The line that marks the risk of rising heat

The increase in temperatures is an incontestable fact that can be seen from the scientific literature to the analysis of thermal data from historical series: taking into account the Rioja climate, the average has risen more than one degree in half a century and episodes of extreme heat are more recurrent. Being aware of this situation has led to greater concern about the climate crisis and, among other issues, understanding how it affects our health. And the recommendations and alerts may sound repetitive, but they save lives, an approach with which a national plan was developed just twenty years ago that has now released a more detailed map of extreme heat thresholds, above which the temperature rises significantly. impact on health. In La Rioja, three areas are distinguished: Logroño, with a limit of 34.5º, the banks of the Ebro, which establishes it at 34.2º, and the mountains, at 31.9º.

Various investigations and the Ministry of Health itself remember the turning point in 2003. That summer was scorching throughout Europe and triggered a significant increase in diseases and mortality, which claimed nearly 35,000 victims on the continent.

In La Rioja, until recently, it was the hottest on record and still has some events. The average temperature of that June is the highest ever recorded (24.1º) and in August the average maximum temperature was 34.3º, a month of absolute record. 2003 was a year that forced us to rethink the tools, and according to Numerous experts highlighted the lack of adequate prevention strategies and how poorly prepared public health systems were for the consequences of such thermal extremes. A year later, the ‘National Plan for Preventive Actions for the Effects of Excess Temperature on Health’ was born.

The three Rioja indicators

The central approach has not changed, but its focus and development has, progressively incorporating aspects linked to scientific knowledge. The Plan, which was activated last week and will remain in place until September 30, this year includes a more detailed map of the maximum temperature thresholds. Once passed, warnings divided into three risk levels are activated: yellow, orange and red – which was activated on 3 occasions last year. La Rioja will now have different limit temperatures for the two isoclimatic or ‘meteohealth’ zones: the Ribera del Ebro (34.2º) and the mountains (31.9º). In Logroño it is somewhat higher, at 34.5º, and this station, located at the Agoncillo military base, serves as a reference in the national network.

Taking this into account, La Rioja is located in an intermediate position, with a higher temperature limit than practically all the nearby provinces. Only Zaragoza surpasses it with 38º. At the head of the national ranking, those from the south, with a margin of 41.5º in Córdoba, 41º in Badajoz and 40.5º in Seville. The thresholds are noticeably lower in the north, as evidenced by Asturias (26º), Cantabria (26.5º), La Coruña and Guipúzcoa (27.5º).

And how are these risk temperatures established for each area? Starting from two pieces of information: the recorded temperatures and the natural deaths associated with these periods of extreme heat. The threshold marks the point from which mortality increases significantly, also taking into account numerous variables, such as the characteristics of the local homes, the vulnerability of the population, the frequency of heat waves in said territory… The objective is to detail the observation and alerts as much as possible and in the future increase the number of risk variables.

Rising trend

All of these questions gain special relevance each year, and this is confirmed in the numerous studies that analyze not only the effects of high temperatures on our health – exhaustion, cramps, dizziness, heat stroke… – but in other areas such as the social, exacerbating isolation, dependency or marginalization, which also affect the most vulnerable groups. And these episodes are no longer strange. Since 1960, the days of extreme temperatures and heat waves have increased in La Rioja, as revealed by Aemet records.

We must reach the decade of the nineties to find the first year, 1991, in which more than twenty days were recorded with maximums – there were 25 – above the threshold of 34.5º. Until then, the highest number of hot days had been recorded in 1987 and 1990. The upward trend was already unstoppable, remembered with suffocation, already in the new century, the summers of 2019, with 27 days reaching 34.5º and 2009 and 2016 (25). However, the numbers skyrocket when we remember the year 2003, with 35 days above the threshold, and 2022, which with 38 days marks the historical maximum, in the longest and hottest summer of our lives. The previous one, 2023, was a year with fewer extreme dates (23), but some especially remembered such as August 24 for history with its 43.3º.

With summer knocking on the doors, all these data, thresholds, anniversaries and studies focus on the same objective: prevention. Know how to communicate and take small-scale measures and precautions in the face of global warming that is hitting us.