July 28, 2021

The effects of global warming trigger the risk of fires in the Mediterranean | Science

The effects of global warming trigger the risk of fires in the Mediterranean | Science


The brutal waves of fires registered in the last two years in Portugal, Spain and Greece have revealed the vulnerability to fire of Mediterranean Europe. And there are more and more signs that the situation will get worse if the planet keeps heating up. A study published on Tuesday in Nature certifies that the areas burned in summer in the region will increase considerably even in the best of the scenarios foreseen by the Paris Agreement against climate change (an average increase in global temperature of 1.5 degrees C above pre-industrial levels). The impact of the fires would grow progressively depending on whether the global average temperature increased two or three degrees, the authors say. Although they point out that possible variables that are difficult to predict could force them to revise these projections, they and other experts agree that, in a warmer Earth, the devastating potential of fires will be greater.

One of the most important factors in assessing the vulnerability of a region to fires is the degree of drought, explains Marco Turco, lead author of the new study. "The more there is drought, the more the likelihood of fires increases. And droughts in the Mediterranean area have increased in recent years, "he says. The scenarios related to climate change do not foresee a different trend in the future. The global warming produced by the human being will cause, among other effects, new heat waves and negative anomalies in rainfall rates in many areas of the planet, according to different studies.

The threats of climate change led in 2015 to more than 50 countries to sign an agreement in Paris committing themselves to reduce the average increase in global temperature, says Turco. The international agreement imposes as a minimum objective that the warming stay "well below the two degrees with respect to the pre-industrial levels", with the final purpose of achieving to reduce this warming to 1.5 degrees. The link between drought and the risk of fires and the parameters set in the Paris Agreement were the premises on which this researcher from the University of Barcelona and his team relied to explore how such factors could influence the future predisposition to Flames of the Mediterranean area.

Scenarios

The study presents three scenarios of global warming: one with an average temperature increase of 1.5 degrees, one with an increase of two degrees and one with an increase of three. Turkish specifies that he was not interested in what moment one of these scenarios could occur, but what would happen at the moment in which it occurs. In the statistical models used to construct the forecasts, the authors have also taken into account multiple variables that increase the uncertainty about how these projections could evolve. According to they affirm, an example is the possibility that more drought limits the growth of the vegetation and, therefore, the combustible material. "We have tried to quantify not only the impact of climate on fires, but also the possible changes in the relationship between climate and fires," explains Turco. The available data have allowed the development of regional projections for an area that includes the territories of Portugal, Spain, southern France, Italy and Greece.

Effects of the fire in Llutxent last August.
Effects of the fire in Llutxent last August. efe

You look at the matter where you look, the bottom line does not change, says Turkish. One of the main results of the research is that "although global warming is limited to 1.5 degrees, in Mediterranean Europe an increase in fires is expected," he says. He and the other authors calculate that, should this scenario occur, the area burned in summer (the best index for evaluating the impact of flames in a territory, according to Turco) would increase by around 40% compared to the current average. If global warming could not be maintained below two degrees, the impact could be even higher: with a rise of three degrees, one would have to wait until 100% more total burned area, concludes the study.

A change of model

To José Manuel Moreno, from the University of Castilla La Mancha, these results do not surprise you. "Climate change will affect the growth conditions of the vegetation and its state, enough so that fires can be altered," he says. "The decrease in precipitation that is expected to occur, along with the increase in temperatures that is also expected, are the main elements of its potential increase," he adds. The characteristics of a country like Spain generate a particular vulnerability. "Spain occupies an area in which we do not have much rain, but enough so that the vegetation is abundant and can burn when the conditions are favorable", considers this professor.

The expert assures that, in the last three decades, the number of fires in countries such as Spain, France and Italy has dropped considerably despite favorable conditions for fires have increased. This is a consequence, in his opinion, of the large investments in the issue of effectiveness in the management of emergencies. Variables such as man's ability to intervene can therefore influence the percentage of fires, he explains. But he believes that multiple alarms about the negative impact of warming can not be ignored. "If the summer conditions get worse, the fires will increase. They can do so to a greater or lesser extent, depending on the effort we make to stop them. But it is certain that more effort will have to be made to obtain the same result ", he assures.

Fire in Valencia last summer.
Fire in Valencia last summer. ap

Raúl Quílez, doctor in forest fires and coordinator of extinctions of fires in Valencia, considers that taking into account some variables, such as the amount of rainfall in spring, is important to be able to develop projections of the most precise risks. In his opinion, it is necessary to study the specific characteristics of each territory and take management measures adjusted to each environment. "In a scenario of non-management or timely management, such as we have right now, fuels will grow and will occupy many agricultural areas," he maintains. "In that scenario there can be much more severe and intense fires," he adds.

For all these reasons, Turco believes that it is essential to focus efforts on preventive actions of danger. "Currently, apart from some exceptions, the greatest effort is devoted to suppressing fires. I think we should allocate more energy and investment to the management before the disasters happen, not just later, "he says. Moreno adds that it could be a good strategy in this regard to revise downward the goal of global warming reduction foreseen in the Paris Agreement. "Taking it to 1.5 degrees instead of two degrees can be a major relief in the danger of fire," he says.

.



Source link