This article is republished from The Conversation under a Creative Commons license.
Three people sit in the shade to escape the heat in Barcelona. Photo by Laura Guerrero courtesy of Ajuntament de Barcelona (CC BY-NC-ND 4.0).
The first heatwave of the summer hit Spain, Portugal, France, Italy and Germany early in the year, breaking June temperature records in many areas. It was Western Europe’s warmest June since records began, and Spain’s warmest since it began recording temperature anomalies in 1961.
Temperatures soared past 40ºC in the last week of the month in large parts of the southern half of peninsular Spain, mainly in Andalusia and Extremadura, as well as in other more northerly places like Ourense, in Galicia, and Girona in Catalonia. The most extreme numbers recorded in the Iberian states were 46.6ºC in Mora, about 100 km east of Lisbon, and 45.8ºC in El Granado, in the Andalusian province of Huelva.
Nights were unbearable, making a good night’s rest all but impossible in Mediterranean city centers and in the southern half of Spain and Portugal. Barcelona was especially bad: in the central Raval area, every night during the last ten days of June was torrid, meaning minimum temperatures went no lower than 25ºC. This continued into the first days of July.
The waters of the Mediterranean Sea are also abnormally warm for the time of year, equivalent to the August records of the last two summers. Water holds onto heat, meaning this marine heatwave is almost guaranteed to last all summer and well into autumn. At least in sea waters and coastal or island areas, above-average temperatures are now here to stay.
A Warming Continent
Beyond the Iberian Peninsula, June temperature records were broken in northern Germany, various parts of France and in the Norwegian Arctic. A strong anticyclone at high altitude carrying air from the Sahara caused this early heat wave.
The anticyclone formed the cover of a huge dome of warm air that covered the Iberian Peninsula and much of western Europe. This persistent anticyclone also occurred on the days with the highest potential sunshine, including the longest day of the year, when the sun reaches its highest point above the horizon.
At this stage, it is difficult to know whether there will be more heat waves this summer. Seasonal forecasts for the July-August-September quarter indicate that the probability of above-normal average temperatures is high, over 70% in Spain and in much of Europe. In recent summers, the occurrence of several heat waves in southern Europe has become the norm.
Health Impacts
Excessive heat, both during the day and night, has a negative impact on human health. Humans have an almost constant internal temperature, between 36.5 and 37 ºC.
When the outside temperature is close to or higher than this, cutaneous vasodilatation—increasing the blood circulation in our skin to release heat—is of no use to us. If the environment is at a higher temperature than our bodies, the air will then transmit heat to us. This leaves us with one final mechanism to keep our internal temperature under control: sweating.
No other animal has such a high number of sweat glands and sweating rate as humans. Sweat, consisting of water and mineral salts, evaporates from the skin and, like all evaporation, causes cooling. Naturally, we have to replenish the lost fluid by drinking abundantly, otherwise we become dehydrated.
Foods such as gazpacho and salads provide us with water and salts. Water-rich fruits like melon are also recommendable, and often very appealing, in warm weather.
Beyond dehydration, heatstroke is a very dangerous effect of excessive heat. When a person’s body temperature rises above 40ºC, they may faint and need urgent medical attention. If they fall into a coma, the damage can be irreversible.
During this latest heatwave, there were an estimated 2,300 deaths attributed to heat across Europe. Many other deaths were also indirectly attributed to high temperatures in several countries due to the aggravation of chronic conditions.
This is a public health problem, in particular for the elderly and chronically ill, who are very vulnerable to heat, especially if they are in conditions of energy poverty. Without measures like air conditioning, people cannot rest well at night, they become weaker, and their morbidity increases. This means higher rates of hospital admission and overall mortality.
Although the countries of southern Europe are the most frequently and intensely exposed to very high temperatures, adaptation to extreme heat must also be a priority in the central and northern countries of the continent, which are less accustomed to heatwaves. Most homes and public spaces in these countries do not have air conditioning, and people’s habits and lifestyles are not currently suited to withstanding abnormally high temperatures in these areas.
Javier Martín Vide, Catedrático de Geografía Física, Universitat de Barcelona
This article is republished from The Conversation under a Creative Commons license. Read the original article.
