Cold-related mortality vs heat-related mortality in a changing climate: A case study in Vilnius (Lithuania).

Direct health effects of extreme temperatures are a significant environmental health problem in Lithuania, and could worsen further under climate change. This paper attempts to describe the change in environmental temperature conditions that the urban population of Vilnius could experience under climate change, and the effects such change could have on excess heat-related and cold-related mortality in two future periods within the 21st century. We modelled the urban climate of Vilnius for the summer and winter seasons during a sample period (2009-2015) and projected summertime and wintertime daily temperatures for two prospective periods, one in the near (2030-2045) and one in the far future (2085-2100), under the Representative Concentration Pathway (RCP) 8.5. We then analysed the historical relationship between temperature and mortality for the period 2009-2015, and estimated the projected mortality in the near future and far future periods under a changing climate and population, assuming alternatively no acclimatisation and acclimatisation to heat and cold based on a constant-percentile threshold temperature. During the sample period 2009-2015 in summertime we observed an increase in daily mortality from a maximum daily temperature of 30 °C (the 96th percentile of the series), with an average of around 7 deaths per year. Under a no acclimatisation scenario, annual average heat-related mortality would rise to 24 deaths/year (95% CI: 8.4-38.4) in the near future and to 46 deaths/year (95% CI: 16.4-74.4) in the far future. Under a heat acclimatisation scenario, mortality would not increase significantly in the near or in the far future. Regarding wintertime cold-related mortality in the sample period 2009-2015, we observed increased mortality on days on which the minimum daily temperature fell below - 12 °C (the 7th percentile of the series), with an average of around 10 deaths a year. Keeping the threshold temperature constant, annual average cold-related mortality would decrease markedly in the near future, to 5 deaths/year (95% CI: 0.8-7.9) and even more in the far future, down to 0.44 deaths/year (95% C: 0.1-0.8). Assuming a "middle ground" between the acclimatisation and non-acclimatisation scenarios, the decrease in cold-related mortality will not compensate the increase in heat-related mortality. Thermal extremes, both heat and cold, constitute a serious public health threat in Vilnius, and in a changing climate the decrease in mortality attributable to cold will not compensate for the increase in mortality attributable to heat. Study results reinforce the notion that public health prevention against thermal extremes should be designed as a dynamic, adaptive process from the inception.

Martinez GS ，Diaz J ，Hooyberghs H ，Lauwaet D ，De Ridder K ，Linares C ，Carmona R ，Ortiz C ，Kendrovski V ，Adamonyte D ... -  《-》

Heat and health in Antwerp under climate change: Projected impacts and implications for prevention.

Excessive summer heat is a serious environmental health problem in several European cities. Heat-related mortality and morbidity is likely to increase under climate change scenarios without adequate prevention based on locally relevant evidence. We modelled the urban climate of Antwerp for the summer season during the period 1986-2015, and projected summer daily temperatures for two periods, one in the near (2026-2045) and one in the far future (2081-2100), under the Representative Concentration Pathway (RCP) 8.5. We then analysed the relationship between temperature and mortality, as well as with hospital admissions for the period 2009-2013, and estimated the projected mortality in the near future and far future periods under changing climate and population, assuming alternatively no acclimatization and acclimatization based on a constant threshold percentile temperature. During the sample period 2009-2013 we observed an increase in daily mortality from a maximum daily temperature of 26°C, or the 89th percentile of the maximum daily temperature series. The annual average heat-related mortality in this period was 13.4 persons (95% CI: 3.8-23.4). No effect of heat was observed in the case of hospital admissions due to cardiorespiratory causes. Under a no acclimatization scenario, annual average heat-related mortality is multiplied by a factor of 1.7 in the near future (24.1deaths/year CI 95%: 6.78-41.94) and by a factor of 4.5 in the far future (60.38deaths/year CI 95%: 17.00-105.11). Under a heat acclimatization scenario, mortality does not increase significantly in the near or in the far future. These results highlight the importance of a long-term perspective in the public health prevention of heat exposure, particularly in the context of a changing climate, and the calibration of existing prevention activities in light of locally relevant evidence.

Martinez GS ，Diaz J ，Hooyberghs H ，Lauwaet D ，De Ridder K ，Linares C ，Carmona R ，Ortiz C ，Kendrovski V ，Aerts R ，Van Nieuwenhuyse A ，Bekker-Nielsen Dunbar M ... -  《-》

Projections of excess mortality related to diurnal temperature range under climate change scenarios: a multi-country modelling study.

Various retrospective studies have reported on the increase of mortality risk due to higher diurnal temperature range (DTR). This study projects the effect of DTR on future mortality across 445 communities in 20 countries and regions. DTR-related mortality risk was estimated on the basis of the historical daily time-series of mortality and weather factors from Jan 1, 1985, to Dec 31, 2015, with data for 445 communities across 20 countries and regions, from the Multi-Country Multi-City Collaborative Research Network. We obtained daily projected temperature series associated with four climate change scenarios, using the four representative concentration pathways (RCPs) described by the Intergovernmental Panel on Climate Change, from the lowest to the highest emission scenarios (RCP 2.6, RCP 4.5, RCP 6.0, and RCP 8.5). Excess deaths attributable to the DTR during the current (1985-2015) and future (2020-99) periods were projected using daily DTR series under the four scenarios. Future excess deaths were calculated on the basis of assumptions that warmer long-term average temperatures affect or do not affect the DTR-related mortality risk. The time-series analyses results showed that DTR was associated with excess mortality. Under the unmitigated climate change scenario (RCP 8.5), the future average DTR is projected to increase in most countries and regions (by -0·4 to 1·6°C), particularly in the USA, south-central Europe, Mexico, and South Africa. The excess deaths currently attributable to DTR were estimated to be 0·2-7·4%. Furthermore, the DTR-related mortality risk increased as the long-term average temperature increased; in the linear mixed model with the assumption of an interactive effect with long-term average temperature, we estimated 0·05% additional DTR mortality risk per 1°C increase in average temperature. Based on the interaction with long-term average temperature, the DTR-related excess deaths are projected to increase in all countries or regions by 1·4-10·3% in 2090-99. This study suggests that globally, DTR-related excess mortality might increase under climate change, and this increasing pattern is likely to vary between countries and regions. Considering climatic changes, our findings could contribute to public health interventions aimed at reducing the impact of DTR on human health. Korea Ministry of Environment.

Lee W ，Kim Y ，Sera F ，Gasparrini A ，Park R ，Michelle Choi H ，Prifti K ，Bell ML ，Abrutzky R ，Guo Y ，Tong S ，de Sousa Zanotti Stagliorio Coelho M ，Nascimento Saldiva PH ，Lavigne E ，Orru H ，Indermitte E ，Jaakkola JJK ，Ryti NRI ，Pascal M ，Goodman P ，Zeka A ，Hashizume M ，Honda Y ，Hurtado Diaz M ，César Cruz J ，Overcenco A ，Nunes B ，Madureira J ，Scovronick N ，Acquaotta F ，Tobias A ，Vicedo-Cabrera AM ，Ragettli MS ，Guo YL ，Chen BY ，Li S ，Armstrong B ，Zanobetti A ，Schwartz J ，Kim H ... -  《The Lancet Planetary Health》

The winter urban heat island: Impacts on cold-related mortality in a highly urbanized European region for present and future climate.

Exposure to heat has a range of potential negative impacts on human health; hot weather may exacerbate cardiovascular and respiratory illness or lead to heat stroke and death. Urban populations are at increased risk due to the Urban Heat Island (UHI) effect (higher urban temperatures compared with rural ones). This has led to extensive investigation of the summertime UHI and its effects, whereas far less research focuses on the wintertime UHI. Exposure to low temperature also leads to a range of illnesses, and in fact, in the UK, annual cold-related mortality outweighs heat-related mortality. It is not clearly understood to what extent the wintertime UHI may protect against cold related mortality. In this study we quantify the UHI intensity in wintertime for a heavily urbanized UK region (West Midlands, including Birmingham) using a regional weather model, and for the first time, use a health impact assessment (HIA) to estimate the associated impact on cold-related mortality. We show that the population-weighted mean winter UHI intensity was +2.3 °C in Birmingham city center, and comparable with that of summer. Our results suggest a potential protective effect of the wintertime UHI, equivalent to 266 cold-related deaths avoided (~15% of total cold-related mortality over ~11 weeks). When including the impacts of climate change, our results suggest that the number of heat-related deaths associated with the summer UHI will increase from 96 (in 2006) to 221 in the 2080s, based on the RCP8.5 emissions pathway. The protective effect of the wintertime UHI is projected to increase only slightly from 266 cold-related deaths avoided in 2009 to 280 avoided in the 2080s. The different effects of the UHI in winter and summer should be considered when assessing interventions in the built environment for reducing summer urban heat, and our results suggest that the future burden of temperature-related mortality associated with the UHI is likely to increase in summer relative to winter.

Macintyre HL ，Heaviside C ，Cai X ，Phalkey R ... -  《-》

Comparative assessment of the effects of climate change on heat- and cold-related mortality in the United Kingdom and Australia.

Vardoulakis S ，Dear K ，Hajat S ，Heaviside C ，Eggen B ，McMichael AJ ... -  《-》