Mediterranean, ground zero for climate change in Europe

“Urgent action is required.” This is the conclusion of the report of the Panel of Experts on Climate Change of the UN (IPCC for its acronym in English). “The increase in heat waves, droughts and floods are already exceeding the tolerance thresholds of plants and animals, causing massive mortalities in species such as trees and corals,” they point out. Changes that can already be seen “such as the disappearance of species,” says Thelma Krug, vice president of the IPCC, and others that are yet to come if climate change is not curbed.

For the first time, the IPCC “destines specific chapters for the regions”, comments Krug, and the Mediterranean “is a hot spot for the advancement of climate change”, warns Jofre Carnicer, member of the Department of Evolutionary Biology, Ecology and Environmental Sciences of the University of Barcelona and author of chapter 13 of the report.

Increasingly, the planet is approaching the limit of 1.5ºC of increase in global temperature set by world powers to limit the effects on Earth. “The average warming is 1.1ºC,” advances Carnicer. “But it is that in the Mediterranean it has already risen 1.5º C”, he adds. “If we do not address mitigation measures, we will reach limits that we will not be able to reverse.”

This red line is a real turning point or “perhaps of no return”, warn the authors of the report. More frequent heat waves, droughts, floods or rising sea levels are some of the risks facing Europe and “the Iberian Peninsula”, adds Marta Rivera-Ferre, a researcher at the Central University of Catalonia and specialized in Mediterranean, especially in food security, gender and sustainable development.

Crossing the 1.5ºC temperature rise, UN experts point out, means “losing 10% of terrestrial ecosystems”. “We are already seeing that more than half of the species are moving towards the poles or to the high areas of the mountains to seek colder areas,” warns Carnicer.

Nothing to do with the drought

In this “very complex” working group, says the IPCC vice president, the IPCC experts are committed to adaptation to “reduce the damage”. However, this one is already done. “Drought in the Mediterranean is going to happen, even if there is a high degree of mitigation,” says Jofre Carnicer. “The drought is going to be there”, he repeats again.

A damage that is already being verified this 2022 in Spain with a significant reduction in rainfall that leaves the reservoirs at 44.3% of their capacity, twenty percentage points less than in the same week of 2021. «For each degree of increase in global temperature, rainfall is reduced by 4%, “warns Carnicer.

Globally, between 800 million and 3 billion people are projected to experience chronic water scarcity due to drought under 2°C warming, and up to about 4 billion under 4°C warming. “This is very serious,” reveals the Catalan researcher.

However, drought and extreme and increasingly frequent heat waves are not the most important risks collected by the IPCC for the Mediterranean. “All these changes will cause, if no action is taken, a rise of between 20 cm and one meter in sea level,” they warn. “This is a significant risk for the Ebro Delta and nearby areas,” adds Jofre.

“The scientific evidence is unequivocal: climate change is a threat to human well-being and the health of the planet,” warns Hans-Otto Pörtner, co-chair of IPCC Working Group II, in the document.

Adaptation is essential to reduce damage, but to be effective, “it must go hand in hand with ambitious reductions in greenhouse gas emissions,” they note.

After its delay in publication due to Covid-19, the United Nations Panel of Experts has been more forceful and tough than ever in its final document. “This report is a serious warning about the consequences of inaction,” denounces Hoesung Lee, chairman of the IPCC. “The cost of inaction is greater than action,” adds Rivera-Ferre.