Explaining a chain reaction is a very simple exercise. Just picture a long row of dominoes falling one after another. Or think about the ancient Chinese proverb, which states that “The slight flutter of a butterfly can be felt on the other side of the world.”

These wise and intuitive approaches are however often ignored in favor of an overwhelming and irresponsible presentism. The commonly known “butterfly effect” is widely assumed, but when it takes the form of various problems, attention turns elsewhere. This inattention is cultivated by multiple factors, but undoubtedly one of them is the incorrect perception of the magnitude of our actions.

In the case of climate change, when explaining a long concatenation of causes and effects, it is important to cover every single fact. However, a quick search through the news shows that regularly give updates on current environmental problems seems to disregard the facts for the whole picture. In this sense, a serious sentence like “Snow levels in the Pyrenees decrease by x centimeters this year,” should be completed as: “Snow levels in the Pyrenees decrease x centimeters this year, compromising the balance of its delicate ecosystem and directly threatening the local people, who lose crops and working hours in the tourist sector.”

The intensive research surrounding the Pyrenees speaks for the uniqueness of the region. Each of the “dominoes” is very well documented, thanks to the work of the Pyrenean Observatory of Climate Change (OPCC), whose reports ground part of this article.  The domino effect of which these pieces are part is not very encouraging: multiple localities, which are crossed by the mountain range, are jointly suffering the effects of an unstoppable and dangerous increase in the average temperature.

In the last sixty years, the average temperature in the Pyrenees has increased abnormally, by about 0.24 ºC per decade. The speed at which the temperature is rising is outrageous, even compared to past warming periods. The Pyrenean climate is the first victim of these extra degrees. Abrupt meteorological changes are affecting the mountain range. Despite the fact that the region still goes periods of more intense rainfall and snowfall, it is estimated that its snow cover could be reduced by half in the 30 next years, and it would melt from the ground one month earlier.

Effects on fauna and flora

In this context of meteorological turbulence and accelerated warming, native life bears part of the brunt. Biodiversity is suffering serious losses and some of the species are being depleted because they are unable to survive the wide range of hostile conditions that affect the mountain range.

In one of its latest reports, the OPCC indicates that the most sensitive animals, such as birds and amphibians, are becoming less abundant. In some cases, species are also suffering pysical alterations.

The most dramatic case is that of amphibians, like newts and frogs, which are very susceptible atmospheric variations. Amphibians are specifically sensitive to humidity, which is decreasing in the Pyrenees due to the scarcity of the Pyrenean boxwood, a native plant to the region.

The case of the Pyrenean frog is deeply concerning. This small amphibian, which is in danger of extinction, is prone to contracting ranavirus. An altered habitat, contaminated by human activity, favors the appearance of this virus among frogs. Recently, the Zaragoza aquarium announced the successful captive breeding of 250 frogs, of which 220 will be released. However, if conditions are still not favorable, they will suffer the same fate.

Flora is also suffering from the major changes in its habitat. As temperatures increase, animals that can move occupy higher altitudes to preserve their living conditions, but plants cannot follow the same technique. This throws the ecosystem out of balance.

In addition, plants are severely affected by the scarcity of snow, one of the first pieces of this domino effect. The lack of snow prevents plants from being properly insulated in winter, thus increasing the chances of their perishing. Another major problem for the flora is the presence of pests, which are attracted by the heat and usually more resilient than native species.

The boxwood of the Pyrenees or buxus sempervirens is a very rich and useful plant for life in the area, since it generates high levels of humidity. Humidity allows a large part of the flora of the Pyrenees to develop under the right conditions. Given the high presence and relevance of boxwood in the area, any condition that negatively affects this particular humidifier becomes a great threat to the ecosystem of the mountain range. Present in almost 80 % of the Pyrenees, the buxus sempervirens suffers the attacks of the Cydalida perspectalis: an invasive moth that feeds on boxwood.

Economic effects

All these problems may seem far away when talking about the Pyrenean frog or boxwood, but they are not the only victims of the effects of climate change in the Pyrenees. Climate change also has a significant socio-economic impact in the region.

Crops are less productive and susceptible to pests. The snow season, which attracts so much tourism and generates so many jobs, starts later and lasts less. Fluvial scarcity leads to less hydroelectric power, and the increasing extreme weather events –like foods or heat waves- can obviously have serious repercussions on the course of human life and infrastructure in Pyrenean localities.

How can the situation in the Pyrenees be mitigated? Scientific research is key to detect, treat and communicate the delicate situation of the border mountain range.