Ibiza makes record of the year with the least rainfall since 1970

The Club Nàutic Sant Antoni has held a new edition of the 'Xerrades Essencials' series of talks, with the participation of molecular biologist Julia Bauzá and the president of the Sant Antoni Agricultural Cooperative, Toni Tur.

Their conclusions left the large audience speechless, as they presented a climate outlook that delves into the reduction of rainfall, the increase in temperatures and the progressive transformation of the Pitiusan landscape as a result of climate change.

The aim of the talk was to try to answer the question 'Are we experiencing a temporary drought or is it really raining less on Ibiza?’ To do so, Julia Bauzá shared the revealing conclusions she has reached after studying and cross-referencing climate data related to rainfall and temperature on Ibiza over the last 50 years, analyzing projections for the future. 

The discussion began with a presentation by Julia Bauzá, in which she explained her conclusions after analyzing the climate data recorded by the Spanish Meteorological Agency, through the Es Codolar Airport weather station, from 1970 to the present day. The first comparison that the molecular biologist shared was the rainfall in the last two years. In 2022 it rained more than 50 days and more than 400 millimeters (equivalent to liters per square meter), which is close to the average annual rainfall on the island, while in 2023 it has only rained 20 days and less than 300 mm. "It is worth noting that, in all the years for which we have records, 2023 is clearly the year with the least rainfall," she explained.

"We are seeing a progressive trend towards a decrease in rainfall, where not only the average annual rainfall is falling, but also the number of days it rains," added Bauzá, who even quantified the loss of rainfall on the island in the last half century: in the 1970s it rained an average of 50 days and a total of 499 mm per year. In contrast, in the last 10 years it has rained on average 9 days less and 123 mm less per year. "This means that today, we already have about 25% less rainfall and 20% fewer rainy days than in the 1970s," she said.

The molecular biologist also added that the loss of rainfall in spring and summer is worrying. "If rainfall is concentrated in one season and less and less rain falls in the other seasons, the land becomes dry and caked, and then when it rains, the water does not filter well and results in flooding instead of filling underground aquifers," she said.

Data from the airport's weather station can also be used to analyze temperatures, noting that the highs are getting higher and higher. "The hottest months are getting hotter and hotter. In fact, we have broken the monthly maximum temperature record in 11 of the 12 months since the 2000s, and what is more worrying is that, of those 11 months, 8 had the highest temperature record in the last decade," he said.

The reasons for this change in rainfall and temperature are related to climate change, due to the accumulation of greenhouse gasses in the atmosphere, which prevent the atmosphere from cooling. Using samples of Arctic and Antarctic ice, scientists have been able to determine that during the last 800,000 years, before the industrial revolution, the accumulated CO2 in the atmosphere never exceeded 300 parts per million (ppm), while in 2023 it reached 424 ppm.

Julia Bauzá presented three scenarios that are common in this kind of study, to define how the climate on the island of Ibiza could evolve. The most negative scenario suggests that, if we continue at the same rate of CO2 emissions as at present, emissions in 2100 will reach 1200 ppm of CO2, tripling compared to today.

Then there is an intermediate scenario, in which socio-economic policies would be put in place to moderate emissions, peaking in 2080 and decreasing thereafter. In this scenario, emissions would reach about 750 ppm CO2, almost double the current level. There is also a more positive and improbable scenario, which would require urgent action right now, by implementing policies to promote the use of clean energy and ensuring that emissions peak in 2040 and fall thereafter, accumulating some 500 ppm of CO2 in the atmosphere.

In view of these scenarios, and given the evolution of the island's climatology, Julia Bauzá has deduced that, in the best of the three cases, rainfall will continue to decrease, and could fall by between 10% and 30% by 2100. In the worst-case scenario, rainfall could fall by between 25% and 40%.

In the best-case scenario, maximum temperatures would rise by 3-4 degrees Celsius by 2100, while in the worst-case scenario they would rise by 6-7 degrees Celsius, reaching peaks of 50 degrees Celsius in August.

All these changes would have consequences beyond drought and heat waves, as they would also result in an increase in fires, which would also become more virulent, as well as in a greater number of natural disasters, and would have very harmful effects on people's health.