This summer has been the third with the highest mortality attributable to excessive heat, with 2,155 deaths, after the heat wave of 2003 and the summer of 2022, which accumulated 3,012 deaths. This is one of the conclusions drawn from a new digital tool, a web application still under development, created by scientists from the Institute of Environmental Diagnosis and Water Studies (Idaea-CSIC) in Barcelona, the University of Valencia and the Foundation for Climate Research.

The web application called Attributable Mortality by Heat in Spain (MACE) is based on data from the Daily Mortality Monitoring System (MOMO) of the Carlos III Health Institute and the temperatures recorded by the State Meteorological Agency (Aemet) to calculate the mortality attributable to moderate heat, extreme heat and excessive heat in the period of the year from June to August.

It is updated daily but, like the MOMO and Aemet data, it is two days late. Its authors are working so that, in addition to national data, the tool provides information on differences by province and vulnerable population groups (age and gender). They also plan to extend data collection from May to October for the next version of the app, scheduled for 2024.

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Bless you.

Heat seriously harms your occupational health

  • Written by: CRISTINA G. LUCIO Madrid
  • Written by: INFOGRAPHIC: MAITE VAQUERO

Heat seriously harms your occupational health

Bless you.

Asturias at 26º can be just as dangerous as Cordoba at 41.5º. From what temperature does the risk skyrocket in each Autonomous Community?

  • Written by: ANA SOUSA
  • Written by: ESTRELLA LÓPEZ
  • Written by: ELSA MARTÍN (GRAPHICS)

Asturias at 26º can be just as dangerous as Cordoba at 41.5º. From what temperature does the risk skyrocket in each Autonomous Community?

Since January, the MoMo has counted 329,462 deaths, 6,834 attributable to temperature, according to the latest report published. Thus, Galicia with 1,704 is the most affected community, followed by Andalusia with 1,276 and Castilla y León with 683.

The INE is slow to purge cases

Aurelio Tobías, a researcher at Idaea and author of the work, explains to this newspaper that the Aemet and the Ministry of Health give notice of the arrival of a heat wave but do not report what the potential impact is on health or that of isolated days of extreme heat. In his opinion, the MOMO is a "very good system for monitoring daily mortality from all causes, which is something that involves a very large effort", but as far as heat mortality is concerned, it could be improved "from environmental epidemiology". He also recalls that it takes about two years for the National Institute of Statistics (INE) to "purge the causes of mortality and age groups", so that in real time what is known is the trend.

It also clarifies that, for now, MACE, by offering a national picture of what is happening and not discriminating by geographical areas, may be offering an overestimated mortality. In other words, a heat wave causing excess mortality does not affect the entire country at the same time and equally, contrary to what the application reflects.

Tobias also points out that excess mortality due to heat, something that occurs more in older people and people with cardiovascular and respiratory pathologies, is usually related to deaths from heat stroke, which would be much fewer: 285 cases registered in Spain between 1990 and 2016, according to an article published this month in Epidemiology.

The new application, according to the researcher, has been well received by scientists in his field, who consider it necessary in a context of climate change and progressive increase in temperatures, and also very useful because of the possibility it offers of being able to take historical evolution into account.

How is mortality calculated in the new app?

In the application, moderate heat-attributable mortality "is calculated as the sum of the contributions of the summer days of 2023 with temperatures between the minimum mortality temperature as a counterfactual reference and the 95th percentile of the temperature distribution between June and September over the past ten years."

Mortality attributable to extreme heat, "as the sum of the contributions of days above the 95th percentile." And mortality attributable to excessive heat, which is considered as a part of extreme heat, "as the sum of the contributions of days above the 95th percentile as a counterfactual reference."

The definition of the extreme heat threshold as the 95th percentile of the temperature distribution between June and September over the last ten years is based "on the similarity with the definition of the reference thresholds for the impact on health of high temperatures in the National Plan of Preventive Actions for the Effects of Excess Temperatures of the Ministry of Health".

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