Heatwaves have claimed over 1,800 lives in Spain so far this summer

This summer’s extreme temperatures in Spain, have resulted in over 1,800 deaths, a shocking reminder of the dangers of the heat. Since June 1st, the Daily Mortality Monitoring System (MoMo) of the Carlos III Health Institute has recorded 95,904 deaths. Of these, 1,834 have been directly linked to the scorching heat.

The data shows a peak on August 12th with 79 deaths, however, the latest figures from August 22nd indicate 68 heat-related deaths, though these numbers are continually updated.

“The impact of heat isn’t merely heat stroke, which is the least of concerns. The heat itself is a stress for the body,” says Dominic Roye, Head of Data Science at the Climate Research Foundation (FIC). He, along with Aurelio Tobias from the Centre Superior of Scientific Investigations (CSIC) and Carmen Iñiguez from the University of Valencia, recently launched the Summer Heat Attributable Mortality in Spain (MACE) application.

According to Roye, MACE offers a ‘far more modern’ statistical estimate than MoMo, which still employs a 1990s methodology. MACE’s data suggests that from June 1st to August 22^nd last year, there were 8,821 heat-attributable deaths. However, it doesn’t account for geographical differences, gender, and age groups, potentially overlooking many more fatalities.

MACE utilises MoMo’s death data and average temperatures provided by AEMET. Their findings reveal that 3,034 of these deaths occurred on days of extreme heat. August saw 10 such days, resulting in 1,883 deaths, while July had five days leading to 1,151 deaths, and June had none.

Roye explains that the mortality rate spikes when the average temperature reaches 26.9°C. This summer’s average has been 24.5°C, with August at 26.2°C and July at 25.3°C. Although this summer has been extreme, it hasn’t been as severe as 2022, which witnessed 28 days of extreme heat and 8,815 related deaths.

Official data from the INE indicates that mortality surged by 20% between May and August 2022, with heat stroke and dehydration deaths doubling compared to three years prior. 

Heat strokes account for only 2 to 3% of heat-related deaths. The primary concern is the exacerbation of existing health issues, particularly cardiovascular and respiratory ailments. A 2021 study co-authored by Roye highlighted the dangers of hot nights in southern Europe. It found that daily mortality is linked to nighttime temperatures exceeding 20°C, irrespective of daytime heat. Climate change is increasing both maximum and minimum temperatures.

Poor sleep due to extreme heat also poses health risks. Ana Teijeira, a neurophysiologist from the Spanish Sleep Society (SES), states that optimal sleep occurs between 18 and 21°C. However, temperatures above 24°C make it nearly impossible.

This recent heatwave saw nights nearing 30°C in parts of Spain. The consequences range from fatigue and irritability to long-term issues like hormonal changes and increased risk of heart attacks.

To combat the heat, Teijeira suggests maintaining a regular sleep schedule, wearing light clothing, ensuring a dark environment, and aiming for room temperatures between 18 and 21°C. If these conditions aren’t achievable, a warm shower, not too cold, can help lower the body’s temperature, signalling it’s time to rest.