation and mitigation options based on performance assessment, thus strengthening urban resilience to changing climate.

Comparison of Respiratory and Ischemic Heart Mortalities and their Relationship to the Thermal Environment

Chronic respiratory and ischemic heart diseases are globally important parts of total mortality. This study focuses on the occurrence of mortality due to these disease groups in Germany and possible effects of the thermal environment. A retrospective analysis on the mortality rates of chronic lower respiratory diseases (CLRD) and ischemic heart diseases (IHD) at the regional level in Germany for the period 2001–2015 was done in combination with meteorological observations from the network of the German Meteorological Service. In order to control the mortality data for long-term and seasonal trends, a 365-day Gaussian low-pass filter with a filter response function was applied. The thermal environment was analysed using 2 m air temperature (Ta) and the human biometeorological index Perceived Temperature (PT). The relationship of the Relative Risk (RR) of mortality to the thermal environment is displayed as an exposure–response curve, with threshold values at which RR increases significantly towards higher and lower temperature values. CLRD mortality increases above 17.6 °C, at approximately 4.4%/°C (CI: ± 0.3). The increase of IHD mortality above the threshold of 18.8 °C is less steep, at 3.5%/°C (CI: ± 0.2). During hot periods, CLRD mortality increases by 19.9%, which is twice as much as IHD mortality, with an increase of 9.8%. However, cold days and cold periods affect IHD slightly more than CLRD. The results highlight the concerns of CLRD patients during hot days as well as heat waves. This could lead to better precautions being taken for respiratory patients, which are already established for cardiac patients in Germany.

Spatiotemporal Variation of Urban Heat Islands for Implementing Nature-Based Solutions: A Case Study of Kurunegala, Sri Lanka

Changes in the urban landscape resulting from rapid urbanisation and climate change have the potential to increase land surface temperature (LST) and the incidence of the urban heat island (UHI). An increase in urban heat directly affects urban livelihoods and systems. This study investigated the spatiotemporal variation of the UHI in the Kurunegala urban area (KUA) of North-Western Province, Sri Lanka. The KUA is one of the most intensively developing economic and administrative capitals in Sri Lanka with an urban system that is facing climate vulnerabilities and challenges of extreme heat conditions. We examined the UHI formation for the period 1996–2019 and its impact on the urban-systems by exploring nature-based solutions (NBS). This study used annual median temperatures based on Landsat data from 1996 to 2019 using the Google Earth Engine (GEE). Various geospatial approaches, including spectral index-based land use/cover mapping (1996, 2009 and 2019), urban-rural gradient zones, UHI profile, statistics and grid-based analysis, were used to analyse the data. The results revealed that the mean LST increased by 5.5 °C between 1996 and 2019 mainly associated with the expansion pattern of impervious surfaces. The mean LST had a positive correlation with impervious surfaces and a negative correlation with the green spaces in all the three time-points. Impacts due to climate change, including positive temperature and negative rainfall anomalies, contributed to the increase in LST. The study recommends interactively applying NBS to addressing the UHI impacts with effective mitigation and adaptation measures for urban sustainability.

Comparison of land surface and air temperatures for quantifying summer and winter urban heat island in a snow climate city

The urban heat island (UHI) effect is an increasingly consequential problem that confronts cities. The accurate characterization and quantification of UHI are crucial for sustainable urban development. Few UHI studies, however, compare data source, spatio-temporal variations, and indicators for the same city in parallel. This study uses Changchun, a snow climate city in China, as an example and compares five different indicators of the UHI based on land surface temperature (LST) derived from Landsat 8 TIRS and hourly air temperature (AT) collected from 41 meteorological weather stations to conduct a more comprehensive comparative study of the UHI. The results show the following. (1) The relationships between LST and AT are all statistically significant, and the surface urban heat island (SUHI) intensity characterized by the LST is considerably stronger than that of AT both in summer and winter. (2) The SUHI intensity is significantly stronger in summer (6.83 °C) than in winter (1.55 °C) based on the morning LST, whereas the UHI intensity (0.27 °C in summer and 0.40 °C in winter) that is simultaneously quantified by the AT has an opposite result. The mean whole-day and daytime UHI intensity difference, which is quantified hourly by the AT between summer and winter, is not significant. The difference between nighttime and daytime UHI intensities is evident in both summer (1.26 °C) and winter (0.76 °C). Additionally, the high temperatures for both LST and AT have a more concentrated distribution in winter than in summer. (3) The values of UHI/SUHI intensity considerably vary based on different indicators. The different choices among land covers to represent "urban" and "rural" areas would significantly affect the values of UHI/SUHI intensity. The selection of appropriate indicators and data sources to quantify the UHI remains a problem that has to be resolved in future studies.

Impact of Air Conditioning Systems on the Outdoor Thermal Environment during Summer in Berlin, Germany

This study investigates the effect of anthropogenic heat emissions from air conditioning systems (AC) on air temperature and AC energy consumption in Berlin, Germany. We conduct simulations applying the model system CCLM/DCEP-BEM, a coupled system of the mesoscale climate model COSMO-CLM (CCLM) and the urban Double Canyon Effect Parameterization scheme with a building energy model (DCEP-BEM), for a summer period of 2018. The DCEP-BEM model is designed to explicitly compute the anthropogenic heat emissions from urban buildings and the heat flux transfer between buildings and the atmosphere. We investigate two locations where the AC outdoor units are installed: either on the wall of a building (VerAC) or on the rooftop of a building (HorAC). AC waste heat emissions considerably increase the near-surface air temperature. Compared to a reference scenario without AC systems, the VerAC scenario with a target indoor temperature of 22 ∘C results in a temperature increase of up to 0.6K. The increase is more pronounced during the night and for urban areas. The effect of HorAC on air temperature is overall smaller than in VerAC. With the target indoor temperature of 22 ∘C, an urban site’s daily average AC energy consumption per floor area of a room is 9.1W m2, which is 35% more than that of a suburban site. This energy-saving results from the urban heat island effect and different building parameters between both sits. The maximum AC energy consumption occurs in the afternoon. When the target indoor temperature rises, the AC energy consumption decreases at a rate of about 16% per 2 K change in indoor temperature. The nighttime near-surface temperature in VerAC scenarios shows a declining trend (0.06K per 2 K change) with increasing target indoor temperature. This feature is not obvious in HorAC scenarios which further confirms that HorAC has a smaller impact on near-surface air temperature.

Residential green space, air pollution, socioeconomic deprivation and cardiovascular medication sales in Belgium: A nationwide ecological study

Green space may improve cardiovascular (CV) health, for example by promoting physical activity and by reducing air pollution, noise and heat. Socioeconomic and environmental factors may modify the health effects of green space. We examined the association between residential green space and reimbursed CV medication sales in Belgium between 2006 and 2014, adjusting for socioeconomic deprivation and air pollution. We analyzed data for 11,575 census tracts using structural equation models for the entire country and for the administrative regions. Latent variables for green space, air pollution and socioeconomic deprivation were used as predictors of CV medication sales and were estimated from the number of patches of forest, census tract relative forest cover and relative forest cover within a 600 m buffer around the census tract; annual mean concentrations of PM_2.5, BC and NO₂; and percentages of inhabitants that were foreign-born from lower- and mid-income countries, unemployed or had no higher education. A direct association between socioeconomic deprivation and CV medication sales [parameter estimate (95% CI): 0.26 (0.25; 0.28)] and inverse associations between CV medication sales and green space [-0.71 (-0.80; -0.61)] and air pollution [-1.62 (-1.69; -0.61)] were observed. In the regional models, the association between green space and CV medication sales was stronger in the region with relatively low green space cover (Flemish Region, standardized estimate -0.16) than in the region with high green space cover (Walloon Region, -0.10). In the highly urbanized Brussels Capital Region the association tended towards the null. In all regions, the associations between CV medication sales and socioeconomic deprivation were direct and more prominent. Our results suggest that there may be an inverse association between green space and CV medication sales, but socioeconomic deprivation was always the strongest predictor of CV medication sales.

Heat-health vulnerability in temperate climates: lessons and response options from Ireland

Background

In Ireland, rising temperatures remains the climate projection that national climate scientists associate with the highest degree of confidence. However, the health challenge of heat has been largely absent from Ireland’s public health sector. This is epitomised by the lack of a comprehensive public health-focused heat-health action plan or country-specific codes of practice for heat-health when working outdoors. Our objective is to highlight the anticipated heat-health challenges in Ireland, and other temperate regions, through analysing vulnerable groups and systems, reinforcing the need to respond.

Methods

A scoping literature review was conducted to determine how heat affects health of the vulnerable in temperate climatic regions, with a focus on Ireland. Additionally, national Google Trends data was coarsely analysed to determine whether heat is a growing societal concern.

Results and discussion

The heat-vulnerable include: older people; chronically ill; infants, pregnant women, children; outdoor workers; socio-economically disadvantaged; urban dwellers; food systems and the health sector. Google Trends data suggest an increase in heat-related health searches over time, demonstrating rising levels of concern to temperature increases, reinforcing a gap in national policy associated with communication of, and response to, the heat-health challenge. Specific, actionable recommendations for adaptation and mitigation strategies are proposed.

Conclusion

Heat poses a public and occupational health challenge, receiving limited attention in Ireland. Lack of a co-ordinated effort, places vulnerable populations at risk. Our recommendations, with reference to vulnerable groups and acknowledging the multi-sectoral nature of heat-health and climate change, advocate for the adoption of a “health and climate change in all policies” approach and the development of a public health-focused heat-health action plan.

Weather patterns and all-cause mortality in England, UK

Cold- and heat-related mortality poses significant public health concerns worldwide. Although there are numerous studies dealing with the association between extreme ambient temperature and mortality, only a small number adopt a synoptic climatological approach in order to understand the nature of weather systems that precipitate increases in cold- or heat-related mortality. In this paper, the Lamb Weather Type synoptic classification is used to examine the relationship between daily mortality and weather patterns across nine regions of England. Analysis results revealed that the population in England is more susceptible to cold weather. Furthermore, it was found that the Easterly weather types are the most hazardous for public health all-year-long; however, during the cold period, the results are more evident and spatially homogenous. Nevertheless, it is noteworthy that the most dangerous weather conditions are not always associated with extreme (high or low) temperatures, a finding which points to the complexity of weather-related health effects and highlights the importance of a synoptic climatological approach in elucidating the relationship between temperature and mortality.

Heatwave Events and Mortality Outcomes in Memphis, Tennessee: Testing Effect Modification by Socioeconomic Status and Urbanicity

Heatwave studies typically estimate heat-related mortality and morbidity risks at the city level; few have addressed the heterogeneous risks by socioeconomic status (SES) and location within a city. This study aimed to examine the impacts of heatwaves on mortality outcomes in Memphis, Tennessee, a Mid-South metropolitan area top-ranked in morbidity and poverty rates, and to investigate the effects of SES and urbanicity. Mortality data were retrieved from the death records in 2008-2017, and temperature data from the Applied Climate Information System. Heatwave days were defined based on four temperature metrics. Heatwave effects on daily total-cause, cardiovascular, and respiratory mortality were evaluated using Poisson regression, accounting for temporal trends, sociodemographic factors, urbanicity, and air pollution. We found higher cardiovascular mortality risk (cumulative RR (relative risk) = 1.25, 95% CI (confidence interval): 1.01-1.55) in heatwave days defined as those with maximum daily temperature >95th percentile for more than two consecutive days. The effects of heatwaves on mortality did not differ by SES, race, or urbanicity. The findings of this study provided evidence to support future heatwave planning and studies of heatwave and health impacts at a coarser geographic resolution.

Heat Health Prevention Measures and Adaptation in Older Populations-A Systematic Review

The population of older people is increasing at a rapid rate, with those 80 years and older set to triple by 2050. This systematic review aimed to examine older people’s perceptions and behaviours against existing heatwaves prevention measures and systematically categorize and analyse those measures using the Ottawa charter for health promotion framework. Peer-reviewed published literature between 22nd September 2006 and 24th April 2018 was retrieved, according to the PRISMA guidelines, from five different databases. Eighteen articles were finally included. There is a lack of published studies from developing countries. Results were categorized and analysed using the Ottawa charter five action areas. Mitigation strategies from current heat action plans are discussed and gaps are highlighted. A lack of systematic evaluation of heat action plans efficacy was identified. Older people are not demonstrating all recommended preventative measures during heatwaves. Support personnel and health professionals are not being pro-active enough in facilitating prevention of adverse effects from heatwaves. Governments are beginning to implement policy changes, but other recommended support measures outlined in the Ottawa charter are still lacking, and hence require further action. Linkage between specific components of heat action plans and outcomes cannot be ascertained; therefore, more systematic evaluation is needed.

Future Heat Waves in Different European Capitals Based on Climate Change Indicators

Changes in the frequency and intensity of heat waves have shown substantial negative impacts on public health. At the same time, climate change towards increasing air temperatures throughout Europe will foster such extreme events, leading to the population being more exposed to them and societies becoming more vulnerable. Based on two climate change scenarios (Representative Concentration Pathway 4.5 and 8.5) we analysed the frequency and intensity of heat waves for three capital cities in Europe representing a North-South transect (London, Luxembourg, Rome). We used indices proposed by the Expert Team on Sector-Specific Climate Indices of the World Meteorological Organization to analyze the number of heat waves, the number of days that contribute to heat waves, the length of the longest heat waves, as well as the mean temperature during heat waves. The threshold for the definition of heat waves is calculated based on a reference period of 30 years for each of the three cities, allowing for a direct comparison of the projected changes between the cities. Changes in the projected air temperature between a reference period (1971-2000) and three future periods (2001-2030 near future, 2031-2060 middle future, and 2061-2090 far future) are statistically significant for all three cities and both emission scenarios. Considerable similarities could be identified for the different heat wave indices. This directly affects the risk of the exposed population and might also negatively influence food security and water supply.

Heat-health action plans in Europe: Challenges ahead and how to tackle them

High temperatures have periodically affected large areas in Europe and urban settings. In particular, the deadly 2003 summer heat waves precipitated a multitude of national and subnational health prevention and research efforts. Building on these and other international experiences the WHO Regional Office for Europe developed and published in 2008 a comprehensive framework for prevention, the heat-health action plans (HHAPs). This provided a blueprint used by several national and subnational authorities to design their prevention efforts. A decade after the publication of the WHO guidance, a wealth of new evidence and acquired implementation experience has emerged around HHAP effectiveness; heat exposure; acclimatization and adaptation; heat-health governance and stakeholder involvement; and the role of urban design and greening interventions in prevention. This evidence and experience can guide the strategies to tackle current and upcoming challenges in protecting health from heat under a warming climate.

The Use of a Quasi-Experimental Study on the Mortality Effect of a Heat Wave Warning System in Korea

Many cities and countries have implemented heat wave warning systems to combat the health effects of extreme heat. Little is known about whether these systems actually reduce heat-related morbidity and mortality. We examined the effectiveness of heat wave alerts and health plans in reducing the mortality risk of heat waves in Korea by utilizing the discrepancy between the alerts and the monitored temperature. A difference-in-differences analysis combined with propensity score weighting was used. Mortality, weather monitoring, and heat wave alert announcement data were collected for 7 major cities during 2009–2014. Results showed evidence of risk reduction among people aged 19–64 without education (−0.144 deaths/1,000,000 people, 95% CI: −0.227, −0.061) and children aged 0–19 (−0.555 deaths/1,000,000 people, 95% CI: −0.993, −0.117). Decreased cardiovascular and respiratory mortality was found in several subgroups including single persons, widowed people, blue-collar workers, people with no education or the highest level of education (university or higher). No evidence was found for decreased all-cause mortality in the population (1.687 deaths/1,000,000 people per day; 95% CI: 1.118, 2.255). In conclusion, heat wave alerts may reduce mortality for several causes and subpopulations of age and socio-economic status. Further work needs to examine the pathways through which the alerts impact subpopulations differently.

Potential benefits of cool roofs in reducing heat-related mortality during heatwaves in a European city

Hot weather can exacerbate health conditions such as cardiovascular and respiratory diseases, and lead to heat stroke and death. In built up areas, temperatures are commonly observed to be higher than those in surrounding rural areas, due to the Urban Heat Island (UHI) effect. Climate change and increasing urbanisation mean that future populations are likely to be at increased risk of overheating in cities, although building and city scale interventions have the potential to reduce this risk. We use a regional weather model to assess the potential effect of one type of urban intervention - reflective 'cool' roofs - to reduce local ambient temperatures, and the subsequent impact on heat-related mortality in the West Midlands, UK, with analysis undertaken for the summer of 2006, as well as two shorter heatwave periods in 2006 and 2003. We show that over a summer season, the population-weighted UHI intensity (the difference between simulated urban and rural temperature) was 1.1 °C on average, but 1.8 °C when including only night times, and reached a maximum of 9 °C in the West Midlands. Our results suggest that the UHI contributes up to 40% of heat related mortality over the summer period and that cool roofs implemented across the whole city could potentially offset 18% of seasonal heat-related mortality associated with the UHI (corresponding to 7% of total heat-related mortality). For heatwave periods, our modelling suggests that cool roofs could reduce city centre daytime 2 m air temperature by 0.5 °C on average, and up to a maximum of ~3 °C. Cool roofs reduced average UHI intensity by ~23%, and reduced heat related mortality associated with the UHI by ~25% during a heatwave. Cool roofs were most effective at reducing peak temperatures during the daytime, and therefore have the potential to limit dangerous extreme temperatures during heatwaves. Temperature reductions were dependent on the category of buildings where cool roofs were applied; targeting only commercial and industrial type buildings contributed more than half of the reduction for heatwave periods. Our modelling suggested that modifying half of all industrial/commercial urban buildings could have the same impact as modifying all high-intensity residential buildings in the West Midlands.

Greening of the Heart and Mind

See Article by Wang et al

Impact of heatwaves on daily outpatient visits of respiratory disease: A time-stratified case-crossover study

OBJECTIVES

This study aims to estimate the impact of heatwaves from July 2010 to October 2012 on daily outpatient visits for respiratory disease (RD) in Cangnan, China and identify vulnerable populations.

METHODS

The definition of heatwave was a period at least 3 consecutive days with maximum temperature exceeding 35 °C in this study. A time-stratified case-crossover design was conducted to examine the relationship between heatwaves and outpatient visits for RD. Patient data for the period from 2010 to 2012 were collected from the Third People's Hospital of Cangnan and daily meteorological data for the same period were collected from the China Meteorological Data Service Center. Data regarding the air pollution index (API), a composite indicator of air pollution, were collected from the Data Center of the Chinese Ministry of Environmental Protection. RD were identified based on the 10th revision International Classification of Diseases (ICD-10) codes (J00-J99). A conditional Poisson regression model was applied to examine the heatwave-RD association using the Relative Risk (RR) while adjusting for meteorological and air pollution factors including temperature, rainfall, wind speed, pressure, humidity, sunshine hours and API.

RESULTS

During the study period, 4 heatwaves occurred and a total of 1732 outpatient visits for RD were reported. Heatwaves increased the frequency of RD outpatient visits and the highest RR of total RD was 1.155% and 95% Confidence Intervals (95% CI) was 1.084-1.232 at Lag 0. For subcategories, heatwaves increased the risk of infectious RD (Lag 0: RR =1.182, 95% CI: 1.106-1.263) and decreased the risk of non-infectious RD ((Lag 6: RR =0.750, 95% CI: 0.568-0.990). Moreover, heatwaves showed adverse effects on acute upper respiratory infection (Lag 0: RR =1.306, 95% CI: 1.177-1.450). The RR of outpatient visits for RD was statistically significant in females (Lag 0: RR =1.161, 95% CI: 1.046-1.298), males (Lag 4: RR =1.161, 95% CI: 1.096-1.261), young people aged 4-17 years (Lag 0: RR =1.741, 95% CI: 1.524-1.990) and elders aged 65 years or older (Lag 5: RR =1.412, 95% CI: 1.111-1.794) during heatwaves.

CONCLUSIONS

Heatwaves had a significant harmful impact on daily outpatient visits for RD in Cangnan, especially for vulnerable population identified. These results can be used not only to strengthen the health education and protection of these vulnerable populations, but also to assist relevant organizations with developing intervention programmes and improving disease prevention and community care.

Mortality burden attributable to heatwaves in Thailand: A systematic assessment incorporating evidence-based lag structure

BACKGROUND

Available information on the acute and cumulative effects of heatwaves on cause-specific mortality in Thailand is scarce.

OBJECTIVES

To quantify the acute and cumulative effects of heatwaves on mortality in Thailand, and assess heatwave-related mortality burden.

METHODS

Thirty heatwave definitions were used and categorized into three groups: low intensity heatwaves (HW_low), middle intensity heatwaves (HW_middle), and high intensity heatwaves (HW_high). Time-series analyses were conducted to examine the acute and cumulative effects of HW_low, HW_middle, and HW_high on total and cause-specific mortality in 60 provinces of Thailand, incorporating an optimal lag for each cause and each province. Random-effects meta-analyses were performed to pool provincial estimates to national estimates for both acute and cumulative effects. Meta-regressions were conducted to identify the possible factors contributing to the spatial heterogeneity of heatwave vulnerability.

RESULTS

The cumulative effects of HW_low and HW_middle on total and cause-specific mortality were greater than HW_high. Both acute and cumulative effects of HW_low, HW_middle and HW_high on neoplasms and certain infectious and parasitic diseases were among the highest across all death causes. Effects of heatwaves on deaths from endocrine, nutritional and metabolic diseases appeared to be longer-lasting, and effects of heatwaves on deaths from ischaemic heart diseases and pneumonia occurred more rapidly. Northern and Central Thailand were the regions vulnerable to heatwaves, and proportion of elderly population was the major driver behind the spatial heterogeneity of heatwave vulnerability.

CONCLUSIONS

More attention needs to be paid to mild heatwaves. Future heatwave-related mortality burden due to neoplasms and infectious diseases in Thailand may increase as climate change continues.

The added effects of heatwaves on cause-specific mortality: A nationwide analysis in 272 Chinese cities

BACKGROUND

The evidence was limited and inconclusive about the added effects of heatwaves, especially in developing countries.

OBJECTIVE

To evaluate the added effects of heatwaves on cause-specific mortality in China.

METHODS

We designed a nationwide time-series analysis based on daily data from 272 main Chinese cities to from 2013 to 2015. We adopted 12 definitions by combining 4 heat thresholds (90th, 92.5th, 95th, 97.5th percentile of city-specific daily mean temperature) and duration of ≥2, 3 and 4 days. We applied overdispersed generalized additive models with distributed lag models to estimate the city-specific cumulative effects of heatwaves over lags of 0-10 days after controlling for daily temperature. We then, used a meta-regression model to pool the effect estimates at national and regional levels.

RESULTS

Heatwaves could significantly increase risk for mortality from total and cardiopulmonary diseases, including coronary heart disease, ischemic stroke (rather than hemorrhagic stroke) and chronic obstructive pulmonary disease. The effects increased with higher thresholds, but were not appreciably influenced by the duration of heat. The risks generally occurred immediately and lasted for 3 to 5 days. The risks were much larger in the temperate continental zone and the temperate monsoon zones than in the subtropical monsoon zone where there was an evident mortality displacement. The elderly, females and less-educated people were more vulnerable.

CONCLUSIONS

This analysis provided ample evidence for the added mortality risk associated with heatwaves, which had important implications for designing heatwave-warning systems and predicting the disease burden of future heatwaves.

Spatial variation of heat-related morbidity: A hierarchical Bayesian analysis in multiple districts of the Mekong Delta Region

This study examined spatial variability of heat-related morbidity in multiple districts of the Mekong Delta Region (MDR), Vietnam. It was conducted in 132 district/cities of the MDR. We used a series of hierarchical Bayesian models to examine the region-wide and district-specific association between temperatures and hospitalizations during the period of 2010-2013. The potential effects of seasonality, long-term trends, day of the week and holidays were controlled in the models. We also examined influences of socio-demographic factors on the temperature-hospitalization relationship. The results indicate that an increase of 5 °C in average temperature was associated with a 6.1% increase (95%CI: 5.9, 6.2) in region-wide hospital admissions. However, the district-level risks ranged from a 55.2% decrease {95%CI: (-54), (-56)} to a 24.4% increase (24.3-24.6) in admissions per 5 °C increase in average temperature. This reflects the heterogeneous magnitudes of temperature-hospitalization risk across districts. The results also indicate that temperature-hospitalization risk increased by 1.3% (95%CI: 1.2-1.4), for each increase of 1000 persons/km² in population density, 2.1% (95%CI: 2.04-2.11) for each 1% increase in percent of females, and 2.7% (95%CI: 2.6-2.8) for each 1% increase in percent of pre-school students. In contrast, the temperature-related hospitalization risk decreased up to 6.8% {(95%CI: (-6.6)-(-6.9)} for each 1% increase in rural population. Public health intervention measures for both short-term and long-term effects of heat-related health risk should be developed with consideration of the use of city/district scale for the factors rather than the province scale. The province scale of factors does not accurately represent the variability of health risk due to exposure to high temperatures.

Health impacts of climate change and health and social inequalities in the UK

This article examines how social and health inequalities shape the health impacts of climate change in the UK, and what the implications are for climate change adaptation and health care provision. The evidence generated by the other articles of the special issue were interpreted using social justice reasoning in light of additional literature, to draw out the key implications of health and social inequalities for health outcomes of climate change. Exposure to heat and cold, air pollution, pollen, food safety risks, disruptions to access to and functioning of health services and facilities, emerging infections and flooding are examined as the key impacts of climate change influencing health outcomes. Age, pre-existing medical conditions and social deprivation are found to be the key (but not only) factors that make people vulnerable and to experience more adverse health outcomes related to climate change impacts. In the future, climate change, aging population and decreasing public spending on health and social care may aggravate inequality of health outcomes related to climate change. Health education and public preparedness measures that take into account differential exposure, sensitivity and adaptive capacity of different groups help address health and social inequalities to do with climate change. Adaptation strategies based on individual preparedness, action and behaviour change may aggravate health and social inequalities due to their selective uptake, unless they are coupled with broad public information campaigns and financial support for undertaking adaptive measures.